Some autofocus fan(atic)s try to dismiss the various technical tests and problems cited in these pages. But it is harder to ignore many postings by autofocus camera owners and users who cite problems they have experienced. These postings discuss issues you aren't likely to see in the ads for autofocus cameras or lenses, but may want to know about (as I did!).

From Nikon Digest:
Date: Sat, 31 Oct 1998
From: George MacArthur Henke images_garden@ibm.net
Subject: Dumbing Down of Nikon lenses.

DOF

What on earth keeps Nikon from putting DOF scales on their zoom lenses?

I think they save $7 per lens. Big deal. I loved the colored lines on the old MF lenses.
- --------------------------------------------------------------------

This is one of the most irksome things which Nikon has done with its recent lenses. They assume that we are all just using our auto-focus like good little robots.

Try to explain hyperfocal distance to students whose lenses have no DOF markings. It is another reason to prefer MF lenses unless you are visually handicapped or photographing moving subjects, they have the DOF markings.

George

From: Hutto@IBM.Net (Brent Hutto)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Buying new camera AF or manual????
Date: 18 Oct 1998

"S. Gareth Ingram" sgingram@venus.uwaterloo.ca wrote:

 Modern AF cameras do not in general have the focussing aids in the
 viewfinder that you get in the old MF cameras. I am thinking mostly of
 split prisms and microprisms. Modern AF cameras have as little clutter
 in the viewfinder as possible and are optimised for brightnes at the
 expense of what is best for manual focussing. If you are going to stick
 with MF lenses you will be better sticking to an MF camera body.

I'm a beginner with a ZX-M and this is something I've been wondering about. If I use the split-image/microprism area to focus, often the focus is not "perfect". Maybe "good enough" but not quite right. I've switched to only using the matte area of the screen and get "perfect" focus surprisingly often (like 80-90% of the time versus maybe half the time with the "focusing aids"). For me, the "focusing aids" just waste the center of the viewfinder and I have to point the camera to one side if I want to focus a centrally-located object.

Is it just me? Is it just my ZX-M? Or does everyone get better focus using the matte screen (which takes longer) and the focusing aids are just intended as time-savers?

From: qdmphan@aol.com (QDMPHAN)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Buying new camera AF or manual????
Date: 18 Oct 1998

I actually changed the screen of my Nikon FA to a matte screen instead of the standard split screen because i could actually focus much faster with out the split screen. I've always gotten sharp pictures using the matte screen .

Q

From: w.j.markerink@a1.nl (Willem-Jan Markerink)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: What do Nikon users think of Canon EOS3?
Date: Sun, 25 Oct 98

Someone on a mailing list said Canon states that it has a semi-permeable
mirror, resulting in some light loss in the viewfinder. Supposedly it
was necessary to accomodate the 45 AF points. If this is true, it's
going to be another strike against it.

No EOS (moving) mirror is 100% reflective, and the same goes for every AF camera. You simply need light behind the mirror, for AF and some light meter cells to operated. This is mostly a 66/33 reflecting/transmitting ratio, exactly the opposite from the EOS RT and 1n RS (33/66). Note that this difference causes a 1 stop difference in the viewfinder (and not a 1.5 stop difference that a 100% reflective moving mirror would have resulted in)....and in case of the 1n RS this 1 stop is compensated by a very bright viewfinder screen (which you can also use in the normal 1n, but it makes manual focus more difficult).

--
Bye,

Willem-Jan Markerink

From Nikon Digest:
Date: Fri, 30 Oct 1998
From: "Roland Vink" roland.vink@ait.ac.nz
Subject: DOF scales on their zoom lenses

What on earth keeps Nikon from putting DOF scales on their zoom lenses?

As far as I know, the only zooms with DOF scales are one-touch manual lenses, such as the AIS 35-105/3.5-4.5 and 80-200/4. The DOF marks on these lenses are beautifully curved colored lines on the barrel below the focusing/zoom ring.

Why do the lines curve? For a given focus distance, the DOF is wider at shorter focal lengths, and narrower at the long end. As you push or pull the zoom ring, you will see how the DOF changes as the focal length changes. The DOF markings are easy to read because they are directly under the focusing scale.

Now, if you take a look at the design of AF zooms, you see that this type of DOF marking is not practical. Only a few AF zooms are of the push-pull type, so it would be possible to put the curved DOF lines on the barrel. However, the distance scale is usually at the top of the lens, too far away to be able to read it against a DOF scale on the barrel.

Most AF lenses are two-touch style, so the curved DOF lines do not make sense. It would be possible to print DOF markings below the distance scale, but these markings would be true for only one focal length. I think such a scale would be more c onfusing than helpful. If you want DOF scales on your zooms, I guess you could tape a couple of scales to the lens for the focal lengths you use most often. Not a perfect solution, but it will at least give you some indication of the DOF. Personally, I usually stick to primes which have very good scales.

Roland.

From Nikon Digest:
Date: Fri, 30 Oct 1998
From: Dmin@aol.com
Subject: Re: Autofocus helps composition?

Terry Graham wrote:

My theory on it is that autofocus allows the photographer to concentrate on composition and not worry about focussing. Thus necessitating using only the zoom ring and not worrying about focussing. I find when I use my 2 AF zooms (both 2 touch) on either my F90X or F601 bodies, I keep my hand only on the zoom ring.

Frankly I have a problem with this. The confines of Autofocus must be taken into consideration in composition. For instance: if the AF sensor isn't where you want it compositionally then you must adjust your composition if you want to maintain AF. The point of focus is an integral part of composition. AF for portraits is useless as you need to focus on the eyes and with the limited depth of field of most portrait lenses you can't have the AF system focus on the nose and maintain the DOF that you need and still the eyes won't be critically sharp. I find the AF system of the F5 to be technically excellent and for sports work it is just about perfect but for my general assignment work it is still way too limiting in how I must compose. So I continue to manually focus. My compositions rarely put the point of critical focus where any AF sensor is or would be located. I have been telling people for years that "Automatic" does not mean anything other than "Being done by something other than you." My automatic focusing system could be a computer or my cousin Larry. Neither will make my focusing perfect. Using a camera is easy. There are only 3 controls, aperture, shutter speed and focus. The integration of those 3 are what photography is all about.

If you aren't used to thinking about how to adjust the focus ring, then you are thinking about how to keep the camera autofocusing. Learn to do it yourself.

Jonathan Castner
Photojournalist
Denver

From: grumpysworld@my-dejanews.com
Newsgroups: rec.photo.equipment.35mm
Subject: AF - will they EVER learn?
Date: Sun, 01 Nov 1998

How long will it be before a manufacturer offers an AF body that is actually worth owning? Specifically, when will they let us take AF photos without the subject being in the dead-center of the damned frame?

I had hopes for the EOS3, what with 45 AF points, you'd think they could have put at least SOME of them where we might want them to be, but NO. They had to jam ALL of them into a tiny little ellipse right smack dab in the center of the frame.

Now before Mr. Smartypants tells me 'that's what the AF lock button is for', just keep in mind that I actually like my pictures to be sharp. That's why I use a tripod. Using AF lock and a tripod is about as convenient as scratching your left ear with your right toe. Think about it. You have to center the subject, then AF (and lock), then recompose, then lock everything down tight, then take the picture. And what if the subject is moving? I guess we're just perpetually screwed.

Cheers:
Grumpy
grumpy@actionphotographic.com
http://www.actionphotographic.com/grumpysworld/guide/sale.htm

Date: Mon, 02 Nov 1998
From: Lars lars_arend@yahoo.com
Subject: Re: Why Nikon MF lenses are more expensive than AF?

Borcsiczky Zsolt wrote:

 Are Nikon MF lenses substantially better optically or mechanically that
 they are almost always cost more than their auto-focus counterparts? Or
 is it some demand/supply thing only?
 I'm about to buy some primes beside my zooms for my F90x and I'm
 considering about buying MF lenses as I don't really use the camera's AF
 system. But I like the 3D metering of the camera what I should also lose
 with an MF lens.
 So the question is: does it worth to buy an MF lens, or buy the AF lens
 and set the AF turned off?

 --zsolt

I used both MF and AF lenses. The MF lenses are very much better mechanically, but not necessarily optically. There are some very good MF lenses that you can't get (105/2.5, 135/2.8, 1.4/35, 4.0/80-200) as AF versions. The alternatives (AF 28/1.4, 2.0/135, 2.0/105) are ridiculously expensive. The AF 1.8/85 is optically better and cheaper than the MF 2.0/85.

Good mechanical quality is expensive. Combined with slowing demand for MF lenses this causes the very significant difference in price.

I found using AF lenses in MF mode on Nikon terrible. AF is extremely loud, too. The aperture of MF lenses is not shown in the viewfinder of a Nikon AF camera (except F4/F5), and several nice features also only work with F.

For me this was a reason to switch to Contax. Many Zeiss lenses are not much more expensive than their Nikon counterparts (some - the 2.8/28, 2.8/35, 1.4/50, 1.4/85, 2.8/135 are even cheaper), but better optically and at least on par mechanically.

Lars

From: "Michael Covington" mc@ai.uga.edu
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Why Nikon MF lenses are more expensive than AF?
Date: Mon, 2 Nov 1998

One might add that some AF-Nikkors are mechanically rugged (e.g., 50/1.8) while others seem flimsy and easily disturbed by movement (e.g., 35-80/4-5.6).

--
Michael A. Covington - Artificial Intelligence Center - University of Georgia
http://www.ai.uga.edu/~mc http://www.mindspring.com/~covingtonR

From: mathison mathison@ix.netcom.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF - will they EVER learn?
Date: Tue, 03 Nov 1998

...

 This all sounds vaguely reminiscent of the 19th century buggywhip makers/users
 when them new fangled autymobiles came along.  Think of all that  fertilizer
 they had to give up.

 And how many people driving around in those automobiles polluting the
 planet really need to use it???

Good point but once cars caught on the infrastructure that made horses viable disappeared.

As for AF the major problem I have is that wide open is is not nearly as accurate or consistant as focussing by hand and with all the electronics in a camera today what are the chances that in 10 or 15 years there will be parts around to keep these expensive gadgets working. And planned obsolesence really annoys me. That being said if I was a sports photographer I would have all AF bodies.

--
Bob Mathison - Curator,
Museum of Woodworking Tools. http://www.antiquetools.com

From: mathison@ix.netcom.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF - will they EVER learn?
Date: Tue, 03 Nov 1998

I typically shoot wide open in low light. I want critical focus on the eyeball of the person I am shooting which won't be in the center of the shot. AF isn't smart enough to know that I want to focus on an eyeball not an eyelash or nose and at 90mm and f2 with dof at about 3/8" this is important. The second thing is that many times I want to move the focus off a specific object into a region, say off the necklace which I can clearly see to two inches forward so the folds of a dress come into focus but are very dark so by eyeball I can't exactly see what I am doing. In which case I would focus on the necklace and twist the dial a little further. since I do this intuitivly and automaically it is considerably faster than turning AF on and off and my lenses are designed for precise hand adjustment.

Another key skill is guesstimating focus and presetting the camera as I am raising the camera so that by the time the camera hits my eye I have taken one picture and I am ready for the second. This is considerably faster than any autofocus operation but it takes a lot of practice.

I have nothing against AF I just don't see the point of it doing the work I do.

j

From: rpn1@cornell.edu (Neuman-Ruether)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF - will they EVER learn?
Date: Tue, 03 Nov 1998

...
Hmmm, try a Nikon F/F2/F3 with a "B" or "E" screen... These are quite easy to use for focus over most of the frame area (heck, even with an f3.5 16mm fisheye!) so long as your eye will sharply focus at the approx. 3.5' effective viewing-screen distance. One problem with AF cameras is that the viewing systems have become less sharp than those found in older cameras, making MF harder. Even late MF bodies, due to attempts to keep the VF system compact and bright, have compromised frame-edge sharpness and focus accuracy. The difference often isn't obvious, since most older MF VF's have their centers cluttered with those (for me...) useless "focus aids" - which (for me...) occupy prime screen territory for quick/easy MF, using a matte surface...

David Ruether
ruether@fcinet.com
rpn1@cornell.edu
http://www.fcinet.com/ruether

From: kgelner.bork@bork.bigfoot.bork.com (Kendall Helmstetter Gelner)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF - will they EVER learn?
Date: Tue, 03 Nov 1998

I find AF useful in really low light situations (like night shots) where I might not be able to quite make out when it's really focused. I can have it focus, set it to manual focus, then take a long exposure and have it be well focused.

Apart from that, I've had a few shots that I really liked that I wouldn't have been able to get if I spent any time at all focusing manually - AF is great for spur of the moment shots.

From: Russell Williams williams@adobe.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF - will they EVER learn?
Date: Tue, 03 Nov 1998

grumpysworld@my-dejanews.com wrote:

 How long will it be before a manufacturer offers an AF body that is  actually
 worth owning? Specifically, when will they let us take AF photos  without the
 subject being in the dead-center of the damned frame?

Um, as opposed to what? Every MF 35mm camera I ever owned could only be reasonably focused with a focus aid like a split image -- in the dead center. How many people ever owned an MF body with a solid ground glass screen suitable for focusing anywhere? How many people are even capable of focusing on ground glass at that size? Ground glass is pretty dim to begin with, and if you've got an f/3.5 or slower lens in less than ideal light, you're pretty much back to the focusing aid or the AF points. Even 3-5 point AF sensors typically cover a wider area than a split image aid.

I find that a more common problem is that when working on a tripod I often don't want to focus on any obvious subject -- I want to set a hyperfocal distance. So I either AF and read the lens barrel or estimate the near distance, pull out my reference card, switch to manual focus, and set the lens. Canon has an answer to this with their depth mode, I realize.

The real answer is that if lots of people really *wanted* AF points out to the edges of the frame, we'd have them. The conclusion I draw when I want a camera feature that would be easy to build but doesn't appear on any camera anywhere is that the most likely explanation is that most other people don't really want it, or that it's been tested and found not to work well.

The converse isn't true -- I've seen plenty of camera features that were obviously put in because somebody thought it was cool or obvious but in reality almost nobody wants it (power zoom comes to mind), or features that people *think* they want but have no real utility.

Russell Williams
not speaking for Adobe Systems

rec.photo.equipment.35mm
From: "Paul" paulus@ieee.org
[1] Re: Nikon AF/MF price difference?
Date: Thu Nov 05 1998

Although the optical construction is often the same between AF and MF lens types (although not always), I think the AFs tend to be of more plastic construction that MF types. I guess this reduces weight of moving parts which helps autofocus. MFs are more metal contruction which probably makes them

Russell Williams
not speaking for Adobe Systems

rec.photo.equipment.35mm
From: "Paul" paulus@ieee.org
[1] Re: Nikon AF/MF price difference?
Date: Thu Nov 05 1998

Although the optical construction is often the same between AF and MF lens types (although not always), I think the AFs tend to be of more plastic construction that MF types. I guess this reduces weight of moving parts which helps autofocus. MFs are more metal contruction which probably makes them tougher - and more expensive. The MF market is likely to be more pros who are less cost sensitive and often have higher demands on durability.

 Why is there such a big difference in the price of Nikon's autofocus
 lenses as opposed to their manual focus lenses? Is it glass quality?
 Plastic instead of metal?

I think in most cases it's just quantity! They sell much more AF lenses
so they are cheaper.

And those who realy want the MF lenses have to pay. :-(


Manfred Grebler         

From Nikon Digest:
Date: Thu, 5 Nov 1998
From: Richard Mendales rmendale@law.miami.edu
Subject: Re: Lens question

Calvin,

The 80-200 F4.5 AI is quite a different lens from the 80-200 F4.5-5.6 AF. The AI lens is the original Nikon 80-200 zoom; it was made in both pre-AI and AI mounts, and was replaced by the 80-200 F4 AI/AIS lens. It is a superb lens, both optically and mechanically; many users consider it sharper than its F4 successor, and it is significantly less heavy and bulky, without much of a tradeoff in speed or quality of construction (like most AI lenses, it's built like a tank). For users who don't require AF lenses, it even has some advantages over the 80-200 F2.8 AF-D series, since it is much lighter, takes smaller filters, and performs better close up and with extension rings. It lacks ED glass, however, and the slow speed can be a problem.

The new 80-200 F4.5-5.6 is a different lens entirely. It is a consumer grade lens, which, unlike the older lens, has a variable aperture and is largely plastic in construction. It does have the advantage of being still lighter and more compact, but there is a major tradeoff in build quality. Optically, however, I would be inclined to rate it as better than average.

Hope this helps!

Richard Mendales
University of Miami

rec.photo.equipment.35mm
From: sofjan@aol.com (Sofjan)
[1] Re: AF - will they EVER learn?
Date: Wed Nov 18 1998

But this is unreasonable of course, and who needs it?

What THE HELLL IS THIS ???

Don't regular MF camera make the Split prims/, Micros prism and all that Focusing aids SMACK IN THE MIDDLE of the viewfinder.

Don't you ever when the light is low and the contrast is low focus with that split prism thingie and then recompose.

Don't the old 4x5 Graphic has such a dim range finder focuser that some old photographer aim it at subject neck collars to focus and then recompose !!!!

What the beef !!!!!!!!!!!!!!

You guy whine just like the horse buggy maker when they saw the Car .

Geeezzzzz
Sofjan Mustopoh
Owner of Mamiya 330f , NikonsIVa, Contax 167mt, Contax RTS and Maxxum 9xi and 8000i and Ricod GR1 and could find way to use them all Autofocus or none.

Sofjan@aol.com
Lexington ,Kentucky

From: strubpbk@rz.ruhr-uni-bochum.de (Peter Strub)
Newsgroups: rec.photo.equipment.35mm
Subject: How accurate are today's AF systems?
Date: 16 Nov 1998

Hi!

How accurate are the results achieved by your camera's AF, when exposed with maximum aperture? How does this vary with the contrast of the objects in the sensor's area?

Recently I shot some test slides, which confirmed me that images would be significantly sharper on my EOS50E with EF24-85 if focused at a longer focal length than I used for exposure, even more, sometimes it would refocus at the shorter focal length to a shorter object distance causing a slight image degradation. This effect is not very big, but with lower image contrast it will produce a disc of unsharpness of about 1/30mm on the film, which I know is often used as a reference of being sharp, but my test slides showed me, my lens and the film could do a lot better, which is important for big enlargements.

I would be happy to hear many opinions from you, especially from other EOS50-owners, but as well from different brands!

Bye,

Peter

From: w.j.markerink@a1.nl (Willem-Jan Markerink)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Can AF "see" better with a fast lens?
Date: Mon, 23 Nov 98

anonymous@siscom.net (DM) wrote:

Currently, I have a Nikon FG with a couple of manual lenses:
a 50mm/1.8 and a 28-80/3.5-4.5. I can focus much more easily and
faster with the 50mm than the zoom. I think that the speed of the lens
is a major factor.

I am looking at getting an AF camera with one lens to start. And I am
debating with myself as to what to get. Having read a lot of posts I
realize that there are pros and cons to each lens (cost, value,
quality, usefulness...) that only I can decide for myself.
   
Having no AF experience, I was wondering whether an AF camera can more
easily focus with a fast lens than a slower one (all other things
pretended to be equal)? If so, how much more?

AF is nothing more than an automated split-image manual-focus screen, with all its pro's and con's....including working faster with better light/contrast/larger-aperture, and including throwing the towel at very small (effective) apertures (teleconverters, macro etc....referred to as 'black out' with manual-focus/split-image systems). Some cameras, like the EOS-1(n)/3, switch off some 'outside' AF-sensors below f2.8....it's like having that split-image function in the perimeter of the image, and not seeing as much as in the center, in a optical/geometrical sense. Same applies to vertical sensors that use a longer/different light path, with less effective light.

rec.photo.equipment.35mm
From: "Tony Pierson" tonypierson@worldnet.att.net
[1] autofocus accuracy
Date: Sat Dec 05 1998

ed romney's excellent piece on image sharpness included a recomendation to "bracket autofocus" because he believes autofocus cameras "dont focus very well compared to MF". I am aware that they dont focus perfectly, but am curious about what the amount of error is. has anybody done any tests on this? does anyone know a link to any research demonstrating just how far off the different brands are or what situations are the worst? I have done my own tests under optimum conditions and find that my Pentax can focus faster/better than I can with my poor eyesight. But, I dont have the measurement equipment to do a proper analysis. Also, why don't the magazine reviews cover this subject? The only time I have ever seen it touched on is when Pop Photo did a casual test comparing manual to auto on the G-1 and showing that the autofocus of the camera couldnt match careful manual focusing.

I appreciate that this stuff is not important for the casual snapshooter like me, but I like exploring the technical side of it and seeing which brands/models do the best job. All the camera companies seem to gloat about the quality of their cameras, sharpness of their lenses etc, but they won't touch this subject with a 10 foot pole.

rec.photo.equipment.35mm
From: "Dan Marder" dmarder@frontiernet.net
[1] Re: autofocus accuracy
Date: Sat Dec 05 1998

I use both manual and autofucus Canon equipment, and conducted some tests after noticing that auto didn't seem to be doing as well as manual. I found that with manual focus using the best lenses, I could consistently get 100 lines/mm on film (TMAX 100). With auto using comparable lenses, it appeared that I could depend on about half that - i.e., results were random, sometimes exact but usually not. It appears that the system is designed to ensure about 50 lines/mm, about half of the lenses' capability.

I have no reason to believe that Canon is different than others in this respect.

Dan

From Nikon Digest:
Date: Fri, 04 Dec 1998
From: Richard Dong rdong@home.com
Subject: Nikons Tested in Chasseur d'Images [v04.n149/7]

I finally got my hands on the December issue of Chasseur d'Images and was quite pleased with the results of their AF shootout. For those of us afflicted with a perpetual inferiority complex, this should prove to be an excellent tonic:

F5  13 of 13 photos in focus with 300/4, closest photo @ 6 meters
    13 of 13 photos in focus with 300/2.8, closest photo @ 6 meters 

N90s 7 of 7 photos in focus with 300/4, closest photo @ 9 meters
     7 of 7 photos in focus with 300/2.8, closest photo @ 9 meters

EOS3 8 of 9 photos in focus with 300/4, closest photo @ 15 meters
     10 of 11 photos in focus with 300/2.8, closest photo @ 13 meters

EOS1n 7 of 9 photos in focus with 300/4, closest photo @ 20 meters
      8 of 10 photos in focus with 300/2.8, closest photo @ 17 meters

The following points stand out in my mind:

- - the Nikons exhibited no performance degradation with the slower, externally driven lens

- - the Nikons maintained focus to a much closer distance

- - the F5 outperformed its competition (by at least 30%) without the benefit of the MN30 nicad battery

- - the EOS3 does not quite live up to its paper specs; it should have matched the F5 in performance

rec.photo.equipment.35mm
From: dhw430@aol.com (DHW430)
[1] Re: dental photography
Date: Thu Jan 14 1999

I will keep this shorter than Dr. Hutson simply be he covered most everything well. I am a dentist and photo nut also- I shoot all formats from 35mm to 8x10 field cameras and my clinical setup is a Nikon FE/105micro2.8 lens/ and sunpack ring flash. You can get great results and keep things simple by keeping the desired magnification the same for all of your shots. I shoot at 1:2 and keep the f-stop at 22 using 100 ASA slide or print film. By doing this the photos look consistent and an AF body is unnecessary- you focus by moving the camera and lens back and forth slightly to focus. I have found that AF may seem to be easier but small differences in position can change the size of the images on film considerably at these magnifications. Both work but your images will look more consistent if the magnif. are the same from shot to shot. The choice between slide and print film solely depends on the end use of these photos i.e. for patients' records I shoot print film, for education purposes - slide film.

The other simpler thing is that it is a little harder to change things unintentionally with a manual camera since most controls are levers or knobs that have detents on them whereas an AF body like the N70 etc has buttons that can switch settings sometimes unintentionally. Each to there own, and both work very well. If you have any other ?'s please email back directly. Don

From: rpn1@cornell.edu (Neuman-Ruether)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF or Manual Focus?
Date: Fri, 18 Dec 1998

williamsg@ahecas.AHEC.EDU (Gary Williams, Business Services Accounting) wrote:

In the short time I have been following this group, I have seen many good
answers to many basic questions.  Here is mine (basic question, not good
answer):

Should the next camera body I buy be auto-focus?

I have some astigmatism, but it is not severe; I am 50 years old and wear
bi-focals, but I don't think the required correction is all that much.  My 
present camera is a Chinon CPM-6, which I rather like.  It is on extended
loan to my daughter, which is why I am in the market for a body; but I
expect to get it back one day, at which point it will be either my main
camera or a backup to the one I will get now.

I have a 50mm f1.9 Chinon lens, and a no-name 28-135 mm f3.8-5.6 zoom, both,
of course, manual focus.  I realize that I can use them on a K-mount auto-
focus body, but understand that the focusing screens in auto-focus bodies
often are not the best for manual focusing.

Probably 75-80% of my photos currently are made to document travel I do.

Any suggestions you might have on a manual/auto-focus choice would be
appreciated.                                                   

I prefer manual focus - for me, it is a faster, more direct way of focusing, and it is more accurate. BTW, on my web page (under "I babble") I describe a pair of glasses that both helped me to see better (with age-related inability to focus) and to see the camera VF more sharply. Also BTW, I find the AF "focus indicators" to be even less helpful/accurate than AF itself (try a fast wide-angle on an AF body, and focus through the correct focus point [judged from the VF, assuming it is one of the few that is sharp...] - you will see the indicators lie egregiously...! ;-) AF is OK for snap-shooting (when the lens is stopped down enough to cover its errors...), but for me, it just gets in my way (as does AE...).

David Ruether
ruether@fcinet.com
rpn1@cornell.edu
http://www.fcinet.com/ruether

From: gregnap@aol.com (GregNap)
Newsgroups: rec.photo.equipment.35mm
Subject: Old equip Vs. New
Date: 20 Dec 1998

Just a little something i've noticed in comparing my old Yashica FX2 to my new Nikon N60.

After 25 years, my Yashica died, so i went out in search of a new 35 mm system. Just checking out what's out there in my price range. Considerations, debates, etc.. led me to purchase the N60 kit. I wanted to keep it fairly affordable.

Played with the N60 for two rolls; happy with the feel of the camera, the pictures it took. Nice system for the price.

Then I took down my old Yashica for a side by side comparison. Lets' see :

No autofocus, no automatic anything else for that matter, so far i'm happy with my choice. Autoload is a great thing, don' tknow how many times i've had to open the back of the Yashica to rethread the film onto the winder. The autowinder... wonderful option. Continuous servo focus, another nicity of the N60. But after the gadgets, what was the real comparison....

My Yashica had this little button down below that my N60 doesn't have. Depth of filed preview.... only see that on the higher priced new 35mm. Lenses.. the N60 came with the f 4. 35-80 zoom, it's nice. The Yashica a 50mm f 1.4. (don't tell me how bad Yashica lenses are, I'ved used this one for years and it served me well... I don't know how many lenses could stand a naked 15 foot drop onto a steel deck and not need replacement). Also purchased a 135mm Yashica lens for the system years ago. Funny thing , it f's down to 2.8.

This is just observation. Seems like the older systems came with the better options.

Doing a country wide seach to fix the Yashica now - bad thing about old carmeras, tough on parts. Keeping the N60 too, I like the new features too much to give them up, and that's after only 2 rolls. Guess there's always a trade off with age....as I've said, this isn't complaining, just noticed this with both cameras right next to each other.

From: bwc1976@airmail.net (Brandon Campbell)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Old equip Vs. New
Date: Mon, 21 Dec 1998

gregnap@aol.com (GregNap) wrote:

 Just a little something i've noticed in comparing my old Yashica FX2 to my new
 Nikon N60.
 After 25 years, my Yashica died, so i went out in search of a new 35 mm

If you're still happy with the Yashica lenses you currently have, you can buy a new FX-3 (or perhaps even a Contax Aria) to put them on. Autofocus is nice to have for certain situations, but manual-focus will always give better value for the money (more features such as DOF preview, and faster sharper lenses). I went the other way around - started out with a new Canon Rebel G with 28-80 and 80-200 zooms, then traded the lot for a used Minolta X-700 with 50mm and 200mm primes and a big flash that can bounce off the ceiling. Sometimes I regret it, until I see how much the pictures have improved. Older camera technology combined with the newest film technology is truly a beautiful thing.

--
Brandon Wayne Campbell
bwc1976@airmail.net
http://people.unt.edu/~brandonc/

From: daverk@msn.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Old equip Vs. New
Date: Mon, 21 Dec 1998

gregnap@aol.com (GregNap) wrote (edited):

 Just a little something I've noticed in comparing my old Yashica FX2 to my
 new Nikon N60. Seems like the older systems came with the better options.

 Doing a country wide search to fix the Yashica now - bad thing about old
 cameras, tough on parts. Keeping the N60 too, I like the new features too
 much to give them up, and that's after only 2 rolls. Guess there's always
 a trade off with age...as I've said, this isn't complaining, just noticed
 this with both cameras right next to each other. 

I too have a mixture of old and new equipment. I suspect there are a lot of us around actually. My SLR system consists of a Pentax KX with a bunch of different Pentax lenses and accessories. I was given a K1000 as a teenager (still use it as a spare) and have always liked the way it handles and operates. The KX is much the same camera but more sturdy and with additional and very useful features like DOF preview and mirror lockup. All manual, all mechanical. Well, the meter uses a battery but I often pull out my dad's old Weston Master II reflective meter (still going strong after 45+ years and requiring no battery) instead anyway. I use the KX primarily for macro photography and, more recently, panoramic images created with my computer and scanner by stitching together multiple shots of a scene.

My second system is based around a Contax G2, an electronic age camera for sure. I have a blast with this thing. It goes with me to work--lots of subject matter near my office building--as well as on drives to and through the local farming communities and outlying small towns. The lenses are head of the class. With the KX my approach is careful and deliberate, while I find the G2 encourages spontaneity. For me the old and the new coexist harmoniously. I do think it's a shame, though, that more modern SLRs don't include DOF preview. Being able to actually see depth of field is one of the primary advantages of using an SLR in the first place.

-Dave-

From: "Fred Whitlock" afc@cl-sys.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Auto vs. Manual
Date: Tue, 22 Dec 1998

My point is that in both cases I controlled the settings of camera.  In the
second case, the automatic features of the camera allowed me to do so a bit
faster and with a few less steps.  "Auto" cameras do not take control away from
the photographer, they just make controlling the camera quicker and easier.
Even in full program modes, I still check the camera chosen settings and adjust
them as necessary. It still requires the brains of the photographer to make the
picture.  

No, auto cameras do not make manual control easier and faster. They get in the way of manual control. It's pretty easy to turn the aperture ring another 1/2 stop because experience tells you to on a manual camera. It's a major event dialing in the appropriate amount of exposure compensation to get to the same exposure with an auto camera. I'm not against auto cameras. Nor am I suggesting that manual control isn't possible with a computerized camera. I think it's unfair to say that manual mode on an auto camera is as fast and easy as it is on a manual camera. Good shooting.

Fred
Maplewood Photography
http://www.maplewoodphoto.com

rec.photo.equipment.35mm
From: John Sullivan jsullivan@hotmail.com
[1] More expensive for MF Nikkor lenses?
Date: Mon Feb 08 1999

Does anyone know why is it the case that MF Nikkor lenses are often more expensive than the AF ones given that they have the same focal length?

John

rec.photo.equipment.35mm
From: lbonser@worldnet.att.net (Les Bonser)
[1] Re: More expensive for MF Nikkor lenses?
Date: Mon Feb 08 1999

While these reasons are true, I also think the fact that fewer people are buying the MF lenses is a factor also. Fewer people buying means less overall profit, so they hike the prices.

fingers503@aol.com (Fingers503) wrote:

 Because they are made better. They are stronger, they are metal, they  probably
 have better glass. Pick one up, feel it, weigh it, focus it. Then try  the same
 with an auto focus. If your like most people, you will like the feel of  the MF
 nikor over the light, cheep, plastic feel of the AF.

rec.photo.equipment.35mm
From: Stafford@wind.winona.msus.edu (John J Stafford)
[1] Cold Weather
Date: Fri Feb 12 1999

I've been using mechanical, no-battery cameras forever, and the greatest difficulty I've ever had in cold weather was stiff focusing. I can handle that.

But last weekend I tried a Canon EOS Elan, auto-everything for shooting some races on the ice. It screwed up totally. Stuck, stopped. Then the owner told me that "30 degrees F" was the lowest recommended operating temp.

For real? What do you all do when shooting in cold weather (say, 20 degrees and colder)?

From Nikon Digest:
Date: Tue, 2 Feb 1999
From: Larry Kopitnik kopitnil@marketingcomm.com
Subject: re: the old question: AF vs. MF? [v04.n227/5] [v04.n228/25]

I'm sure that the list has debated the issue of MF vs. AF lenses but I'm specifically directing my question at those Nikon owners who used to own MF lenses and have bought one or more of the new Nikons bodies which really need the CPU in the lens to exploit all of the benefits of the camera.

I've owned my F3 for over a decade and it's almost a part of my right hand. I've always stayed with fast manual focus prime lenses including the 24/2.0, 35/1.4, 50/1.2, and the great 105/1.8

Recently I had the chance to get into an F5 for a great price. I also bought the 80-200/2.8 new, and an SB-28. All of the electronics are intimidating to a dyed-in-the-wool F3 user, but I'm really enjoying the challenge and the myriad of options.

MY QUESTION: (finally)
For those of you who've bought an N90s, an F5 or F100, have you migrated completely to AF lenses? I cannot afford to own both AF versions of the MF lenses that I already own and hate the idea of selling these amazing lenses which have travelled with me to the far corners of globe.

Yep, been there, done that. And regretted it.

In my case, the move involved going from an FM to an N8008S and F4. Rid myself of all manual focus lenses for new autofocus ones to be able to use the new camera bodies to their full potential. And for a time I was happy.

Then, I found myself using manual focus more and more often. Reverting to habits and ways that had proven themeselves succesful over 20+ years of photography. As the neweness of the new bodies passed, I found that for my style of photography (which includes neither sports nor wildlife; rather mostly available light shooting), adjusting exposure and focus myself just felt better. I preferred being in control of the photo and the process of making the photo. If I made a mistake, I wanted it to be my mistake, not some epoxy-imbedded silicoln chip's. The less I left to the camera's automation, the more I enjoyed making the photo.

And I found manual focus more difficult with the AF bodies. Sure, the AF screens are brighter. But the FM2 or F3 screens are contrastier. To my eye, scenes snapped into focus more assuredly with the old cameras. Manual focus was easier and more accurate -- for me -- with those viewfinders not optimized for AF. Too often, the modern controls, the lens' occassional but always inopportune focus hunting and hesitation, got in my way and became more an impediment than an assistance to capturing the image I was visualizing.

Eventually I sold the AF cameras and settled on 2 FM2s. I may yet add an F3. And I bought a 24 f/2, a 35 f/1.4 and an 85 f/1.4D (optically better than the manual focus version, to my eye), to get back into quiet, simple, indiscreet available light photography. And I'm happier than I ever was with AF.

That's not to say that you -- or anyone -- will travel the same path I did. What's right to my style of photography may or may not be right for someone else. But, based on my experiences, and what you write about the F3 being so comfortable to you for so long, I'd recommend holding onto your current lenses for now. For at least another year. Maybe add an AF lens or two as finances permit. Later, as the newness has passed and you've had a reasonable chance to see which system is most comfortable in your hands and to your style of photography, decide which lenses are really expendable.

Larry

rec.photo.misc
From: tab@IPA.FhG.de (Thomas Bantel)
[1] Re: Commentary on sharpness, a case for
+ medium format and beyond
Date: Thu Mar 18 1999

rmonagha@news.smu.edu (Robert Monaghan) writes:

 I also understand (from some earlier pop photo studies of mid-90s
 autofocus) that the accuracy of auto-focus systems in general is
 dependant on the number of AF sensors, and that manual lenses may be
 easier to focus precisely than AF systems (which may be faster). But
 again, this is a rather subjective area too, dependent of the eye of the
 holder/user. However, some systems are definitely easier to focus
 accurately and quickly, and others aren't. But I know of no existing
 standards comparing such factors. Indeed, I haven't seen any really
 useful specs on autofocus accuracy, and what I have seen suggests that's
 because the mfgers don't want us to know ;-)  In any case, most AF lenses
 have shorter focusing arcs, so they are harder to focus precisely IMHO
 than non-AF or manual focus lenses when used manually. Using a pop-up
 focusing magnifier on my 35mm and a focusing chimney (5x) on my medium
 format systems helps get the best focusing accuracy out of each lens,
 esp. when used wide open and with faster lenses...

I have once seen a test of AF accuracy with a bunch of AF bodies of various brands in a german photo mag. The results were bad enough, that I would think twice about using AF for portrait shots with very shallow DOF. Anyway, most (not all!) cameras at least managed to get the target within DOF at the largest aperture (f/1.4 I believe) at all distances they tested. Given that the usual circle of confusion size of 1/30mm isn't good for much more than a 4x6 print, things may look worse if you're after bigger prints.

Thomas Bantel

[Ed. note: regarding price differential for AF lenses...]
rec.photo.equipment.35mm
From: rnatrajan@aol.com (Rnatrajan)
[1] Re: super-wide angle opinions
Date: Mon Mar 22 1999

I saw the Sigma 14mm/2.8 at B&H during a recent visit. It's a real beauty and I am today placing an order for it. It costs $710.00 with the Nikon mount whereas the Tamron equivalent is $1199.00 (overpriced?). Since you have a FM2N which is purely manual, do you need an expensive lens like the Sigma 2.8 which has a HSM (motor) to speed up autofocus? Suggest you consider the Sigma 14mm/3.5 which is available in manual focus version for $549.95. Good luck!

rec.photo.equipment.35mm
From: benchr@teleport.com (Ross Bench)
[1] Re: af lens on manual focus
Date: Mon Mar 22 1999

I have a Nikon fe manual focus and have been offered a good deal on a af
lens will it work with the ai system on my camera

Yes it will work.

Try it out on your body before you buy it, the AF lenses are somewhat less convenient to use.

The F-stop ring is right next to the lens mount and the focusing ring can be inconvenient to use, the focusing ring may have a very short throw which can make fast focusing difficult.

From: Dante Stella dante@umich.edu
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Nikon 50mm f/1.8 or f/1.4--cost vs. performance?
Date: Thu, 20 May 1999

Ron Marvin wrote:

 
 If you plan to do much shooting in low lighting conditions, the f/1.4
 will give you an image in your viewfinder that is 50% brighter that that
 of the f/1.8. This will make it much easier to focus in low light.

From: Todd & Sharon Peach tpeach@gte.net
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Sigma and Nikon question
Date: Sat, 22 May 1999

Ala wrote:

 
 Greetings,
 I ordered the Sigma 70-300mm f/4-5.6 APO Zoom Macro Super, to use with my
 Nikon N70.  What is your experience with this lens, and would it work
 alright with the 3D metering system in the camera?

From Nikon Mailing List:
Date: Mon, 5 Apr 1999
From: "Curfman, Donald (GEIS)" Donald.Curfman@geis.ge.com
Subject: RE: TC for 300mm f/4 ED-IF AF [v04.n332/24] [v04.n334/11] [v04.n338/20]

              Nikon used to make an AF converter called the
              TC-16A.  I've played around with one a 300mm/f4.
              Optically the combination's OK, but the TC's
              AF focusing accuracy isn't acceptable on long
              lenses.

         OK I do not have the 300/f4  but I have used this
         on the 80-200/f2.8 and the Tokina 400mm. For both
         lens this TC will not AF the full distance scale-
         you must set the lens to manual focus & the body
         to S or C focus mode. Do a rough focus, touch the
         trigger to activate the AF to get the TC16A to fine
  focus.

Right. Even on a normal lens the TC-16A won't cover the lens' entire focus range.

But what my original post was saying is that with my longer lenses in combination with the TC-16A, autofocus is inaccurate even if the correct focusing distance is within the TC's range

It works OK on shorter lenses, but on both my AF 300mm/f4 and my AI 300mm/f2.8, if I carefully focus manually so the image is dead sharp, when I press the shutter release, the TC refocuses slightly in front of the subject. The result is a negative that's noticeably out of focus.

I don't know if the TC is actually causing the problem, or if the AF system in the camera (an F5) is inaccurate, and the combination of that TC on a longer lens just makes it's inaccuracy more obvious.

Whatever the cause of the problem, I don't use (or recommend) the TC-16A for long lenses -- in my opinion, the results aren't worth printing.

I'm a picky bastard though -- lots of people act proud of pictures that make my head hurt.

-Don

From: kngharv@soda.CSUA.Berkeley.EDU (Harvey H. King)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Finalizing my equipment!
Date: 8 Apr 1999

Hi!

- 20mm or 24mm or 20-35mm wide angle Nikor
I found these lenses too expensive. I was wondering why they are so
costly (speed, sharpness, contrast)! So right now I am not buying any of
these. This means I am giving away very grand landscapes.

If you really on a budget, you should consider the manual focused wide angle lens. The used wide angle lens is significantly cheaper than those you mentioned above. Furthermore, AF is a lot less critical for wide angle lens just because the apparent depth of field is a lot larger.

Why don't you try something like 20mm f/4? It's a bit slower, but it gets the focal length you needed.

Harv

rec.photo.equipment.35mm
From: Dante Stella dante@umich.edu
[1] Re: AF lenses the devil?
Date: Sun May 30 1999

On Sat, 29 May 1999 s_hutter@email.com wrote:

 (3) better focus (AF, whether active or passive, is in steps)
 How do you work that out ? (Its an analog movement isn't it)

Contrast detection is not an analog science. There was an article on this in Pop Photo a couple of years ago that showed the resolution differences in negatives shot with AF and MF. Manual focusing beat AF at up to a 2:1 advantage - on paper. It has something to do with the number of segments in the AF sensor. This is probably not an issue in small-aperture zooms with larger depth of field.

Actual results will vary, they say, because it can depend on how good your eyes are. But one thing is for sure: manually focusing on a MF screen with a microprism spot is a lot easier and accurate than having to do it on an AF camera's screen.

Active AF has always been a stepped phenomenon.

rec.photo.equipment.35mm
From: ttrust@globalnet.co.uk
[1] Re: AF lenses the devil???????
Date: Sun May 30 1999

I was really curious to understand why there "seems" to be people who
still like manual focus lenses.  Seeing that I started a little over
half a year ago, with photography.  I still don't understand why manual
focus is considered. (don't get me wrong i'm not bashing it, to each
their own)

However, AF saves a lot of time, and hassle.

Not for macro work or off-centre shooting, it doesn't. It's a pain in the neck, even with AF-lock. I use both AF and manual lenses, and 90% of the time, my AF lenses are switched to manual anyway.......

Andy

[Ed. note: shutter lag in AF vs MF and RF cameras...]
From Nikon MF Mailing List:
Date: Tue, 27 Apr 1999
From: Godfrey DiGiorgi ramarren@bayarea.net
Subject: Re: FG question

 Perhaps users with experience with both this camera and other MF Nikons
 without program mode (like the FE/FE2) or completely manual shutters (like
 the FM, etc.) could comment on whether there is any perceptible difference
 to them.  Can you handhold with slow shutter speeds better on those other
 cameras?  Is this my imagination?

SLR shutter lag: I don't know how the FG stacks up against the FM, FE2 or F3 as I've never worked with one, but all three of them are fairly quick. I think Norman Goldberg states that manual focus, manual exposure SLRs tend to be in the 30-140 millisecond lag range, with AF and auto exposure modes extending that out depending upon the camera and the circumstances of use. Manually focussed viewfinder cameras tend to be far far faster responding, with the Leica M series cameras in the 16-18ms range and the zero-lag winner being the Minox 35 at just barely over 4ms. AF/AE point and shoots tend to be cheap and slow responding.

 Maybe dabbling with a little rangefinder has piqued my interest, and next
 I'll be salivating after a Leica.  God help me.

Nothing wrong with that... there is a place where a simple manual viewfinder camera has its purpose.

Godfrey

[Ed. note: plastic AF mounts...]
From: Oscar Laborda Sanchez oscarl@abrell.ac.upc.es
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Nikkor lens help
Date: 28 Apr 1999

Anders Svensson Anders.-.Eivor.Svensson@swipnet.se wrote:

: I am under the firm impression that Nikon only makes two lenses with a plastic
: mount, both being newer AF "budget" zooms - the 35-80 and the (low cost)
: 80-200.

Add the 28-80 f/3.5-5.6 to the list.

Regards.
Oscar.

From: mcgchrs@aol.com
Newsgroups: rec.photo.equipment.35mm
Subject: AF lenses the devil?????????
Date: Sat, 29 May 1999

I feel that , although there many very well built AF lenses, my manual focus Nikkors and Zeiss lenses are far better built. I'd rather brass and aluminum than plastic and flex boards. For most of what I do, AF is not needed and most of the time MF is more accurate--meaning that I can focus where I want and compose at the same time without a computer trying to correct me.

I also use fixed lenses opposed to zooms. I like the quality of the equipment and like to rely on myself, not a computer to get the photos I want. For many people and many circumstances, AF is very good, if not absolutely neccessary. It depends on what you are looking for...

From: Dante Stella dante@umich.edu
X-Sender: dante@joust.rs.itd.umich.edu
Subject: Re: AF lenses the devil????????
Date: Sat, 29 May 1999

On Sat, 29 May 1999, babyjay wrote:

 I was really curious to understand why there "seems" to be people who
 still like manual focus lenses.  Seeing that I started a little over
 half a year ago, with photography.  I still don't understand why manual
 focus is considered. (don't get me wrong i'm not bashing it, to each
 their own)

 However, AF saves a lot of time, and hassle.
 With manual once your focused you have to set the aperture/shutter-speed
 (if your in fully manual).
 So why not save yourself one step and just worry about f/stops and
 shutter speeds.

 I would like to hear the manual focus users on this.  If it's a
 convincing argument I may just go back to manual focus.


 Thanks.

(1) Hyperfocal focusing
(2) predictability in waist-level or blind shooting
(3) better focus (AF, whether active or passive, is in steps)
(4) lower noise level
(5) more control

------------
Dante Stella

From: "David Parker" dparker@cyberport.net
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF lenses the devil???????????
Date: 29 May 1999

Well at times, I feel my manual focus stuff gives me more complete control over the image I am trying to make, also there are certain times when the autofocus just won't focus sharp enough for my taste, I have done several test on subjects using both side by side and have found a good number of times that my eye is in fact just a little bit sharper than the cameras eye.

Just my 2 cents worth..

Dave Parker

From: Todd & Sharon Peach tpeach@gte.net
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF lenses the devil?????????
Date: Sat, 29 May 1999

babyjay wrote:

 I was really curious to understand why there "seems" to be people who
 still like manual focus lenses.  Seeing that I started a little over
 half a year ago, with photography.  I still don't understand why manual
 focus is considered. (don't get me wrong i'm not bashing it, to each
 their own)

Since you're implying that you have a choice, perhaps you're shooting with Nikon gear. Nikon's MF lenses are in general better built, with metal barrels and focus helicoids (that's the screw mechanism that the focusing elements ride in). Also, there are a number of lenses (some of my favorites like the 24mm f/2.0 and 35mm f/1.4) that Nikon has not brought out in an AF version yet.

Someone else mentioned hyperfocal shooting; this has a couple aspects: the AF lenses are notoriously poorly marked for DOF scales, and many people shoot wide angle lenses by "zone focusing" (where AF can actually get in your way).

Lastly, kind of a circular argument: if you *like* to shoot in manual focus, the MF lenses have a much better feel than the AF lenses. The MF lenses have longer focus throws and a viscous "damping" to the focus ring. AF lenses typically have light, undamped, focus rings with very short throws (this boosts the AF performance).

I like both, FWIW. They're different shooting styles.

-Todd

--
Todd & Sharon Peach
Seattle, Washington (zone 7)
tpeach@gte.net
http://home1.gte.net/tpeach/NoPlaceLikeHome.htm
Owner, Manual Focus Nikon Mailing List: NikonMF@onelist.com

From: Paul paulcanada@hotmail.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF lenses the devil?????
Date: Sat, 29 May 1999

the AF lenses are notoriously poorly marked for DOF scales, and many

Indeed!. My 35-80 f/4-5.6 lens not only lacks DOF scales it lacks a focusing scale! The focusing feel is lousy as there appears to be little damping of the focusing mechanism. Optically, this lens if very good, but it is made to be autofocused. However, I must add that my other autofocus lenses (Nikkors) have a much better feel and include DOF scales and distance scales. Personally, I would get the autofocus version of most lenses and then choose manual focus when you need it. Unless I am shooting moving subjects, I usually do use manual focus.

From: mecamera@aol.com (Mecamera)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF lenses the devil?
Date: 29 May 1999

AUTO AND MANUAL

I was never a Pro in manual, and I am not a Pro in Auto. But my opinion is that manual and autofocus is a matter of taste and technicality.

Taste comes in for those that love to play with their lenses. Manual focus lenses give you that ability. You can play with those lenses, and in some instances it gives you the feeling that you are creating the image. Thus; making it more enjoyable to look at a photograph when you see how sharp it came out (that way you can say: I DID THAT! when people say that's a really sharp picture)

Technicality comes in when you see the engravings on the lenses, and when you buy into the idea that manual lenses are sharper and better than Auto focus lenses. Some people say that Leica and Contax have never gone to Auto for that reason. That if they made their lenses Autofocus, the design would make them less sharp. I don't know whether that's true or not. What I do know, is that my EF lenses are sharper than my FD lenses. Nikon hasn't made a new version of their 35 1.4, But who is to say that if they made one, it wouldn't be as sharp as the old one.

I don't mind the noise. I rather hear the noise than move the lens back and forth and loose the picture. (Don't forget that if you're ever in a place where noise is a factor. You can swicht to manual. or if you use Canon USM with ring type and rear focus, They are silent as well)

The speed? even if autofocusing is in steps. it is faster and more convenient than manual.

Accuracy? That sometimes depends on the camera, and sometimes on the lens. I took back a 400SI minolta because at infinity; it always focused one step before. I had to adjust it to the end to make the picture sharp. And I had a 28-80 Tamron Lens that sometimes in dim light needed adjustment for focusing on the wrong thing. But for the most part, Autofocus lenses are pretty accurate. My EF lenses are always right on the money.

Durability? maybe. They sell some cheap plastic lenses that I know wouldn't last forever But they always sell a well made lens for those who want sturdy lenses (EF 50 1.8 and EF 50 1.4USM)

Can you do the same with Auto than Manual? Ask the pros who have been using auto lenses for the last 10 to 15 years. And ask the manufacturers why they quit building manual lenses (those who have).

Manuel E.

From: milburndrysdale@last.com (Milburn Drysdale)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF lenses the devil?
Date: Sun, 30 May 1999

Autofocus or manual lens? I need both.

I've been buying a new autofocus system to replace the fine manual system I've used professonally for years (and years and years). My eyes are focusing less quickly now, and I want to shoot live & moving subjects more easily.

My plan was to sell off the manual lenses & bodies as I acquired autofocus (and autoexposure) ones.

But as I become accustomed to the automation - and it IS much better than I had expected - I am also realizing the limitations of it. I have judged my own exposure settings for so many years that I factor-in contrast adjustments and reciprocity calculations without even slowing down to realize that I've done it. I preview a scene and decide where I want to drop the depth of field versus the shutter speeds available, again, without losing a beat of the shooting rhythm.

When I then must stop to decide WHETHER I must override the auto system, and HOW to best override the auto system, then I've lost more time (and rhythm) than if I just shot in manual.

For those shoots and those shots, I want manual, and auto lenses on manual settings just don't feel right: too short a throw and not the right view screens.

ON THE OTHER HAND I've almost always missed the fun shots. The magic moments when something goes wrong and the talent actually really honestly LAUGHS! And I want to capture those times too. I want the spontaneity that an auto-everything camera can offer.

So I'm buying a top auto system AND I'm keeping my manual system. Man, this is costing a fortune. AND it weighs a ton.

From: rustyrd@my-deja.com
Newsgroups: rec.photo.equipment.35mm
Subject: MLU, the F100 and nikon marketing
Date: Sun, 30 May 1999

For all the people who don't feel that Mirror Lockup is all that necessary, may I suggest you read an article on page 18 of the June '99 issue of Popular Photography regarding some "fairly" in-depth testing by the author on the F5 using it with and without Mirror Lockup. As the tests show, although by no means conclusive, the Nikon F5 specifically using telephoto lenses, mounted on various tripods and using various support techniques, shows sharpness gain of anywhere from 13% to 172% when using shutter speeds between 1/8 and 1/60, and at 135mm, 300mm, and 400mm. Let me just that I know some of you may poo- poo the article simply because it appears in Popular Photography, but before you completely discount what this author has done, and the test results that he achieved, let's see just how many of you can come up with similar tests done just as carefully as he has done that prove him wrong!!

From: John Halliwell john@photopia.demon.co.uk
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Are manufacturers right...nobody really cares about DOF???
Date: Sun, 30 May 1999

Anthony mxsmanic@hotmail.com writes

I like having a choice of DOF and a way to preview it.  I use it sometimes.
However, my point is that, if these things were not available, they would
hardly be _necessary_.  You use what you have.  Saying that you cannot get
good photographs because you don't have the right flexibility for DOF or a
way to preview it is an excuse for a lack of talent.

I've jumped into the thread half way through and apologise if this has already been mentioned but...

Nobody seems to have mentioned that there's more to DoF preview than just the depth of field. If your using some filters (viginets immediatly come to mind) you need DoF to see what your image is going to look like (unless your shooting wide open). The difference is amazing as you stop the lens down, making the choice of aperture easy.

There's probably loads of similar reasons why it's necessary to get the best out of photography. It's not essential for snap shots, but can really come in handy!

--

John

Preston, Lancs, UK.

From: Pál Jensen paal@norvol.hi.is
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF lenses the devil?
Date: Sun, 06 Jun 1999

s_hutter@email.com wrote:

 AF lenses can be made just as "Sharp" as MF lenses,
 After all, The only real difference between AF and MF lenses is, One
 is powered by your fingers while the other is powered by the motor in
 the camera (Or lens body)
 The way that they are driven is not really going to effect how sharp
 they are, That's down to the optics in use !

From: robertmcca@aol.com (Robertmcca)
Newsgroups: rec.photo.equipment.35mm
Subject: Are manufacturers right...nobody really cares about DOF???
Date: 24 May 1999

When I purchased my first autofocus camera system a few years back, I was disheartened by the lack of useable (or in the case of zooms, any) depth of field scales on the lenses. That, plus the lack of depth of field preview on what was then Minolta's top-of-the-line 8000i (the camera I bought), seemed grossly negligent.

I rarely hear much lamenting among photographers about this. Just curious, does anyone else out there miss having this depth of field info, or am I just showing my age?

Bob

From: rmmm9999@aol.com (RMMM9999)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Are manufacturers right...nobody really cares about DOF???
Date: 24 May 1999

Bob,

I also greatly appreciate the DOF preview.

I also use and like the 8000i, but I am disappointed that it lacks DOF preview.

It is not impossible to put onto an autofocus camera. Several of my Canon autofocus cameras (e.g. Elan IIe) have an electronically stopped down DOF preview, which I greatly appreciate. Some Nikons also have DOF preview----I don't know about other Maxxums.

*********************

Many or most of the autofocus lenses have deleted the DOF scale because of these factors:

1. The internal mechanics of the lenses are very different than older lenses, including the fact that most go from closest focus to infinity in a VERY short turn (to save power, and to speed operation)

2. Manufacturers assume speed of use is primary for autofocus users

3. It would complicate design and thus add to cost to have DOF scales that are reasonably accurate in the less expensive lenses. I presume that lenses made for pros are more likely to still have the DOF scales--am I correct?

4. Even when a DOF scale is present on an autofocus lens, I have my doubts about its correctness, since their focus scales are so goofy.

good shooting!

Richard

From: Pál Jensen paal@norvol.hi.is
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF lenses the devil?
Date: Thu, 10 Jun 1999

dynax_9@email.com wrote:

 It would seem that many people on this NG are sadly stuck in the dark
 ages.

 To say a lens is sharper because it is MF rather than AF is total
 rubbish !!!

 I am sure that the lens makers can make a lens just as sharp whether
 it be MF or AF !!!

The tolerances in common lenses are measured in 1/10's of a millimetre. Many AF lenses have moving and rattling lensgroups that moves much more than this amount. There's no doubt that if the same lens were constructed tightly with high precision the results would have been even better. This loose construction is probably also the reason for the apparently much higher sample to sample variation often reported for AF lenses. However, more often than not the lack of precision is more than compensated for by DOF, but its still a factor for those who shoot wide open focused at infinity.

It is possible to make tight AF lenses. However, its probably too expensive and/or compromise AF speed too much to be done on a consistent basis. You may then have needed more powerful AF motors. The tight ones I've seen has been super telephoto lenses. Loose lensgroups such as seen on many wider lenses would have made a super telephoto lens useless.

In 1997 there was sold a little more than 700 000 slr's on the world market. 20 years ago Pentax and Canon made each that number a year of their most popular SLR model. Lenses are now cheaper than ever in spite of being more complicated and manufactured in lower volumes. The profit marging on SLR camera and lenses has been greatly reduced in a shrinking market and price has been the agressive competive factor. Cameras are now cheaper than ever. It has a price.

From: hrphoto@aol.com (HRphoto)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF lenses the devil?
Date: 10 Jun 1999

The tolerances in common lenses are measured in 1/10's of a millimetre.

That is a very conservative figure. With some lenses, in order to be able to take full advantage of their performance potential, mechanical tolerances in the lenses as well as the cameras need to be held to 1/100's of a millimeter. Granted, that is beyond consumer equipment, but it further underlines the shortcomings of current autofocus technology.

Heinz
HRphotography
http://hometown.aol.com/hrphoto/myhomepage/index.html

From: Pál Jensen paal@norvol.hi.is
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF lenses the devil??????
Date: Thu, 10 Jun 1999

"Dirk J. Bakker" dbakker@mindspring.com wrote:

 Anyone that is more concerned about convenience than that final image is not
 very serious in my book.

True enough but I'm not so sure that AF is more convenient than manual focus provided that you know what you're doing. For telephoto lenses AF can be alright.

Let's say that you use a 50mm prime lens. When you press the shutter for AF to take place you have to decide whether the subject that happens to be where the AF sensor(s) are pointing is representative for what you are going to shoot. If not you have to point the camera in another direction, press the shutter release and AF and then recompose. Then you have to decide whether this setting give you the desired depth of field with the aperture you or the camera has choosen; if not you have to find where in the subject you must place the AF sensor(s) in order to get the desired depth of field with the choosen aperture. Then you have to repeat the procedure above and again recompose before you actually shoot the picture. Whats so convenient about this. Its faster to do this manually. I take for granted thet people actually care about whats in focus in their images.

From: "Spock's Brain" another@world.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF lenses the devil????????
Date: Thu, 10 Jun 1999

...

You managed to make a three step process for most people into something really complicated. Step one: point camera at subject and press the shutter halfway, step two: if subject isn't where you want, just hold the shutter release down to lock focus then recompose where you want the subject to be (this of course requires you to be in single servo AF, but then if you're shooting something that moves, you're not going to be recomposing much in the first place), step three: take the shot - depending on your subject and your camera, step 2 is optional. I've yet to see a manual system allow you to judge DOF any easier than AF systems - both require DOF preview or DOF markings on the lens and a knowledge of aperture settings. It doesn't require these gymnastics to use an AF system. Learn to use it instead of fight it.

From: "Cyberferal" prdol@alphalink.com.au
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF lenses the devil??????????
Date: Thu, 10 Jun 1999

.....

For starters, I do own and use an AF SLR, so I will NOT say I don't like AF. But, to answer your question, here is one application where manual focus will give me better results EVERY TIME.

I do a lot of landscape photography, often requiring big depth of field and control over what will and will not be in focus. With a prime (ie not zoom) MF lens which has depth of field markings, and judicious use of the depth of field preview, I can setup a photo exactly the way I want it. The end effect will be exactly in focus as predicted (since I select the aperture). Now my AF camera will look at whatever happens to be in the AF gunsight and NOT give me an in-focus confirmation. This is because as far as it is concerned, the subject is out of focus. But of course it is too stupid to realise that the aperture will result in a certain depth of field. I have yet to see an AF system where you can point the camera at a background element (say it's near infinity), then a foreground element (say 3 metres away) and the camera will realise that both are supposed to be in focus, and so select the appropriate focussing point and aperture to ensure both items are in fact in focus. If there is one, then please let me know.

Otherwise, I will be back to my tried and tested MF method.

[Ed. note: a few Canon and other AF cameras have this feature, but not all!]

From Nikon Digest:
Date: Mon, 26 Jul 1999
From: Rob Stapleton foto@greatland.net
Subject: [NIKON] 20mm 2.8 AF

Have any of you had any problems with the 20mm F/2.8 AF? I just got a repair estimate on a lens that was mint 9+ conditions, always capped and kept in a lens pouch, never dropped or banged by other cameras that had the elements come loose. Repair estimate $235, book on the lens is $350 used. I am kind of put out that as a non shock repair of a lens that had loose elements was not covered by some original warranty, or at least a manufacturers repair. If all lenses have the elements falling out, I wonder if professionals can start leasing lenses....RS

Rob Stapleton Photojournalist/ Anchorage Alaska http://airlinebiz.com/anc

From Nikon MF Mailing List:
Date: Thu, 29 Jul 1999
From: "Peach, Todd S" Todd.Peach@PSS.Boeing.com
Subject: [NIKON] 20mm AFD that fell apart

I've lost this thread, but there was a PJ in Alaska who wondered how his otherwise good-looking 20mm AFD lens could fall apart. It has not ever been dropped, etc.

I'll offer up an anecdote: I had a lens fall apart that had never been "abused". The culprit was vibration. The lens had traveled by airplane with me, and had been allowed to rest against the airframe (not in a bag). The vibrations in airplanes wreak havoc with small screws, and perhaps with glued assemblies as well.

Lots of air travel in Alaska........
Todd Peach
B-XT34 Information & Server Development for Labs
Boeing Commercial Airplane Lab Test
M/S 19-MH Phone: (206) 662-0921

From: rlsaylor@ix.netcom.com (R. Saylor)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: depth of field scales missing on lenses?
Date: Sat, 17 Jul 1999

alaica@tir.com wrote:

     Can anybody tell me how you manage to set a hyperfocal distance
when so many of the new lenses(especially zooms) dont bother to include
a depth of field scale?

It's frustrating when technology obscures what used to be a simple, extremely useful photographic concept, essential for landscape photography.

You can make yourself a hyperfocal chart for your most-used focal lengths, use a dof slide rule, or carry around a pocket calculator.

There's a short hyperfocal table at

http://bobatkins.photo.net/info/doftable.htm

There's a hyperfocal calculator at

http://www.frii.com/~mbaltuch/

and another one at

http://www.outsight.com/hyperfocal.html

There's information about a hyperfocal slide chart which you can purchase at

http://members.aol.com/Photoinfo/index.html

Richard S.

 JamesBishop wrote:

  I am about to purchase my first SLR camera and am seriously considering
  the Nikon N70.  I am  looking at the Nikon 28-105 f3.5-4.5D Zoom-Nikkor
  lens.  Any feedback is solicited.

I've just noticed that the N70 doesn't have a depth of field preview button. You'll need this if you plan to use graduated neutral density filters. You won't be able to tell where the dark part of the filter begins until you stop down the aperture with the preview button. The N90s is the next step up that has a DOF preview button.

I like the Nikkor 35-70mm f/2.8D zoom lens. It's a brighter lens with the same brightness throughout its range.

Both these suggestions are more expensive than what you've outlined, but you get more.

Good shooting with whatever your choice is.

Bill Welch

rec.photo.equipment.35mm
From: "Fred Whitlock" afc@cl-sys.com
[1] Re: Nikkor AF vs. AIS
Date: Fri Aug 27 1999

Optically, the AF Nikkors are as good as any Nikkors ever made. Some are better. Mechanically they are significantly inferior to the metal helicoid manual focus lenses. To date, I have worn out 3 AF lenses. What that means is they stopped functioning properly from wear and tear (not abuse) and had to be replaced. I've never worn out a metal helicoid lens.

I carry AF Nikkors anyway since they are lighter in weight and it's worth it to me for that reason. If they weren't I probably wouldn't own one. For the occasional use an amateur would apply to a lens, the AF Nikkors are probably good for a lifetime. Good shooting.

Fred
Maplewood Photography
http://www.maplewoodphoto.com

DanielOC oconneld@ab-controls.com wrote

 Besides cost, are there any differences between Nikkor's current Auto and
 Manual focus lenses?

 (ie., optics; mechanics, durability, etc.)

 I am curious if there are any benefits to spending the extra bucks on the
 AIS 24mm, 50mm, 85mm, 105mm for use with an FM2 or F3.

 Thanks...

Hi Everybody!

Here's an interesting eBay item. Someone has (I've no connection, BTW) dozens of broken Nikkors, all but two are Automatic Focus plan jane zooms or normal fixed lenses. Item no. is 175045215.

I was curious about an important issue, gear reliability. Do these auto focus lenses break down more? Are they more difficult to repair than the manual focus ones? Will those old MF Nikkors be working 50 years from now, while the AF models are in the landfill?

Will Nikon eventually quit making manual focus glass?

Cheers,

Rich Lahrson
tripspud@wenet.net

my experience with the 75-300 and the F5.
To sum it up, the auto focus performance is extremely terrible. i have never
seen a lens hunt as much
FWIW, the same lens performs much faster on both our F4S and the F4E.

From Nikon Digest:
Date: Wed, 08 Sep 1999
From: "Markus Salin" markus_salin@hotmail.com
Subject: [NIKON] AF 50/1.8 (Made in China) normal tolerances?

Hello Everybody,

I just bought an AF 50/1.8 (Made in China) lens and was quite disappointed with the mechanical feel of the thing. When I put even very little left-right force to the focusing ring it moves a fraction of a millimeter very easily and the lens assembly moves with it. The actual turning of the ring when focusing is OK, but it is very difficult to operate the ring without putting a bit of lateral force to it at the same time. As a result I hear and feel a little clack when operating it in manual focus mode. The real worry is that this play is slightly visible in the viewfinder as well, because the whole lens system can shift and maybe also turn! What effect might that have on the picture quality.

Is this normal for this exact model (China, summer -99) or do I have a warranty issue here?

Yours,
Markus

From Nikon Digest:
Date: Mon, 6 Sep 1999
From: Larry Kopitnik kopitnil@marketingcomm.com
Subject: Re: [NIKON] Autofocus Accuracy

Furthermore, it seems to me that ultimate AF accuracy is or will be more easily obtained using some form of ultrasonic technology, whether it be from N or C. Any thoughts from the group?

Jim Williams (jlw@nospam.net) is one of the relatively few posters to usenet whose writings I've come to admire. He made the following post to rec.photo.equipment.35mm on March 24th this year, in response to a query. The last parpagraph in particular partially addresses your question, so it may be of interest. All of the following in Jim's post:

A "Silent Wave Motor" is Nikon's term for a piezoelectric ring motor -- the same thing Canon calls an "Ultrasonic" motor.

Both work the same way. There's a smooth outer ring attached to the focusing mechanism of the lens, and a toothed inner ring that's carefully dimensioned to fit just inside the outer ring without quite touching it. On this inner ring are segments of piezoelectric material. A high-frequency oscillator circuit sends current around the inner ring, stimulating each segment in sequence. The current causes the piezoelectric material to distort the ring, just enough to bring its teeth into contact with the outer ring. This progression of ripples around the inner ring carries the outer ring along with it, causing it to rotate the focusing mechanism.

If that's hard to visualize, have you ever seen those many-legged insects that run along the ground with a rippling motion of their legs? Imagine a bunch of those insects getting together and bending sideways so they form a ring, with one continuous set of legs on the outside. Now imagine putting the insects into a tiny horizontal "hamster wheel," just large enough that their outside legs barely touch it. If the insects work together, they can rotate the wheel by sending sequences of ripples along their outer row of legs.

A big advantage of this kind of motor (the one with the piezoelectric material, NOT the one with a bunch of insects -- yecch!) is that it produces high torque at low RPM; that makes it quiet compared to a conventional low-torque, high-RPM DC motor that has to be slowed down with a noisy train of reduction gears. Another advantage -- at least for some forms of this motor -- is that you can turn the focusing ring manually whenever you want, even if autofocus is engaged; this is because the clearance between the inner and outer rings is just enough to allow the outer ring to turn freely when no piezoelectric ripples are running around the inner ring. It also makes it easier to design some kinds of lens, because the designer doesn't have to allow for a power shaft running back to the camera body.

Contrary to popular belief, though, a piezo ring motor isn't necessarily faster or more efficient than a similar system with a regular DC motor in the body. All other things being equal, the power of an AF motor (hence its speed of operation) depends on only one thing: the energy available from the battery. So, assuming that a piezo motor in a lens and a DC motor in a camera body are equally efficient (actually, if anything, the efficiency probably favors the DC motor; the piezo motor uses a lot of its energy distorting the toothed ring, rather than moving the lens)... and assuming that the other inefficiencies cancel each other out (yes, the DC motor requires a power shaft from the body, but the piezo motor requires longer electrical conductors from the body) an in-lens piezo motor and a body-mounted DC motor will have exactly the same performance IF they're powered by the same type of battery. Canon has done a good job of brainwashing photographers into thinking in-lens motors are *always* faster and more efficient, when in fact that is not the case!... their big advantages are quietness and convenience, rather than sheer performance.

------------------------------

Date: Mon, 06 Sep 1999
From: tired.of.spam@invalid.com (Rudy Garcia)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF problems page URL etc.

....

Another conclusion to be drawn is how poorly an AF camera screens performs when used for manual focusing. Old MF camera screens, although "dimmer", "snapped" the image into focus, whereas the brighter AF screens do a poor job of it. This is a well known fact known to those of us that like to do some macro work once in a while.

--
Use address below for Email replies.

"Rudy Garcia" rudyg@jps.net

From Nikon Mailing List:
Date: Fri, 08 Oct 1999
From: John Albino jalbino@jwalbino.com
Subject: Re: [NIKON] Manual Focus Lens -> So Expensive -> WHY?

Toom wrote:

>The subject said so..
>Why are the manual focus lenses of Nikon so expensive compared to AF?

Perhaps for several reasons, including marketing. The marketing one first:

Nikon may want to push consumers and lower-budget photographers to the AF line rather than having them "hang around" the "old" MF lenses. Only photographers who have specific needs for MF lenses will continue buying them; anyone else will shop the MF used market, and Nikon doesn't get any money from the used market. As demand drops for MF, Nikon can better justify discontinuing them completely.

Next, MF lenses probably are significantly more expensive to manufacture than AF lens, just because they were designed for production procedures (and durability standards) of decades ago. Since they use more metal than AF lenses (in general) the raw materials costs are probably higher as well. Automating the manufacture of MF lenses to the same degree as AF lenses would require a lot of R&D;, retooling, etc. and is probably not cost-efficient.

There is a much larger market for AF lenses then for MF lenses, meaning the economies of scale provide for a larger base to spread the costs. Although the MF lenses' development costs should have been amortized a long time ago, the raw materials are bought in much smaller quantities and thus are more expensive. The tools and dies are older, and possibly impossible to replace, while the newer AF lenses use more modern tooling.

Just some thoughts. Probably others can add more.

- --
John Albino
mailto:jalbino@jwalbino.com

rec.photo.technique.people
From: Tom Van Veen tvanveen@accmail.umd.edu
[2] Re: AF problems page URL etc. Re: Focus Auto or Manual?
Date: Sat Oct 09 1999

Robert Monaghan wrote:

> I agree that I usually use a 105mm range lens for portraits, but I have
> also used longer teles (and 20mm and 24mm for that matter)...
>
> you might check out the Autofocus Problems page for more on AF problem
> issues such as the problems with narrow depth of field focusing issues,

Thanks for the link Bob. I found the info regarding the usefulness of AF camera focusing screens particularly interesting.

I would like to point out that on this page you say "Pentax provides for using some older K and KA mount lenses on their newer AF cameras too."

Actually, *every* Pentax K mount lens will work on any Pentax k-mount body ever made, with one exception. Pre-"A" lenses will not meter correctly on the MZ-50.

Thanks.

tv

From: "Gary Dewyn" g.dewyn@worldnet.att.net
Newsgroups: rec.photo.technique.misc
Subject: Re: Nikon School: Underexpose slides on purpose?
Date: Sat, 4 Sep 1999

What if the camera has undefeatable DX circuit like my Pentax PZ-70? If I try to "disable" the circuit by putting tape over the contact area of the canister the darn thing defaults to EV100! You can't override either. So I shoot what the DX reads and just adjust the f/stop.

Gary

Brad Mitchell frbradjm@gte.net wrote

> I see this exposure tweeking stuff discussed in discussion groups all
> the time (i.e. shoot Velvia at ISO 40 or 50?). Unfortunately, "rules"
> like this are not practical when camera meters are not consistent, even
> within the same camera make and model.
>
> As suggested in most basic instructional photography books, you should
> calibrate each of your camera's meters to each type of film you shoot.
> Check out one of the John Shaw photo books at the library and follow the
> simple instructions (usually in the first or second chapter).  Take 
> careful notes and put a peice of tape on the back of your camera cross
> referencing the film type to the desired ISO.  You may have to do this
> for each film type you shoot for each camera you have.
>
> I know of photographers that shoot Velvia anywhere from ISO 32 to ISO
> 100 depending on which of the 4 cameras they own is in use.
>
> Hope this helps,
> Brad Mitchell
> bradjm@gte.net
> http://home1.gte.net/bradjm/Photo.html

....

From: Gary Frost gfrost@home.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Updates AF users won't want to see ;-) Re: AF problems page URL etc.
Date: Sun, 05 Sep 1999

Your data seems to agree with my experience with an 8008s. I have 20/20 or better vision without glasses and was able to focus more accurately using the viewfinder than the autofocus confirmation. I also noted a significant 'deadband' where I could move the focus ring and the AF confirmation would still say it's in focus. Allowing AF to do it's thing would sometimes get it right on and other times was visibly soft.

Gary Frost

Robert Monaghan wrote:

> those of you trying to use AF cameras with their "in-focus" indicators as
> guides may want to give up after reading the latest updates and tests at
> AF problems page at http://www.smu.edu/~rmonagha/third/af.html (draft)
>....

From: spoorl@aol.com (SpooRL)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Updates AF users won't want to see ;-) Re: AF problems page URL etc.
Date: 05 Sep 1999

>able to focus more accurately
>using the viewfinder than the autofocus confirmation. 

If I focus back and forth manually using one of my my F4s bodies, I can detect a tiny bit of latitude in what the electronic rangefinder indicates as the target focus point. Perhaps it has to do with the area actually included in the reading--not a pinpoint. Or perhaps it's just a sloppy device. It reminds me of what you see in manual exposure mode if you move the aperture back and forth near the "target" (+/-) exposure setting indicated--a little bit of latitude there, increasing with film speed. At ISO 25 it's about 1/3 stop. I fish around and get its midpoint. I wonder if autoexposure seeks the midpoint or settles at random on a point within the latitude bracket revealed in the manual mode.

If I've got time, I usually focus with the F4s manually and then depress the shutter halfway to see what the rangefinder says. Nine out of ten times it fails to match.

I would use even the best autofocus only in situations where I knew that manually focusing was futile or a crapshoot at best.

Spoo

From: Keith Hollister keith_h@mindspring.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Updates AF users won't want to see ;-) Re: AF problems page URL etc.
Date: Sun, 05 Sep 1999

spoorl@aol.com (SpooRL) wrote:

>If I've got time, I usually focus with the F4s manually and then depress the
>shutter halfway to see what the rangefinder says. Nine out of ten times it
>fails to match.

I had an F4 before my F5, and would occasionally notice the same thing. The interesting point is that every time I have tried that with my F5, the AF focus indicator lights green after manually focusing. Appears there is some technology progress.

On the larger issue of AF vs MF, I do not get results which match the tests in Pop Photo. If I AF on a medium contrast flat object from 8-10 feet away, even movements of 2-3 inches result in refocus. I respect Kessler, but I have no idea how Pop Photo got the results they report. It will be interesting to see the manufacturer's responses in the upcoming issues:-)

Keith Hollister
keith_h@mindspring.com

From: golem@shell.acmenet.net (David Rozen)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Good inexpensive AF lens
Date: Tue, 07 Sep 1999

Jauvid Ayadi (ayadi@worldnet.att.net) wrote:

: looking for inexpensive and good (is there really such a thing!)
: lens (pref 28-300) for my Minolta Maxxum. Any recomendations?

Very simple. There is only one, which comes in about 4 different brand names, and it *IS* rather inexpensive. It's also the very best in its range ;-)

Regards, - dr

From: spoorl@aol.com (SpooRL)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Updates Re: AF problems page
Date: 07 Sep 1999

>From: rmonagha@smu.edu (Robert Monaghan)

>Using AF, you averaged roughly a 12%+ loss in resolution compared to
>using manual focusing at the target, ranging from a tie to a loss of 38%
>of resolution (e.g., 47 lpmm manual focus vs. 29 lpmm using AF). So AF >is
>not as accurate as MF, even on an AF camera, and it can be a lot worse!

I would like to see data produced using a three-dimensional target, to circumvent that dodge.

The F4s has a nice bright screen but it is always a relief to get back to an F3 to focus critically. Looking through the F4s finder puts considerably more strain on my eyes, and makes me kind of queasy after a while. If you've watched the "Newtons" or whatever they are swirl around for long enough you kind of want to throw up.

There is no basis for statements favoring the use of autofocus by default. The argument to use autofocus for all work because it is easier--lazier--seems inconsistent with the usual desire of an artist to produce the best work possible. It makes about as much sense as saying leave every light on in your house, day or night--because it's easier. It's a completely nonsensical argument if the goal is excellence.

Spoo

From: swansond@netcom.com (Dennis Swanson)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Updates Re: AF problems page
Date: 7 Sep 1999

....

After reading this I had to try this with my manual focus Minolta body with the split-image viewfinder to see just how bad this amount of error is. With the 50/1.7 lens, I focussed on a harshly-lit sharp vertical corner, at about 10 feet. Then I dropped a ruler on the floor and stepped back 12 inches. I could just barely make out that the two halves weren't perfectly aligned. (At 18" it was obvious, and at 6" I could not tell a difference.) This tells me that AF evidently isn't perfect, but is not quite as bad as it sounds. (I rarely lug a tripod around so I'm already losing precious lpm's.)

Den

--
Dennis M. Swanson

[Ed. note: since the 50mm primes had in-focus ranges of 17, 29, and 44 inches depending on brand, we can assume that if it was obvious at 18 inches, then it would be pretty obvious at the endpoints of most manual and AF focusing systems, right?]

From Leica Mailing List:
Date: Sun, 10 Oct 1999
From: Godfrey DiGiorgi ramarren@bayarea.net
Subject: re: [Leica] R8 Shutter release time lag

I seem to recall Norman Goldberg measured the Leica M6 with 17ms and the Minox 35GT with an amazing 4ms.

Godfrey

>From Popular Photography's test of the R8, published in their July, 1997
>issue, under the heading "System Time Lag": "Tested with 50 mm f/1.4 lens
>at EV12, aperture-priority mode at f/5.6. Time between pressing shutter
>button and actual exposure is commendably short at 125 ms."
>
>Other Pop Photo time lag test results for comparison:
>Canon EOS 1N: 229 ms (doesn't specify Manual Focus or Auto Focus)
>Canon EOS Elan IIE: 210.5 ms (specifies this is in MF)
>Contax AX: 80 ms in MF, 430 ms in AF
>Contax RTS III: 70 ms
>Contax G2: 160 ms in MF, 180 ms in AF
>Nikon F100: 140 ms (doesn't specify AF or MF)
>Nikon F5: 72 ms in MF, 330 ms in AF

From: "J. S. Oppenheim" commart@smart.net
Newsgroups: rec.photo.technique.people
Subject: Re: AF problems page URL etc. Re: Focus Auto or Manual?
Date: Sat, 09 Oct 1999

My AF camera is a Nikon 8008, and I've found using the feature a pain in the butt about 50 percent of the time. For one thing, I seldom center my subjects, so right off the bat, my routine is to compose, move the camera to an auto-focus target, and recompose; also, my month consists of a lot of diffuse fields, either on the water (clouds and open sky), or with a model (soft focus, soft fabrics), and AF doesn't work with any efficiency on low contrast surfaces; finally, even in event and travel journalism, managing the arrangement of several people across the frame or situated in the depths of it is really too difficult for my more than a decade old AF technology. At least half the time, I have to switch to manual focus to shoot efficiently. This doesn't mean I would dump the feature--it has been an absolutely great asset for shooting the candid parts of weddings and for snap shot fast "close-up" photography using a Nikkor 28mm 2.8.

//Jim

....

[Ed. note: a correction re: Pentax autofocus lens interchangeability etc.]
From: Tom Van Veen tvanveen@accmail.umd.edu
Newsgroups: rec.photo.technique.people
Subject: Re: AF problems page URL etc. Re: Focus Auto or Manual?
Date: Sat, 09 Oct 1999

Thanks for the link Bob. I found the info regarding the usefulness of AF camera focusing screens particularly interesting.

I would like to point out that on this page you say "Pentax provides for using some older K and KA mount lenses on their newer AF cameras too."

Actually, *every* Pentax K mount lens will work on any Pentax k-mount body ever made, with one exception. Pre-"A" lenses will not meter correctly on the MZ-50.

Thanks.

tv

....

From: "Sergey Nosov" nosov@fnmail.com
Subject: Re: Is Nikon F100 worth it? (Autofocus)
Date: Sat, 21 Aug 1999

> I have used my F100 and a 300mm lens to track birds with excellent results.
> I can't imagine it not working for an airshow.

Shooting birds you're probably about 5 meters away from them. Correct me If I am wrong, please.

At airshow you are bouncing on the edge of infinity setting. Autofocus generally performs well at the mid-range, and not so well if subject is too far or too close.

Date: Mon, 23 Aug 1999
From: wvl wvl@marinternet.com
To: Robert Monaghan rmonagha@post.cis.smu.edu
Subject: AF & MF

Bob, just a note to say, like Jim Brick, I agree 100% with you about MF lenses. I just finished a world trip with M3, Fuji GS645 and Fuji GSWII690. Great results with these rfdrs. I also shot a GR1 Ricoh a lot and did indeed have quite a few out of focus shots. That's the only AF camera I ever owned so I don't know if it is typical, but, I need to put the plane of focus where I want it.

Bill Lawlor

From: CHRIS HO "chrisho"@teleport.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Nikon F4s autofocus capabilities
Date: Thu, 21 Oct 1999

Choiliefan wrote:

> >Is the F4s' autofocus speed affected by the type of AF lens used?
>  
> I understand the F4 focuses extremely fast using the newest lenses with
> built-in silent wave motor.

I own an F4s, and though the new AFS lenses increase the F4's capabilities in some situations, there are times when the lenses actually out run the lens and confuse the AF software as a result. I once tried out the new AFS 600, 4.0 with my F4, and the AF would hunt like crazy because the lens was moving too quick for the F4 to keep up with. The F4s has a decent AF system for most situations, but the F5 and F100 will stomp all over it when shooting fast moving subjects.

-Chris

CHRIS HO
Email: chrisho@teleport.com

From: Todd & Sharon Peach tpeach@gte.net
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Nikor Manual vs Autofocus (not trolling)
Date: Fri, 22 Oct 1999

I use a happy mix of MF and AF lenses and bodies.

Somebody mentioned that AF bodies don't have focus screens that work well with MF; I heartily agree. My current favorite MF setup is a Nikon F3 with an E screen. I use this extensively with my MF 35mm f/1.4, MF 24mm f/2.0, and my AF 85mm f/1.8. There's something about focusing on the 'whole screen' that is pleasurable to me, and very fluid for the 'focus compose' cycle. AF, no matter how sophisticated, tends to drive one into a 'focus-recompose-shoot' cycle. On MF, if you use the whole screen to focus, you tend to focus and compose at the same time. The older screens / cameras have more 'tooth', better suited for evaluating focus.

FWIW, I've not been disappointed on (Nikon) AF cameras with MF lenses by letting the electronic rangefinder determine focus; it's accurate, it's just a bit slower than doing it via the focus screen on an MF camera.

-Todd

--
Todd & Sharon Peach
Seattle, Washington
tpeach@gte.net
http://home1.gte.net/tpeach/NoPlaceLikeHome.htm

From: "Robert Bodde" bodde@a1.nl
Newsgroups: rec.photo.equipment.35mm
Subject: Re: N90S: Lengthy focus search = low batteries?
Date: Fri, 22 Oct 1999

Even with the big barrels on it, like a 80-200 f2.8, you should get at least 16 rolls of film on one set of 4 penlite (AA) batteries. The AF works on the Infrared light of the SB26, and that's why it is slower

Robert Bodde

> Clarence Tittletooper tittletooper@com.com wrote
> > Shooting flash snapshots with N90S and SB28 last night.
> >

> > As the eveing progressed, the N90S seemed to take longer to decide on
> > correct focus before allowing the shutter to trip.
> > The LCD battery indicator still shows good power, but could the
> > focus-delay be caused by less-than-brandnew AA batteries in the N90S? 

From Manual Nikon SLR List:
Date: Fri, 22 Oct 1999
From: Richard Lahrson tripspud@wenet.net
Subject: Delay Caused by Autofocus

Hi everyone!

I've been carrying and using my first autofocus camera, an Olympus Stylus Epic. I've used manual focus cameras previously of all sizes. Upon pressing the shutter release there is a definite time lag before the exposure while the autofocus operates. Even worse is the 'anti-red eye' mode's time lag of these p&s; cameras.

Is this also true of Nikon's autofocus cameras? For example, on the F5, I suppose the autofocus can be disabled. Autofocus may be great at times, but it makes capturing an exact moment uncertain.

Also, does this time lag vary with different lenses?

Cheers,

Rich Lahrson
tripspud@wenet.net

From: "auyeung" auyeungsf@hotmail.com
Newsgroups: rec.photo.equipment.35mm
Subject: Minolta's New focus system
Date: Fri, 5 Nov 1999

I read from the Minolta Mail list that Minolta has patented a new focusing system. It includes something like the image stabilizer system, great news to all Minolta users.

You can take a look on the patent by the following URL

http://www.patents.ibm.com/details?pn=US05973856__

From: Godfrey DiGiorgi ramarren@apple.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Auto Focus Technology
Date: Wed, 03 Nov 1999

Take a look at "Camera Technology: The Dark Side of the Lens" by Norman Goldberg. Excellent, well written description of many of the technologies which make up today's cameras.

Godfrey

Carina Rodriguez wrote:

> Hello,
>
> Surely most of us would agree that AF has been one of the landmarks in
> history of photo equipment. I could not find enough techical details
> on technology itself, and I would like to know, how does the logic
> inside camera works, particulary about one detail : if I focus on an
> object at some distance, and
> then move closer (or step back) the AF mechanism will (mostly!) move
> in the right direction of focusing (and focus in one step).
> Could you give me some references/links to read about.
> All comments appreciated.
>
> Regards,
> Carina

From Nikon Mailing List:
Date: Sun, 7 Nov 1999
From: Stanley McManus stanshooter@yahoo.com
Subject: [NIKON] 400,mm F/5.6 autofocus lenses for Nikons

Once again I ask, what are we to do for a 400mm f/5.6 autofocus lens for our Nikons? With Tokina dropping out of that line, the only other competitor with a good reputation is Sigma.

Or is Tokina anticipating the new 400mm F/5.6 AF-S lense and getting out while the getting is good?

rec.photo.equipment.35mm
From: Animus@webtv.net (Mikal Fisher)
[1] Re: Leica M and Popular Photography Testing
Date: Sun Dec 19 1999

I've used Leica M and high end Nikons for years. At first I thought the M images were slightly. Later I decided the reason for this was not superior glass but more precise focusing. When I began using an F4 with manual lenses and a focus assist light, my Nikon images seemed as good as the M cameras'. I do lots of low light stuff, and I just wasn't focusing as well with the SLR. MF

rec.photo.equipment.35mm
From: John Halliwell john@photopia.demon.co.uk [1] Re: Manual vs AF
Date: Thu Jan 13 2000

Richard Cochran rcochran@netcom2.netcom.com writes

>No.  It is still using the AF sensors to decide if the image is in
>focus, and is therefore limited to their precision.  The AF sensors
>may be more precise than your eyes sometimes.  The precision of the AF
>sensors is probably more consistent than the precision of your eyes.
>(If you're tired, drunk, or hung over, your eyes will not do well.)
>But carefully looking at a good focusing aid with good eyes is almost
>certainly more accurate than the AF sensors.

The problem with AF sensors in manual focus mode is exactly this. The sensor usually covers an area of frame, within this frame there may be different focus points. Which particular focus point (within each AF sensor) the camera decides is to focus on (or indicate as 'correct' focus), depends on the subject and the AF system, in other words it's unpredictable. With a split image focus aid, you choose the exact part of the image you want in focus.

An easy way to improve the paper performance of an AF system is to reduce the accuracy of it (increases focus speed and reduces 'hunting'). I'm not suggesting anybody does this, but with the current levels of competition on very cheap AF SLR's, it's something to think about.

--
John
Preston, Lancs, UK.

From: rdd5tk@aol.com (RDD5TK)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Manual vs AF
Date: 15 Jan 2000

My experiences are just the opposite of yours! I recently bought an FM2N for a backup to an N90s. The N90s viewfinder is much brighter and easier to focus any lens, AF or manual, at least with the screen that came on the FM2N. I shoot a lot of macro and was really surprised by the difference between the two camera viewfinders. Although the N90s doesn't have the split image, I just focus for maximum sharpness. Also, I use the DG2 magnification attachment, indespensible for absolute maximum sharpness when focusing.

From: Anders Svensson Anders.-.Eivor.Svensson@swipnet.se
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Manual vs AF
Date: Fri, 14 Jan 2000

....

> > It's not only the screen of an AF camera that's different.  The AF
> > camera diverts a significant portion of its light to the AF sensors
> > which are below/behind the mirror.  This leaves less light to reach
> > the viewing screen.  If you could put the exact same screen in both a
> > MF camera and an AF camera, the AF camera's viewfinder would be dimmer
> > than the MF camera's.
> >
> > Also, remember that if you change the viewing screen significantly, it
> > may affect the light meter's compensation.
> >
> > > Otherwise I will buy a FM2n and later a N70.
> > > (I may not have money to buy a N90s then).
> >
> > This sounds like a reasonable choice.  The FM2n is nearly the opposite
> > of the N90/N70.  That is, it has no automation whatsoever, but lots of
> > capability, and extremely straightforward and easy control of all the
> > functions.  The two would be complementary to each other, each being
> > well suited to different types of shooting situations.
> >
> > --Rich

I think this is the essence of the AF vs MAnual dilemma. My solution to that is to have a manual camera side by side with a AF one, and I think these cameras fulfill two different, but related purposes.

The AF camera is great for P&S; photography (and sports photography is very demanding P&S; work :-). The fastest subjects I personally go after is my son and his friends playing soccer (thats real football for us), but I would say that even a pretty lame AF camera like the Nikon F60 is a boon when it comes to shooting at fast moving game.

For more "contemplative" photography, the split image screen and the manual focus of a Nikkormat works quite well - at least for me.

--
Anders Svensson
Anders.-.Eivor.Svensson@swipnet.se

From: henrytaber@aol.com (HenryTaber)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Manual vs AF
Date: 14 Jan 2000

After using my autofocus cameras (Canon EOS) a couple years I started to notice a difference in sharpess between similar shots. Not until I got my darkroom built and developed a few of my own did I realize it was focusing that was making the difference.

I have started using only the center focus sensor lately and have noticed an improvement in focusing accuracy. What clued me here is that my 630's (only one sensor) prints overall seemed sharper than either my Rebel G or A2. Not always but in a rough average sort of way. It could also be that because the 630 has a tad bit more trouble finding focus I concentrate more on the focusing. But using only one sensor on the Rebel and A2 do the same thing and only takes a second longer to focus/recompose.

I have decided to get an eyepiece magnifier for my tripod shots where autofocusing is kinda unnecessary anyway.

I'm not knocking autofocus, it's essential for failing eyesight old codgers like me. I just now realize it ain't perfect!

Henry

From Nikon Mailing List:
Date: Wed, 24 Nov 1999
From: Ulrich.Bartling@gmd.de
Subject: [NIKON] How to take a perfect picture of your carpet

Often times, simple tasks have simple solutions. But are those simple solutions satisfying? Not always.

So why not find a complicated solution to a simple problem? For example, imagine you would like to take a picture of your carpet. So simple a task that you better hide your true intentions. Let me tell you how I managed to perform that.

First, I put a table tennis ball on the carpet and placed a cat next to it. I lay down on my belly holding my F90x+flash firmly in my hands focussing on the tt ball.

   Cat was ready to attack the ball, I was ready to press the release button.
   At time T cat attacks - I pressed the button.
   At T+0.1sec cat's front legs appeared in the viewfinder - F90x fired first preflash.
   At T+0.2sec cat hit tt ball -  F90x fired second preflash.
   At T+0.3sec tt disappeared from viewfinder - F90x fired third preflash.
   At T+0.5sec only the tip of the cat's tail was visible in the viewfinder.
   F90x pretended to carefully compute all necessary data but really wanted to
   wait for the last piece of tail to disappear.
   At T+1sec F90x fired and took a picture of the carpet.
   In order to perfectly hide my true intentions I set my F90x drive to H.
   F90x sent out another preflash ...... and yet another ....
   In the end I have had two pictures of the carpet.

To the best of my knowledge, this will only work with nearly exhausted batteries in the flash unit. When I finally had changed the batteries, the cat was almost fallen asleep and my wife questioned my mental ........ oh forget it.

**************************************************************************
  /\___/\   Ulrich Bartling
 /       \  c/o GMD - Forschungszentrum Informationstechnik GmbH
 | *   * |  German National Research Center for Information Technology
 \   ^   /  Schloss Birlinghoven, P.O.Box 1316, D-53754 St.Augustin
  \_~^~_/   Email: ulrich.bartling@gmd.de       Tel.: + 2241 14-2466
**************************************************************************

From Nikon Mailing List:
Date: Fri, 03 Dec 1999
From: Jonathan Castner jonathan@jonathancastner.com
Subject: [NIKON] Re: AF for birds in flight

Frankly I know a bunch of bird photographers who went from manually focusing to AF and then back to manual because the AF systems can't keep the all critical eye in focus when the bird is flying. AF will find the beak, head, wing but not the tiny eye and when you are using a 600mm wide open, that tiny depth of field will not compensate for deviations in focus. If the eye is not sharp, the image isn't good.

Jonathan Castner -Photojournalist
Denver, Colorado
Online folio at: http://www.jonathancastner.com

From Nikon Mailing List:
Date: Sun, 5 Dec 1999
From: "bradley hanson" bradley.hanson@home.com
Subject: Re: [NIKON] Auto vs. Manual focus

Nick-

Thanks for posting that link. I found the page, and several subsequent links, fascinating, this one in particular:

http://photo.net//neighbor/view-one.tcl?neighbor_to_neighbor_id=59340

I had some problems last night with the wedding I shot. Actually, everything was cool until the reception, then "mood lighting" killed the AF on my F5s, or at least, crippled it somewhat. I switched to manual focus but the stock focussing screen isn't quite as bright as my old Nikon manual focus or Contax stuff. Even though the lens was an 85 f1.4 and very bright, light was very low and focussing was difficult. Would it have been easier with an old MF body and lens? I don't know. It *was* nearly impossible to focus manually with the low light. With the AF, it would hunt like crazy unless I could find a white shirt with black near it.

I always use manual focus in the studio, of course. No need for AF in such tight quarters. I just noticed a few days ago how much sharper my portraits were, possibly due to the tripod use, but also, perhaps due to the fact that I spent time making sure focus was correct (and the F5 uses a focus aid system similar to the Contax RX, with the red directional arrows and green dot for "correct" focus) rather than using one of the five AF sensors. On a recent portrait session with Kodak EV100s, I could CLEARLY see a woman's pores and blonde mustache. Can I complain that something is too sharp? I am!

- -Bradley

From Nikon Mailing List:
Date: Wed, 15 Dec 1999
From: Pat Neave patneave@lucent.com
Subject: [NIKON] AF and flash

Hi,

I have just bought a SB22s for my F(N)90 and noticed that whenever the flash is attached and switched on the AF changes from wide area to spot focusing. I can find nothing in the manual about this. I am just curious as to why this is.

Pat

From Nikon Mailing List:
Subject: Re: Low Light Focusing - F4 vs F100, F5
From: John Albino jalbino@jwalbino.com
Date: Tue, 28 Dec 1999

Steve wrote:

>light focusing ability. Sometimes my F4 has difficulty "locking on" to the
>subject. Are the F100 and F5 an improvement in this respect in low level
>existing light?

My F100 focuses quickly and accurately in _much_ lower light than my F4. So, yes, the F100 AF system is superior to the F4 in low light.

However, I rarely use AF in low light. I much prefer manual focus, because I can more accurately refine the exact point I want in focus. I usually use my F4 in manual mode as my available light camera, while the F100 has the SB-28 on it. With flash, AF, or even zone focusing, is enough, because at f8 or smaller I've got plenty of depth of field. But with available light, I don't want to rely on an AF spot being exactly over, and only over, my focus point.

And if it's so dark that neither manual focus or autofocus works well, and I'm using flash, I zone focus with at least a 35mm (or shorter) lens.

--
John Albino
mailto:jalbino@jwalbino.com

From Nikon Mailing List:
Date: Tue, 18 Jan 2000
From: Rodrigo Gimenez rge@adinet.com.uy
Subject: Viewfinder light loss because of spotmetering

I have a question for cameras that most of us use as manual focus today, like the Nikon F4 and Nikon N8008s.

Anyone knows approximately how much light is lost in the viewfinder because of light going to AF sensors and spotmetering in some cameras? In the Nikon F3 small holes are needed for centerweighted metering, using 8% of the light. But I believe that spotmetering and AF use more light than the small holes of the F3, because they are different systems (some cameras use secondary mirrors).

Rodrigo Gimenez

From Nikon Mailing List:
Date: Fri, 28 Jan 2000
From: "Paul Ricci" pricci@tiac.net
Subject: [NIKON] System compatibility (was:F80, manual focus, switch to Canon nonsense!!!)

In my opinion Nikon has created a mess as far as true system compatibility is concerned.

1. n60 - no afs, mf, or 3dmbff compatibility

2. 80-400 VR - not supported on n90(s), n70, n60, and earlier af bodies, ...(are the other guys "IS lenses" functional with their early e-mount bodies?). And no AFS on a high end lens such as this? Oh well!

3. no af telconverters, except of course for afi/afs. and the mf converters provide no or limited metering with af bodies (F4 the exception).

4. n80 - no mf support - -Looking at the earlier AF generations-

5. No afi/afs support in n4004s, n6006, n8008s, n50, n60 - all were released after the F4 which can drive this type lens.

Yes, there is compatibility within the system, but it is no longer a cohesive system. The maddening part is that this appears to be a deliberate strategy. Crippling metering with mf lenses and no support for VR on recent AF bodies is ridiculous. Nikon set a standard when they introduced the AI-lens. Not only did they maintain compatibility with older bodies via the metering prong, they offered to upgrade older lenses to AI. How far our beloved Nikon has fallen from the standard they set!

By the way Nikon still produces mf lenses, and some are without an af equivalent. Are these not part of the system?

With regard to whether or not I or others would have been better off with canon or minolta or whatever other brand - I could care less. I shoot Nikon.

Best regards,

Paul Ricci

...

From Nikon MF Mailing List:
Date: Thu, 27 Jan 2000
From: Tenrec@aol.com
Subject: Planned Obsolescence

bart.mendelson@tebenet.nl writes:

Thanks everybody for your input on my question about the LCD-faillure on the F3. I just read that the F80 (N80 in the US) will be available soon but cannot be used with MF-lenses. Bad!

Canon and Minolta dropped their manual-focus customers outright. Nikon has stayed with us for a long time, but is gradually trying to wean us over to autofocus. They have been delaying the inevitable, and trying to make the shift as palatable and painless as possible, but I think they are trying to stay competitive.

The news about the F80 confirms this shift. The fact that the 28-70 f/2.8 and the 80-200 f/2.8 "Silent Wave" lenses WILL NOT AUTOFOCUS on older autofocus Nikon cameras was my first clue. Not only are they obsoleting the manual focus mount, they are even obsoleting the original motor-in-body philosophy and moving toward Canon's motor-in-lens design. They are doing it slowly, and gradually, but they are doing it.

Steve

[Ed. note: note how viewfinder coverage drops as you go down product line to consumer level AF...]
From NikonMF Mailing List:
Date: Sat, 22 Jan 2000
From: Rick Housh rick@housh.nu
Subject: Re: F3

....

Yes, Bart. I know what you mean. I wear trifocals, and even with the F3HP the magnification of the middle section I need to use to focus on the one-meter virtual distance of the screen effectively kills the high eyepoint advantage for me. Then, if you also want the 100% view, even with high eyepoint finders only the top "pro" models, F3, F4, F5, will do that. Of the other high eyepoint models the F100 is 96%, the F90, N70/F70 and N6000/F601/F601M are about 92% and the F60 and F50 are 90%.

- Rick Housh -

[Ed. note: AF and astrophotography?]
From: Tony Spadaro tspadaro@my-deja.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Lens barrel 'slop' and sharpness...
Date: Thu, 25 Nov 1999

  Paul Chefurka chefurka@sympatico.ca wrote:
> On Wed, 24 Nov 1999 "PSsquare"
> pschmitt@stny.lrun.com wrote: 
> >Michael A. Covington wrote 
> >>I suspect it is OK when the AF motor is actually operating, but might not
> >be
> >>OK for a long time exposure, especially one in which the camera is  moving
> >>during the exposure (as it is in astrophotography, when a telescope tracks
> >>the earth's rotation to stay aimed at the same star for an hour or  so).
> >Any
> >>actual experiences?
> >>
> >>
> >>
> >What does AF have to do with how the image falls on the film plane? The AF 
> >does not operate on the film plane.
> >
> The supposition works like this:
>
> 1.  AF lenses are built "looser" than MF lenses - i.e. the lens group
> has less coupling to the outer lens barrel (e.g. no helicoid or
> viscous lubricant) in order for the AF motor to be as small as
> possible.
>
> 2. This increased tolerance results in some wobble in the lens group
> relative to the outer barrel, and so also relative to the film plane.
>
> 3.  When the AF motor is engaged, it loads the lens structure,
> providing pressure will keep it stabilized relative to the lens
> barrel.
>
> 4. When this pressure is removed the glass is free to wobble about  
> just a bit relative to the film plane (which is fixed in relation to
> the lens barrel)
>
> 5.  If the camera is on a moving platform like a motorized astro
> mount, the changing position of the whole assembly will allow the lens
> group to gradually drift in the lens barrel if the AF is disengaged
> (as it is in astrophotography).
>
> 6.  This drift may cause a slight but gradual change in the optical
> axis of the lens, causing some increase in aberrations at the film
> plane.
>
> Whether this in fact happens, or whether it makes any practical
> difference to the image, I have no idea.  But it's one more little
> thing to keep you AF guys awake at night, and that's good enough for
> me ;-)
>
> Paul Chefurka

Date: Sun, 23 Jan 2000
From: ewindell@psci.net (Gene Windell)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Old camera vs new camera

>>Hello Folks. I have a Canon A1 which I think is pretty good. I have been
>>thinking about getting a new Auto Focus camera. What are some benefits
>>of the newer cameras compared to my A1 for instance.

If you've never used an AF camera for real-world (outside a camera store) picture taking, you will be in for quite a shock.

AF cameras are computerized picture taking machines. Like any computer, it doesn't think and requires user inputs to tell it what to do. Usually, providing the user inputs require more thought and effort than doing the same job manually with your Canon A1.

The A1 uses primarily knobs and levers for operating the camera. A computerized camera uses primarily push buttons and wheels for controlling user inputs. There may be no aperture ring on the lens, or depth of field scale engraved on the lens. There is usually an LCD panel, which serves as a computer monitor to display the status and mode of the computer. The display panel is difficult to read in dim lighting, and the information may be in the form of cryptic icons. Consequently, you'll need to keep the inch-thick instruction manual with you all the time - in case you accidentially get the camera into some "mode" you don't want and can't figure out how to get out of. To avoid carrying the instruction manual around with them all the time, many computerized camera owners simply use 1 or 2 familiar modes, and let the whiz-bang capabilities of the camera go unused.

With a manual focusing camera such as yours, focusing the lens and releasing the shutter are to different and totally unrelated functions. But with an AF camera, you focus the lens by pressing the shutter button. When you press the shutter button, the lens will attempt to focus before the shutter is released. In bright sunlight, the lens focuses instantly and there is no noticeable delay. But in dim lighting, high contrast lighting, or with subjects that lack contrast - the AF lens will "hunt" back and forth trying to achieve focus. Or it may lock focus onto something you don't want. In difficult lighting situations, the lens may not be able to focus at all - in which case you have to switch to manual focus mode. But the user is normally inclined to "give it a chance" to attempt focusing, before admitting that it isn't going to work. The time you have wasted in "giving it a chance" to focus may result in loss of the picture opportunity.

The focusing screen in AF cameras is not as contrasty as that in a manual focus camera, and there are no focusing aids such as the split image and microprism collar. Consequently, when you are forced to use the AF camera in manual focus mode, it is more difficult to focus accurately than if it was a manual focus camera. In short, AF only works reliably in ideal lighting conditions - when focusing a manual camera is also no problem. But in difficult lighting conditions, when some focusing assistance may be helpful with a manual camera - the AF camera may not be able to achieve sharp focus at all - even in manual focusing mode. So unless you have serious vision problems, or you got your left arm shot off in the war, or you plan to specialize in shooting fast-action sports - AF is essentially a waste of time and money. It will do nothing to make your pictures look more impressive.

AF camera users are quick to apologize for the limitations of the technology, and offer "work-arounds." They'll say "well, you had the camera in the wrong mode," or "you pushed the wrong button" or you pushed the buttons in the wrong sequence" and that sort of thing. But the bottom line is that autofocusing cameras provide the solution to a problem that never existed, and answers a question that nobody asked.

In this newsgroup, the owner's of computerized cameras often ask questions seeking advice on how to operate their cameras. These questions always address the same issue: "how can I make my camera stop doing things I don't want it to?" Curiously, owners of non-computerized cameras such as your Canon A1 never have this problem. Using a computerized camera simply imposes a computer inbetween the photographer and the picture taking process, attempting to substitute automation in the place of technique.

A computerized, autofocusing camera is much like a Nintendo Gameboy with a lens grafted onto it. If you win the game, you get a sharply focused and well exposed mundane snapshot. If you lose the game, the picture will be poorly focused and/or badly exposed. So if you enjoy playing video games more than working a camera, then a computerized camera may be just what you want.

The only way you are going to pictures that look more arresting, dramatic, or inspiring than what you're getting now is to improve your techniques. It is all to do with selection and arrangement of the subject matter, composition, and lighting. The camera has nothing to do with any of this, and adding a computer to the mix certainly isn't going to help. I suggest you get and study some books on lighting and composition, with lighting given the higher priority. Lighting is usually the last thing that photographers learn, when actually it is the most important. If you don't understand lighting, you're really not qualified to buy film.

Now, if you simply have some surplus cash and want to buy a new camera - there's nothing wrong with that. If you want to get a camera that will give you the impression that it is a better camera than the Canon A1 you've already got, take a look at the Contax RX.

Gene Windell

Date: Sun, 23 Jan 2000
From: "Woodard R. Springstube" springst@jump.net
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Older camera VS new technology

For what it's worth, I just bought a Nikon FM2n, fully manual. I also have a Nikon N70. I like both of them. They each have unique strengths and weaknesses, advantages and disadvantages. I expect that the FM2n will work more seamlessly with bellows, and I think that it would be better for attachment to a telescope for astrophotography. It also has other advantages for me for some types of pictures. It does have DOF and I can do a timed night shot without running down a pair of $8 apiece batteries. On the other hand, for use with a flash for events, then the N70 will be my choice (with an SB27). This list is not exhaustive, of course. I look forward to spending the next few months finding out what works best for each type of picture I take. Happy shooting,
Woodard Springstube

Date: 25 Jan 2000
From: kartboad@pc.highway.ne.jp (Hiroaki YOSHIFUJI)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF cameras with split-image focusing screen (was: fm2n)

...

  | > great availability of focusing screens compared to the F5 and F100,
  | > especially split-image screens; faster flash sync than my F2/F3; and
  | > spotmeter).

I use my F5 and F4 on manual focus except [when] I need AF tracking for fast moving subject[s] like motorsports and running children.

But I don't like split-image screen, so I changed to mat with grid screen for my FE, FM2, F3 and Contax 167MT. I can focus anywhere on mat after composition.

With split-image screen, you can focus only at center and [your view is] look obstructive.

  | This has me wondering: does anyone use an AF camera that allows for
  | interchangeable focus screens (like the F4s or F5) with a split-image screen
  | (say, a Nikon A or K)? Contax AF camera AX comes with split-image  screen.

Hiroaki YOSHIFUJI

From Nikon Mailing List:
Date: Mon, 7 Feb 2000
From: Tyler Harris TylerH@tetratec.com
Subject: Re: [NIKON] Where are the new primes???

Adriel C wrote

>the whole point of the 50/1.8 is cheap and small... If Nikon made the 1.8
>a "D" lens then it'd cost just as much as the 1.4

I don't see how this should increase the price by any more than $10.

Adriel C wrote

>why use a 105/2.5 when there's a 105/2D and has DC control?  why not just get the DC version?

Because AFD 105/2.5 might cost 1/3 of 105/2 DC.

Here is why I think this

AFD 20/2.8 = $440 while MF 20/2.8 = $640
AFD 24/2.8 = $290 while MF 24/2.8 = $370(gray)
AFD 85/1.4 = $950 while MF 85/1.4 = $800(gray)

Following this logic one would expect an AFD version of the 105/2.5 to be cheaper than its MF counterpart. The 105/2 DC costs $850 while a new MF 105/2.5 costs only $380. If Nikon could knock 30% off the price of the MF105/2.5 we could have an AFD for ONE-THIRD the cost of the 105/2 DC. Plus the 105/2.5 has a 52mm filter instead of the 72mm(?) of the DC.

I want a 105 (not 85 or 135) so my only choices now are Micro ($$), DC($$$) or, MF.

Tyler Harris

From Nikon Mailing List:
Date: Mon, 07 Feb 2000
From: "Adriel C" shire07@hotmail.com
Subject: Re: [NIKON] Where are the new primes???

All valid points...

and I'm caught speechless at 6:20am.

Great explaination for a possible 105/2.5 to end up going for a third of the DC version. However, much as it seems reasonable, I HIGHLY doubt that Nikon will come out with one soon, given the (even) more severe, important gaps in their line... namely updated versions of the 35/1.4, 180/2.8, 300/4, and 400/5.6. Basically, why put out another 105 (there're 8 AF lenses that I can think of that include the 105mm fov) when there's a missing 400mm (only 1 AF version - - the AF-S 2.8)

what's interesting is this:
there're the 400 F/2.8 F/3.5 and F/5.6 in MF, but AF only has the AF-S 2.8. ...

regards,
AD

From NikonMF Mailing List:
Date: Mon, 7 Feb 2000
From: "dr. Moso Tamas" moso-t@prolan.hu
Subject: Re: F3 shutter lag?

You wrote:

>Does anyone know what the shutter time of the F3 compared to the newer
>F100 or F5 in millisecond or whatever the times are measured in?

A modern AF body has 100-200ms shutter lag in MF mode!
German FOTO MAGAZIN usually test this. Eg. in 12/99
Cannon EOS5 (A2) 155ms, Pentax MZ3 181ms, F90x 276ms(!)

It can be detected and annoying. (At least for me)
I have measured my F801s (N8008s) shutter lag. It is 84ms without AF. (This is the delay from the electronic remote release to flash synchrony signal, measured by oscilloscope.)

dr. Moso Tamas

From Nikon MF Mailing List:
Date: Tue, 8 Feb 2000
From: Dave Schneider dschneider@arjaynet.com
Subject: Mirror Lock Up Body

I am looking to add a body with a true mirror lock-up. I have an N90s and and FG but as I am doing more macro work I regret the mirror lock-up I had years ago. I was contemplating shopping for a well used F3 but then came across another idea. Would a Nikkormat FT3 be a good choice? I need a body that will function with AI and AF lenses. Other than mirror lock up and a good shutter I don't need much. My concern with the Nikkormat relates more to reliability and serviceability. If I have problems with it are parts still available for the FT3. I will spend $600-700 if I have to for the F3 but if I can get a good FT3 for $200 I would consider it. Comments appreciated.

From Nikon Mailing List:
Date: Mon, 7 Feb 2000
From: "Tyler Harris" tharris242@email.msn.com
Subject: [NIKON] Where are the new primes???

To the best of my knowledge these are the last 9 lenses Nikon has announced (in no particular order). Notice that there is only one prime (that has a somewhat limited market). [Ed. note: a PC or shift lens prime]

70-300
28-105
17-35/2.8
28-70/2.8
80-200/2.8
75-240
28-80
80-400/VR
85/PC

Where are these primes?

50/1.8 AF-D   
35/1.4 AF-D
105/2.5 AF-D
300/4D(AFS)
400/5.6 AF-D

I am impatiently awaiting AT LEAST two of the above.

When is the next chance for Nikon to announce some new stuff?

Tyler Harris

From Hasselblad Mailing List:
Date: Sun, 16 Jan 2000
From: BLADHASS@aol.com
To: hasselblad@kelvin.net
Subject: Re: Thoughts on Leica

The reason I was looking for the SLR Leica is that I need longer lens in my work, I have thought about the M6 and even the Contax camera both versions.

I really like all the info I have been getting from this group. I know that the group in whole can probable solve any photographic problem put to it.

I have started rethinking my needs even more. I have always wanted a Leica even before I knew what a Hasselblad was. I remember seeing adds for Leica while in high school, and thinking that's the camera I want. 20 years later and I still want a Leica. I have been shooting Nikon gear, and have the FM2n and a N90s. But I have found the auto focus on the N90s slow and seem to use it on manual focus. I could try the F100 or even F5. But last night I photographed candids at a big company party. My other employee helped out with a F5 and the 28-70 F2.8 silent wave lens, with both used the SB26, and we both had to go with manual focus. Very tough to get those cameras to focus when all are wearing black, black, and black. So I though I'm going to buy a Leica with that nice bright finder, and spend more money then on my Hasselblad gear.

Thanks for the input, hope to hear more thoughts.

Peter Peterson
Seattle, WA

Date: 18 Jan 2000
From: guy@nospam.com ()
Newsgroups: rec.photo.technique.nature
Subject: Re: Micro-Nikkors 105 mm. AF or non-AF?... difference ?

Jack pretty much summed it up. One thing I would add is a rather subjective one - the "feel" of the lens. The MF feels much smoother and tougher. The AF focus ring feels looser (obviously as it needs to be rotated by the camera motor) and is harder to focus manually. Note harder, not hard. I use my AF manually most of the time, but I miss the feel of my old AIS. They are both optically excellent - great resolution and color and very flat field.

Guy

....

Date: Fri Feb 11 2000
rec.photo.equipment.35mm
From: g.a.woodell@larc.nasa.gov (Glenn Woodell)
[1] Re: experience in fotographing animals with Manual focus

>Tell me your experience in photographing animals with manualfocus
>cameras. What equipment do you use?

In some situations MF can be better while in others, AF can be better. AF can waste a lot of time seeking if you have a small subject against a low-contrast background like water or sky. But for some moving subjects AF is definitely a plus.

I use a Nikon F3 with a Tamron 300/2.8 and Nikon TC-301 2X teleconverter usually mounted on a monopod.

[Ed. note: AF problems with side motion surprises!]
Date: Sat Feb 12 2000
rec.photo.equipment.35mm
From: "abyssal" abyssal@gte.net
[1] Re: experience in fotographing animals with Manual focus

I agree with Mr Woodell. For fast moving high contrast subjects, af if fabulous. However, be wary that when using predictive af, sometimes hunting will occur such as when shoot flying birds. Predictive af works great with subjects that are coming and going, but side shots will almost always leave you searching for focus. If you use single shot af, then the focus takes only milliseconds and once locked on, never changes unless you want it to. For low contrast subjects or side shoting moving subjects, manual focus is the way to go. I currently use a 1000mm f/10 mirror in AV mode at f/1.0 on a EOS 630 or 620 body and monopod. Sometimes I use a Series 1 300mm f4.5 freehand.

From Nikon Mailing List:
Date: Sat, 19 Feb 2000
From: Phil McCrohan fatboy@iaccess.com.au
Subject: Re: [NIKON] Found F5 Viewfinder Blackout Time

The following site has lag times etc. for some major electronic cameras. It reports the F5 as 20-21ms with the mirror locked up and in manual mode, and 40ms for normal automatic operation. The Canon EOS-1N is 55ms (manual) and 191ms (automatic); fairly slow. Hopefully the EOS-1v will be quicker.

http://www.fone.net/~rfrankd/CameraCompatibility6/CameraCompatibility6.htm

Regards Phil.

...

Date: Sun, 27 Feb 2000
From: Blackcatzeke@aol.com
To: rmonagha@post.cis.smu.edu
Subject: af vs mf

Hi Robert,

You have and excellent site. I used the nikon f3 and some newer nikkor afs (24-120af), within one week of practically no use the lens barrels even when fully retracted had a wobble to which nikontech reps said was normal in such a lens design.

Another scenerio, put a nikon 80-200f2.8ed with a nikon 1.6 af converter and coupled with an 8008 body..... and you can't focus to infinity unless you switch to mf and manually focus! They fooled me twice.

I switched to a pure mechanical system and after reading your site made me feel even better!

Also had two different friends drop their camera and lens into water, by accident, for an instant of time..the Canon EOS and Canon zoom are BER, the Minolta with the Tokina 28-70atxpro working after an hour of drying out....could it be the metal barrel lenses are milled to tighter tolerances than polycarbonates, thereby making a better seal?

Take care

George Kmetz

Date: Wed, 16 Feb 2000
From: "Stef Bras" stef@hi.nl
Newsgroups: rec.photo.equipment.35mm
Subject: Re: why does AF interfere with clarity?

Compared a X700 (Minolta) with a 2.8 28 mm with a Nikon F70, 2.8-4 28-105 mm.

The image in the Minolta is definitely clearer. Manual focusing with the minolta is easier. (Mainly because of the microprism) than manual on the F70. The Minolta screen is optimised for manual focusing the Nikon is not and the Nikon is darker because of the mirror is transparent.

AF beats me in speed all the time.

But given the time. (Prefocussing with moving objects) Manual focusing beats AF.

Test.

Do a manual focus without the AF aids, without the focusing aids (of other camera's).

If I manual focus my F70, it almost always gives a correct focus signal when I turn it on. So I do at least as well. (Although maybe AF has a larger range for showing something is in focus than it uses to set the focus, I can't check that).

So I am happy with my AF, wanted to have one for years. But know that it can be beaten.

What's limited with AF ?

	
- The AF system works only where the sensors are.
- The AF system can not focus on color alone it needs contrast.
  (Eyes can use color as well (or colour depending where you live)).
- Prefocusing with AF is more of a hassle.
- AF has a limited resolution. (But so have your eyes).

stef ten bras

.....

[Ed.note: good correlation to 12% improvement for AF lenses focused manually reported by Pop Photo Tests above...]
From: "bb" dontlike@spam.com
Date: Wed, 16 Feb 2000
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Len Quality - is one really much better than the other?

Thanks to all who responded.

I learned something. Both from the posts that said ignore Photodo AND the ones that said check with Photodo !!!

The post pointing out various AF weaknesses was especially interesting because in my know-nothing-ness I tried some manual focus shots of the resolution targets and found an average of 15% increase in resolution. However, I'm still using AF routinely so I guess that shows how serious I am about maximum sharpness...

Anyway, a week has passed and I seem to have accumulated about 100 photos. Most are pretty bad (and it wasn't the equipment) but some are surprisingly good.

Kind of like golf. That one good swing makes up for all those duffed shots.

So, however belatedly, another photographer has been born.

Cheers,
Byron

From: llutton@aol.com (LLutton)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Older camera VS new technology
Date: 22 Jan 2000

>Hello Folks. I have a Canon A1 which I think is pretty good. I have been
>thinking about getting a new Auto Focus camera. What are some benefits of
>the newer cameras compared to my A1 for instance.

I have a Canon F1N and an AE1. Lately, I bought an EOS camera. I was shooting a wedding and was having a difficult time getting the camera to focus and shoot at the reception. I discovered the camera wouldn't auto-focus in the darkness of the dance floor. I had to take it out of Auto focus. Score another one for the older "low tech" cameras.

Lynn Lutton

llutton@aol.com

Date: 04 Jan 2000
From: ishanon101@aol.com (Ishanon101)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: discontinuing the good things.

It's really interesting - After going to the new Nikons, including the F5, I switched to Leica ranngefinders with fixed lenses, but still kept my Nikon F4s and a few lenses. (The Nikon F4s provides me with all the modern-day slr features I want, yet has a user interface that's closer to the traditional manual cameras). I realized that pictures I had taken 20 years ago with totally manual cameras were superb to what I was producing with the modern wiz-bang equipment. I also found that using modern equipment in manual mode was cumbersome and the AF lenses just didn't have the precise focus feel. In viewing this board daily, I've noticed that a lot of other serious photographers have come to a similar realization. My passion for photography has increased dramatically since I've gone back to manual cameras. Not only that, but I don't worry about a complete shut-down of my camera because of a lost bit or drained batteries, and my shoulder has healed now that my camera bag is a lot lighter and smaller. And the best part is that after pushing little bottons and reading lcd's on my cellphone and computer all day, its a pleasure to handle a well-built mechanical non-electronic piece of gear.

Ilan Shanon

From: Dave
Date: Mon, 03 Jan 2000
Newsgroups: rec.photo.equipment.aps,rec.photo.equipment.35mm
Subject: Re: discussions on Camera formats

Good statements about planned camera model obsolesence... I have both the Olympus XA and the Yashica T4 Super. If I had to give up one, I'd give up the T4 even though I absolutely love it. The XA is, perhaps, not quite as sharp lens-wise, and it's certainly not as convenient to use as the T4, but I marvel at this little camera. The battery in it is eons old, and it keeps doing the job. I have no problem whatsoever with having to wind my film to each successive frame. I wish that camera makers (and computer and software makers for that matter) would get a clue and stop piling on the features in place of quality. One final thought about the T4, though. The T4 does seem to have a better lens than the XA. The T4 produces consistently sharper images... unless that pesky auto focus gets fooled. I'd sure love a complete manual override for it. It took awhile to remember to do a focus lock when I was taking a fairly closeup picture of (for instance) two people standing together with a deep background. (The T4 likes to focus on the wall between/behind the subjects for this situation. Easy to correct. Just gotta' remember to do it!)

ewindell@psci.net (Gene Windell) wrote:

>On Sun, 02 Jan 2000 10:32:15 -0500, Stephane Larochelle
>stephane_larochelle_ca@yahoo.ca wrote:
>>
>>Gene Windell wrote:
>>>
>>> So while the auto-everything, APS cameras offer the maximum in
>>> convenience - they take terrible looking pictures, even worse than
>>> their 110 and 126 format predecessors.
>>
>>Well, you had me interested in your comments until the above line.
>>The you lost all credibility. Saying that APS make worse picture than
>>110 is simply nonsense. As a person who used 3 different 110 cameras in
>>the past, and am presently on my second APS, your statement is simply
>>no true.
>
>If my math is correct, that is a total of 5 pocket cameras you have
>bought.  And I suspect there are some things about your current APS
>that you find objectionable - which will lead you to buy an even more
>sophisticated and expensive APS camera in hopes of overcoming those
>objections.  This is the type of consumer that the camera
>manufacturers love.
>
>If your first 110 camera had been one of the top quality models, such
>as the Canon 110ED or the Rollei A110, you would probably still be
>using it and could have avoided buying the 4 subsequent cameras.
>
>The best pocket camera I ever owned was an Olympus XA with the A11
>flash.  Out of several hundred rolls of film, I never had 1 single
>picture that was out of focus.  This is undoubtedly because the camera
>has an excellent rangefinder and a manually focusing lens.  The
>aperture preferred autoexposure system was quite accurate, and never
>failed even 1 single time to give me a satisfactorily printable
>negative.  The tiny A11 flash never 1 single time gave me a picture
>with "red-eye," even though it had no red-eye reduction feature.  Yet
>the Olympus XA is barely larger than a pack of cigarettes - smaller
>than any 126 Instamatic and only slightly larger than an APS camera.
>
>So why did the Olympus XA go out of production?  Same reason as all
>the others - market saturation.  The point was reached where everyone
>who wanted an Olympus XA already had one - and there was no reason to
>buy another.  In order to stay in the camera manufacturing business,
>Olympus had to convince consumers that manually focusing a camera was
>difficult - and that autofocusing would be more convenient and
>therefore make them happier.  Likewise, they had to convince consumers
>that manually winding the film was difficult, and that a "motor drive"
>was required.  Etc., etc, etc. Thus, the Stylus and Stylus Epic were
>born and the manufacturer stayed in business.  Yet the manually
>operated XA will consistently outperform the Stylus Epic or the
>Yashica T4 if excellent results on every shot is the criterion.
>
>Gadgetry such as autofocusing and "red-eye" reduction virtually
>guarantees brisk future sales, simply because these techologies can
>never be improved to the point where they work as well as advertised.
>But hope springs eternal, and the cash register keeps ringing as each
>new year offers "new and improved" models of cameras which are based
>on the same fraudulent concepts - that computerization results in
>improved picture quality.  Perhaps if my ballpoint pen was
>computerized I would be a better writer?  But then, who cares about my
>writing skills so long as my ballpoint pen can entertain me with
>whirring motors and flashing lights.
>
>What I'm suggesting is that consumer camera design was optimized and
>perfected about 15 or 20 years ago,  and the technological
>developments that have been introduced since then have done nothing to
>improve average picture quality - and serve no purpose other than to
>keep the factory smokestacks pumping.
>
>I speculate that the average photographer can get as many "keepers"
>from a roll of film by using a single-use, throw away 35mm camera as
>he can get by using a fully computerized APS (or 35mm) P & S camera.
>
>Gene Windell

Date: Wed, 05 Jan 2000
From: "Mac Breck" macbreck@timesnet.net
Newsgroups: rec.photo.equipment.35mm
Subject: Re: discontinuing the good things.

Radimus radimus@my-deja.com wrote

> Aesthetics aren't the only appeal to manual cameras.  Functionality is
> a major part of it too.  There are many things the new SLR's lack that
> are things we users of older cameras rely on.  For example, while you
> can turn of the AF feature, most AF SLR's are difficult to focus
> manually.  The viewfinders lack focus aids like ground glass and
> prisms.

...and the split image rangefinder !

> The focus rings on AF lenses are small and loose.  The lenses
> often lack DOF scales.  You are almost forced to use the AF to get by.
> On a manual SLR, one learns to preset the focus for shots you need to
> get quickly.  If your using a tight aperature you can zone focus.
> Loose focus rings and no DOF scales no longer allow this.  Even if you
> had a DOF scale, the loose focus ring wouldn't stay where you put it.

How about the lack of one-touch zooms? Most of the AF Zooms I've seen are two-ring zooms. Why can't Nikon build a nice, high (pro) quality, one touch, constant maximum f/stop zoom with color-coded DOF lines on it anymore? Is this beyond their abilities???

Also, you forgot about the dead area when turning the focusing ring before resistance is met and it actually starts moving the elements, and the gear/motor resistance which can cause you to overshoot where you wanted to focus. These two combine to make it a pain-in-the-ass to manually focus a 60mm f/2.8 AF Micro-Nikkor in the 3ft to Infinity range. (So, I sold mine and got a new 55 f/2.8 AIS Micro, PK-13, and had $25 left over. Love my 55!)

> Additionally, to say that modern cameras are a magnitude more capable
> than the old ones is pretty subjective.  What a camera might lack in
> features can often be made up for in skill.

Everybody always seems to want to downplay that, but it's true. In October I did follow-focus of a speed boat on the river, using my F2AS, 300 f/2.8 ED-IF AIS Nikkor, TC-301, Bogen tripod w/Super-Ball Head, and Elite II (ASA 100). The slide came out great.

> AF and AE have their
> place, but to someone who can evaluate focus and exposure by eye these
> capabilities are usually more of a hinderance.

Right, it gets in the way. Give me an actual shutter speed knob, manual focus ring on an AI/AIS (non-AF) Nikkor, f/stop ring on the lens, split-image rangefinder screen, and FM2/F2AS type viewfinder and I'm happy. That's all I really need.

> For example, AE slows
> me down because I have to shift the camera to a different mode or lock
> the AE on a different scene when the meter gets thrown off my a bright
> spot.  In a manual camera if I know what exposure the rest of the scene
> needs and already have the meter set for that I can ignore the meter
> and just take the picture.

The camera does what you tell it. Don't you love it? I do.

> > Were I a manual everything fanatic, I would buy Leica in a flash!
>
> I would like to buy a Leica too.  Feel free to send donations to the
> Radimus Leica Relief Fund.

LOL! Me too!

Mac

Date: Wed, 19 Jan 2000
Newsgroups: rec.photo.equipment.35mm
From: jerobins jerobinsje@yahoo.com
Subject: Re: Looking for comments about Nikon 4004?

"imajchaos" imajchaos@sprint.ca wrote:

> I'm looking to get a Nikon 4004.  Any comments or suggestions?

As long as you understand what you are getting, it is a decent camera. I have a 4004s and love it. It will not meter with old manual focus lenses. The AF is "slow". My wife has an N70, so we share AF lenses. No DOF preview or mirror lockup, or remote shutter release. Does have a timer which I use in leiu of the latter. Max speed 1/2000. Remember, it's a light box! I got one in great condition used for $125. I've had the opportunity to take some really great shots. If you want more features at a good cost, find a 2020.

Have fun!
James

Date: Thu, 20 Jan 2000
From: "Dan Honemann" ddh@home.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Help choosing Manual SLR

....

> Third, autofocus.  Long before the FE2 was discontinued, Nikon
> realized that the success of their future profitability rested on
> autofocus technology.  Nikon had introduced autofocusing cameras in
> the same price range as the FE2, and they didn't want the FE2
> competing against their own autofocus cameras.

This is likely the reason, all right, and it's a real shame. Clearly, Nikon must know there is a market for manual focus bodies alongside AF bodies--hence the FM2N and F3HP. What boggles my mind is why they dropped the superior line (FE) in favor of the others? The F3HP does offer the right combination--i.e., autoexposure, but manual focus--but suffers from a slow shutter (top 1/2000) and flash synch (1/80)--and costs more than an F100.

....

Right--so why not capitalize on that and continue to market it in updated versions? That's what I don't get. But I'm sure you hit the nail on the head re. AF bodies. They can charge more $$$ for those and, since they have computer chips in them, know that they will grow obsolete much faster than MF bodies. That makes good business sense for Nikon, but bad news for the consumer.

I don't mean to rant on AF bodies. I think the F100 is a fine camera and may end up purchasing one myself. There _are_ times when AF and a fast motor drive are nice to have. On the other hand, there are many more times when I prefer the accuracy/control of manual operation--esp. focusing--and that is much more difficult on an AF body (for reasons you've aptly pointed out) than on the manual ones. And I'd buy a camera that was essentially a cross between an FE2 and an F100 with everything minus the AF in an instant. Give me the advanced metering, flash, winder, keep DOF and mirror lockup (well, actually, this is one essential feature that's missing from both bodies, so ADD that!), workable focusing screens and a truly useable viewfinder, and you can leave out the AF if necessary (but why would that be necessary? Just because some of the light has to be redirected to the AF sensors? Can't the engineers find a solution to this?).

[...]

> So all these reasons combined to result in the discontinuance of the
> FE2.  It was a much better camera than it was supposed to be, and it
> competed against too many other products that Nikon and the camera
> retailers wanted to sell.

Having learned their lesson with the FE2, Nikon made sure to "cripple" the F100 by excluding mirror lockup and interchangeable viewfinders / screens so as not to hurt sales of the F5. They probably didn't cripple it enough, though, as the F100 is, from what I hear, outselling the F5 quite a bit.

.....

Thanks again for a most informative post, Gene.

Dan

From Nikon Mailing List:
Date: Tue, 29 Feb 2000
From: Ernie winwon@concentric.net
Subject: [NIKON] Nikon's Current Quality

I have been shooting "snapshots" and a few nice photos since 1969. I have owned a Nikkormat/Nikon FTN, FM, EL, FE and F2 all of which worked flawlessly and never needed repair (except for the foam rubber). In 1996 I purchased a N90s which has been in the shop three times for underexposure and still doesn't work. Recently I purchased a F100 which indicated "end" after shooting only 5 frames (yes I changed the batteries)-maybe a fluke--the jury is still out on this model. Has anyone had similar experiences with the current "electronic" models compared to the older mechanical Nikons?

Ernie

From Nikon Mailing List:
Date: Tue, 29 Feb 2000
From: Jim MacKenzie photojim@yahoo.com
Subject: Re: [NIKON] Nikon's Current Quality

- --- Ernie winwon@concentric.net wrote:

> Has anyone had similar experiences with the current
> "electronic" models
> compared to the older mechanical Nikons?

No. The only problem I've had with either of my AF bodies (that wasn't caused by me :) ) was the case where my F601 would say that subjects were in focus when they clearly weren't. The problem has disappeared on its own. I suspect it was a dirty contact as it seemed to only happen with one lens (although this lens worked fine on my other AF body).

Electronic cameras tend to work perfectly longer than mechanical ones, but when they fail, they tend to fail catastrophically.

With reasonable care I don't see why an AF body shouldn't last a long time, particularly if it's a well-built one such as the two you own. I'm not sure why you're having the troubles you are.

Jim
- ---
Photography on the North American prairies & plains:
http://www.onelist.com/community/PrairiePhoto

From Leica Mailing List:
Date: Tue, 29 Feb 2000
From: "Dan S" dstate1@hotmail.com
Subject: Re: [Leica] Leica vs. Contax wars

If only it could be so! I still think a manual focus Contax at about the same price as the current autofocus offerings would be a dream camera. As it is the auto focus problems with the camera along with a reputation for electrical glitches has kept many pro's and otherwise from indulging. Too bad as the lenses really are superb. The 28mm is cosidered the best in the business

Dan States

>More to the point than Leica vs. Nikon is the question of Leica vs. Contax,
>namely the G2.  It's become apparent that the Japanese-made Zeiss optics
>are
>equal or better than many/most Leitz offerings.  Coupled with a better view
>finder,  a very good auto focus and much less money, Contax has to be the
>leader  among  35 mm rangefinders. Right??

Date: Tue, 11 Jan 2000
From: "Hunia, A." A.Hunia@dlg.agro.nl
To: "'rmonagha@mail.smu.edu'" rmonagha@post.cis.smu.edu
Subject: Autofocus, website & question

Dear Robert Monaghan,

I welcome your attempt at summarizing all flaws ans glitches in modern SLR's at http://www.smu.edu/~rmonagha/third/af.html. My compliments! I will not hesitate however to admit that sometimes I felt that the arguments were out of place. Moments where I wondered what exactly you were trying to prove. The overall argument seems to be that we, as camera-consumers, are not at all benefited by all the R&D; investments of the well-esteemed manufacturers in the last 15 years or so. Though I can back many of the arguments that you use, I am still naive enough to want a little more positive approach! I will give you some of my own arguments/AF-history and want to ask you a question.

To give an impression of my share of 'autofocus-blues':

1988: I bought my first own camera, the Nikon F-401/4004, with the old 35-70/3.3-4.5 zoomlens. Loved the design and interface! For years I had used the old Praktica MTL-camera's of my father, which were completely mechanical. After some missed opportunities in terms of exposure and/or focus I craved for something more automated. To my big surprise the 401did not have a depth-of-field control button (I used it all the time on the MTL's). I found out that some of the older lenses would fit, but then the meter wouldn't work! I wanted to push-develop some B&W; film, but had no means to influence exposure (only DX-setting and no exposure-correction).

--> Within a year I sold the F-401 to my brother!

1989: I bought the F-801/8008. Fine camera! All controls on the right place, all the functions that I needed (except perhaps spotmetering, which came with the s-*upgrade*, two years later ..and MLU, which I needed later). I have used this camera A LOT and in many respects it has proved to be a very reliable tool. BUT there was this slight problem that this camera has with its power supply. When the batteries cannot match the demand by the camera, it tends to 'lock-up'. This happens at unexpected moments and is not simple to overcome. Static electricity may play another role in this problem, according to popular believe. Anyway, this all I had to learn from the Internet and its rich source of user-experiences. I brought it in for repairs at the official dealer/distributor to look into this problem. Three times! All-in-all it has cost me appr. $350 (including the replacement of the central IC, twice, plus some additional probably unneccessary checks) and they never admitted it was a "known problem"!!!. Apart from this I found out in an early stage that the AF was practically worthless, so I used it 100% manually. Also my distrust of automatic exposure and a dated sense of 'sports' makes me use my cameras on manual exposure for 90% of the time.

1994: I bought an F-3 for reliability and never regretted that.

In 1998 I added an F-4, practically for the same reasons, in response to yet another lock-up of the 801... Fine camera as well, but its long-term reliability is still to be seen. Recently, I gave the F-801 to a good friend. The F-series cameras are accompanied by some 20-30 year old Nikkormats that are still going strong.

To conclude from my wanderings in camera-land (Nikon-county): having some of the new features (TTL-flash) and interfaces really was worth the trouble. Nikkormats were not cheap, back in the 70s, but then you had DOF-preview and mirror lock-up and all other basic controls in a basic SLR-model.

Now indeed, as your arguments state, these features are only to be found in the 'professional' models, with according price-tags. That is indeed ridiculous and my only option seems to be: buy second-hand! On the other hand, there still is room for improvement in the SLR-world and many of us would be willing to scetch out the ideal camera. It has not been build yet and regarding the current developments in 35mm, it never will.

Overall I am very satisfied with the route that Nikon has taken. Slowly they are updating their products, not all features are compatible between the different era's of F-camera making, but when it comes to fitting and taking pictures, the oldest lenses can be used on the newest camera (F-5 that is, with a minor adjustment). They still have my (rather) undivided attention!

My question concerns your remarks about the matte-glasses in AF-cameras and the 'ground-glass' in older models. My experience is that the viewfinders of the F-801 and the F-4 are always easier to focus, even *more precisely* than that of F-3 and Nikkormats. I was struck by this fact when compairing the images of a fashion-show that I shot: the percentage of sharp images was higher on the films taken with the F-801! Recently I fiddled around with my 420mm combination on tripod and again the AF-camera (F-4) handled easier and more precise. Could you please give me some more arguments to show me the advantages of 'ground-glass' viewfinders? Do you have examples where the opposite was shown? I'd really appreciate some comment, because I appear to have come to a conclusion contrary to yours! What are we looking at, here?

Thank you for your informative website, regards,

Albin Hunia (ecologist/GIS specialist)
The Netherlands

[Ed. note: I don't doubt the AF screens are brighter and easier to use, but the magazine tests and related user posts above show that focusing accuracy is higher on the higher contrast screens. I suggested trying to focus with the AF bodies on manual, in a room with dim light, on an object 8-10-12 feet away. Put a mark on the lens with pencil (easily removed) to show the focused distance on the lens. Set the lens to infinity. Now refocus on the object. Did you end up exactly on the same spot? No, huh? Put another mark at that point. Repeat this 20 or 30 times. Try a wide angle lens or normal lens or another zoom focus position. Repeat. Now you should have a feel for how inaccurate your focusing manually with an AF body really is. If you focused on the exact same point each time, you have a lot better eyes than I do ;-)]

[Ed. note: about those mfger incompatibility issues...]
From: "RainMeister" iori@attglobal.net
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Macro Lenses
Date: Thu, 20 Jan 2000

I just came across a thread in photo.com that discusses the lens incompatibilty problem. One poster specifically makes mention of autofocus inaccuracy with the EOS3 and Tamron 90/2.8 macro combination.

See http://photo.net/bboard/q-and-a-fetch-msg.tcl?msg_id=000jPe&topic;_id=photo%2 enet&topic;=

RainMeister iori@attglobal.net wrote

> It was a toss-up for me as well until a camera technician who works on both

> advised me to go with mfr brand on autofocus lenses for future
> compatibility. It seems he was right. The February issue of Pop Photo
> reports that older independent brand lenses may not autofocus on the EOS3.

> As I'm about to take the plunge for that camera body, I don't regret  going
> with the Canon even if it was $120 more at the time (I bought grey market).

Date: Sat, 25 Dec 1999
From: "Al Denelsbeck" denelsbeck@ipassonspam.net
Newsgroups: rec.photo.technique.nature
Subject: Re: use of auto focus?

Joseph Zorzin wrote

>I've just been reading the "Auto Focus Problems Page" at
>http://www.smu.edu/~rmonagha/third/af.html.
>
>The arguments on that page really blast auto focus.
>
>But are his arguments all exaggerated?
>
>I'm still struggling with whether to buy an older model manual
>camera or an upt o date auto camera with all the bells and
>whistles (like a Nikon N90s).
>
>That auto focus page implies that you lose in many ways with an
>auto focus system. You lose light because some is lost making
>the auto focus system work and if you just turn it off, manually
>focusing an AF lens isn't as convenient or accurate as the
>focusing of a manual lens.

Depends greatly on the camera. I had two manual Olympus bodies for years, using the split-image microprism for focusing, and suffered from the too frequent 'slightly off' once I'd seen my shots. Then I switched to a Canon Elan IIE , and found that even manual focusing was far easier and more accurate. I believe this was due to a far better focusing screen, and they do tend to be better on newer cameras, which also tend to be autofocus.

Manual focus on an AF lens is usually much easier - in fact, the focus ring sometimes turns with pratically no effort, even on the bigger lenses. This is due to making the focus system light enough to be driven with a tiny motor inside then lens, and driven quickly. Adjustments can be very fast, and frequently done with one finger.

Light loss is due to the usual method of auto-focus on an SLR, which is to make a portion of the mirror semi-transparent and put the focus sensors beneath. Again, depends on the camera, but I haven't noticed a significant difference. You'll suffer far worse, and noticeably, from a lens with a smaller max aperture, i.e. f5.6.

The problem with auto-focus is that a) it's not perfect, and may suffer from not being sensitive enough, and b) you rarely run into a situation where your subject is a nice flat plane. This means that while you're concentrating on the eyes of your subject, the AF might settle on the closer nose/beak/whatever, and with a minimal depth of field this ruins the shot. Or the AF area is too wide and can't decide on which of numerous objects in its field it should focus on. Because of this, I frequently use manual focus, but bear in mind I also shoot almost everything from a tripod and bracket everything. When the bird is in the air, my AF is definitely on. Auto-focus in today's cameras is pretty damn good, and allows for some really useful options like predictive AF which tracks a moving subject and keeps the focus primed for the shutter release. I can't imagine a sports photographer doing without AF.

The N90S is a good camera, and not only allows for shutting off the bells and whistles, but for interchangeable focus screens if you find that manual focus is difficult. You can also focus and lock. Intended as a semi-pro camera, its AF system is faster and more accurate than the lower-end, consumer-oriented models. Take a look through the viewfinder at a local camera store to tell you more, and try out manual focus yourself with a slower lens inside the store, to tell you what you'd be facing. You can't trust auto-focus completely, but it's far from being completely worthless either.

And bear in mind that many articles are written from a professional standpoint, who feel that the difference between a 50mm 1.8 and a 1.4 is important enough to spend an extra $900 or more on.

Just my too-sense. - Al.

--
Remove 'onspam' for direct reply.

[Ed. note: Mr. Small is an expert and author on Zeiss and related optics etc...]
From Rollei Mailing List:
Date: Mon, 27 Dec 1999
From: Marc James Small msmall@roanoke.infi.net
To: rollei@mejac.palo-alto.ca.us
Subject: Re: [Rollei] How to Use Rolleinars

DX2@CU.NIH.GOV wrote:

>Even though I have a Maxwell screen, I had some difficulty in
>knowing if I was in focus.

No! It isn't EVEN though, it is BECAUSE you have a Maxwell screen that focusing is difficult! All of these "bright screens" render less precise focusing than the older "dim" screen. Prove this for yourself: compare, say, a 2.8GX and 2.8F Rolleiflex TLR, or a 500C and CM Hasselblad.

In other words, the price of that bright image is less precise focusing. When I'm doing a shoot in a really dim arena, I tend to take my 2.8F and leave the 2.8GX home.

Marc

msmall@roanoke.infi.net

From: Roger N Clark rnclark@uswest.net
Date: Mon, 27 Dec 1999
Newsgroups: rec.photo.technique.nature
Subject: Re: use of auto focus?

Guy Washburn/Laura Reiner wrote:

> Interesting I should give it more of an honest try. I work with birds
> primarily in af servo mode. With af on the shutter button one shot never
> seemed to work out for me.

If I remember the operation correctly, servo mode means the camera ATTEMPTS to track the subject, but when you press the shutter, the frame is taken, regardless of focus. If you want focus lock, don't use servo (check manuals on this). I stopped using servo on my EOS Elan most of the time. I find I can press the button plenty fast enough and with experience, anticipate the mirror delay so that I get the peak action (at least more of the time--I think). Action is usually not contiguous, so you don't necessarily need a series of uniformly spaced (in time) images, just key points in the sequence, like the instant the eagle grabs the fish out of the water.

> More tricks for an old dog... (maybe I should get the EOS 3 manual out
> again?) It sounds interesting. But will it replace using depth of field
> preview as part of choosing your composition?

No. My Elan has a depth of field preview. I used a custom function to program one of the buttons for it. I use it sometimes.

> Does it make the effect of the
> GND filter more visable?

Depth of field preview does help see the gradient neutral density filter line. I use the preview all the time when using a GND.

> IS while liberating for many folks is not really a substitute for a good
> tripod and good technique or  for most  landscape or nature (fast lenses help
> here too). That said I do fancy the 100-400 IS for work in a floating
> blind...

I agree. I use a tripod whenever I can, even to the delay and annoyance of those hiking with me! But often the IS means getting the shot or not. Like when you/re hiking and come upon an animal. You may only have seconds (I wear my camera on my chest, not in my backpack) and no time to set up a tripod (I also wear the tripod on my chest-attached to a backpack strap with a carabiner), (Unless its the 4x5 tripod-- that's too heavy so stays in the backpack.)

> But autofocus is not
> perfect and neither is matrix metering AE, IS, eye control or any of the
> other great things technology has brought to photography in the past 15
> years. Understanding this imperfection and knowing how to control it to your
>personal  vision is what separates a photographer from a snap shooter.

I agree. Know your equipment, It should be a good friend. I used to bracket all the time. With experience, I've learned what my camera can and can't do. I rarely bracket now. I usually know when the metering system might be fooled, then I bracket. And I rearely have an improperly exposed slide.

This summer I got a 500 mm lens (previously limited to 300mm). I "lost" a lot of shots due to camera shake. I then upgraded to my heavier bogen tripod (which I use for 4x5) when using the 500mm (and EOS Elan) and my shots were much sharper. You must learn ALL your equipment, and how it performs in each situation as an integrated system.

> It would be nice if they do it a a price less than my 600mm lens too. Till
> then a scanner will have to do.

Someday. Just think how far electronics have come in 10 years, and exponentially project 10 years into the future--20 megapixel digital cameras with 50 gigabyte flash cards! Let's hope it happens.

Roger Clark

Date: Sun, 26 Dec 1999
From: A. Server alant@bdm.local.com
Newsgroups: rec.photo.technique.nature
Subject: Re: use of auto focus?

Joseph,

Might I suggest that your friend might be experiencing a bit of "selective seeing"? Is it possible that your friend is actually equating the use of newer/more expensive 35mm gear with "professional" and "semi-professional"? That is, he simply fails to record those who are not using the equipment of which he clearly approves?

For one, identifying a professional photographer in the field might be a trick in that he is highly unlikely to come with a large, illuminated, sign that says "here is several tens of thousands of dollars of portable, easily fenced, equipment in a vehicle miles from anywhere". Second, few wildlife professionals wish to work in a crowd. That is, you are relatively unlikely to encounter them working. Finally, what happened to all of those who do not use 35mm at all? Those images that are described later in your post are admirable, in part, because of the larger film image.

FWIW, I use an N90s and a couple of FM2s as backup and alternate film/lens bodies. With them I use a selection of mostly prime lenses about equally distributed among AF and non AF. (some are over 30 years old, a tribute to the F-mount's longevity)

I find the AF on the N90s usable, but often annoying. Hazarding a guess, I would say that I tend to switch to the FMs whenever the situation demands faster composition. Guessing further, about 70+ percent of the time, I use the N90s in either pure manual or aperture priority mode. (IMHO autofocus is pretty much useless for stationary macro protography and equally unneeded for landscape photography) Also FWIW, I have purchased two N90s's, both new, so I must like something about them.

Ultimately, you are going to have to use the system, not your opinionated friend. Do you have a reason to think that you require autofocus for the type of photography you wish to pursue?

I would highly suggest that you bias your investment towards more and better lenses with correspondingly less concern with the camera body. The camera body is seldom responsible for the success of the photograph. The photographer and the lens usually are.

-regards,

PS. You might wish to rethink your choice of the 6x7.

......

Date: Tue, 14 Dec 1999
From: Mac Breck macbreck@timesnet.net
To: rmonagha@post.cis.smu.edu
Subject: Auto Focus Problems Page

While I haven't read your whole Auto Focus Problems Page yet, I'd like to ask if you touched on this subject: manually focusing the AF lens, you are often fighting gear train resistance, motor resistance and inertia, and gear slop (play in the gear mechanism; once focused in a spot how much can you turn the focus right left and right before you hit any resistance). Just try a 60mm f/2.8 AF Micro-Nikkor on a Nikon manual focus body, and try to focus in the 3 ft. to infinity range. It's horrible! I sold my 60mm f/2.8 AF Micro-Nikkor and bought a Mint (KEH "LN") condition 55 f/2.8 AIS Micro-Nikkor, PK-13, and pocketed $50. Now I'm happy.

Mac

Date: Mon, 30 Aug 1999
From: philfflash@my-deja.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Focusing Manually on a New AF System

.....

The focus-ability of autofocus lenses may be something rather individual. I HAD to switch to autofocus, I simply wasn't getting good focus at all with cameras I had used for many years. Now I find I can focus my Elan quite well - In the right situations. I cannot focus ANY camera quickly. I chase bugs with a 50mm macro and a 2x telextender. The view is bright enough at f 5.6 for me to focus manually. Macro focusing is one of the failings of autofocus since the lens has to go great distances to focus and if the camera picks the wrong direction, you have a real wait. The setup is on the very edge of autofocus ability at all, and wouldn't work except in bright sun. So is it harder to focus the camera manually? For me - No. This does not mean the same would be true of everyone.

As to split image, and other focus aides. When you use too long a lens, or too dark a lens, they go black, and you have to focus around this useless blotch in the center of the screen. Other than that my experience has been that they work fine.

--

Date: Mon, 30 Aug 1999
From: a@bc.com (Bertus)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Isn't buying a used manual camera a bad idea?

"Jim Williams" jlw@nospam.net wrote:

>The focusing screens in most AF cameras aren't as "textured" as those in MF
>cameras -- this makes a brighter image, but makes focusing more difficult.
>And AF camera finders usually don't include any form of focusing aid such
>as a split-image rangefinder or microprism.

absolutely spot on!

===========
Bertus
mr.bass@planet.nl

[Ed. note: TC are teleconverters 1.4x.. ]
Date: 20 Dec 1999
From: mrscience9@aol.com (MrScience9)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Nikon 300mm f4 - Tamron SP 1.4 or TC-14E

Scott,

As some others have mentioned, the TC14E cannot be mounted on the 300 f4. You would need the TC14B and then you would lose auto focus and setting apertures with the camera. I've used the 14B and the Tamron 1.4 on this lens. Until the N90s the auto focus was so slow that it was unusable so I sold it and used the TC14B which I had anyway. When I got the N90s I found the autofocus improved to the point where I bought a D version of the Tamron and liked it alot. The Nikon's are better but for this lens the Tamron 1.4 will give you all the connections and very good results.

Harvey

Date: Mon, 1 Nov 1999
From: "Fred Whitlock" afc@cl-sys.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Why do Nikon MF lenses cost more than AF lenses?

Because they use metal helicoid focusing and metal barrels. In other words, they cost more to manufacture. Good shooting.

Fred
Maplewood Photography
http://www.mapelwoodphoto.com

pootz@my-deja.com wrote

> Why do the cost more?
> Do they have better optics?
> -Steve

[Ed. note: possibly interesting general response note...]
Date: Fri, 17 Dec 1999
From: Robert Monaghan rmonagha@post.cis.smu.edu
Subject: Re: http://www.smu.edu/~rmonagha/third/af.html AutoFocus problems

Hi Tom,

Thanks for your interest re: af problems page ;-) I am trying to balance out all the ads and articles and paid pro pronouncements, with only one site ;-)

The short answer is that below the article's text and quoted test data and article info, you will find scores of unsolicited comments by AF owner/users citing problems they have experienced - I have only picked one or two rather than listing every single one, so this is just a sampling to show that lots of folks have noticed one or more of these issues. Lots of those posters complain that they have to touch up the AF focus point as it isn't sharp etc.

Others say they turn AF off for 80-90% of their shots - not for the finger exercise, but to avoid these and related problems etc. This isn't some magazine article results, but real-world users reporting real-world problems.

You are right that depth of field often covers up focusing errors at f/5.6 or f/8 that would be critically clear in AF doing portraits at f1.4 or f/2 or even f2.8 (as with the 60mm macro lens reported on in the article).

I don't find this to be 0.00000000000001% of my photos, actually, a lot of us take full face portraits at f/2.8 and use limited depth of field tricks to isolate out subjects with f/2.8 or faster settings. But due to these problems, we have many AF cameras that use lenses so slow - often f/5.6 and slower, that the users won't see this problem, but will also be severely limited in doing many kinds of photography as a consequence, right?

Personally, I do a lot of medium format work, and so I am spoiled by the use of 5x chimney magnifiers on my blads and bronicas, waistlevel finders with 2x and 3x magnifiers on 6x6cm square ground glass fresnel screens, and prisms with highly magnified (3x etc) images (vs. 0.72x on most 35mm SLRs).

But even on 35mm, I have nikon sportsfinders for fast action shots (with F and F2 motordrives..) and pop-up out-of-the-way closeup magnifiers for use with macrophotography which are also handy with other shots. Given the cost of most lenses and 35mm SLR setups (esp pro models/lenses), the cost of a popup magnifier to ensure getting accurate focusing is not that much ($40 up?) If you are trying to get the most out of your lenses, using a tripod etc., then a focusing aide seems like a minor cost piece of insurance to me.

AF cameras are now sold to 90%+ of buyers, but as my long list at the end of my article indicated, the tradeoffs for such focusing convenience is a long list of gotcha's and places where typical consumer AF falls short. You won't find this list of warnings in any of the ads for AF, though ;-)

For those who are doing pro action sports, or the few well-heeled buyers who can afford fast pro glass (f/2.8 or faster telephotos at 300 and 400mm etc) who are doing fast action shots, I think AF is probably a useful tool. But good sports photos were taken in the past without AF, using prefocusing and other tricks, and many of us don't shoot even 1% of our photos which would be improved by AF over manual focus.

I still have some AF lenses left from my AF testing (no bodies anymore..), the lenses are optically capable, if different feel, but I still like the manual focus lens feel better for manual focus bodies - most folks do. In fact, as I have noted, AF lenses are now being made with more manual focus friendly features (wider grips etc) as makers have discovered how many users are turning off AF and using MF and didn't like the old thin grip

In conclusion, I think AF is a solution for a very limited set of mostly professional sports and fast action photographers who can afford the high end pro bodies and fast glass needed to make AF work well. These folks refuse to use the N60 style AF which is what the average 35mm SLR consumer is stuck with; just try to get one to lend you theirs and try yours!

On the other hand, AF is a poor choice for many types of photography (esp. scientific, astro, macrophotography, portraiture...) which I feel is rather a bad tradeoff and limiting for the average photographer against a manual focus rig...

regards bobm

PS the vision issue has many solutions, depending on the problem (diopter lenses, astigmatism correction, bright-screens, sportsfinders, split screens and rangefinders, fast glass, magnifiers, and so on. AF is only one solution, and often not the optimal one...

[ed. note: see Fading Vision? Solutions for Photographers pages...]

From Nikon Mailing List:
Date: Mon, 25 Oct 1999
From: Jonathan Castner jonathan@jonathancastner.com
Subject: [NIKON] Re: AF fiddling

Robert Ades asked me:

If you use a standard AF Nikon prime lenses (like any 50mm, 85mm, 105mm etc.), does it bother you that when you attach a Nikon teleconverter you loose autofocus capability? If you wanted to manually adjust an AF lens (other than AFS lenses), does it bother you that you have to flip a switch?

To both questions: Nope, not in the least. Ya see, I manually focus my pictures. I find AF to be generally useless. Except for the times when I am holding a flash in my left hand, all my pictures are made manually. I don't use teleconverter for short lenses. Why would I want to put a TC on a 50mm lens? I already have a fast 85mm and 105mm and 80-200?? I do have a TC14B for my 300mm f/2.8 and 500mm f/4.0 and my soon to be arriving AF-S 400mm f/2.8. The TC14B also doubles on my 80-200 f/2.8 but then I manually focus that too.

Jonathan Castner -Photojournalist
Online folio at: http://www.jonathancastner.com

[Ed.note: fatal spreading lens incompatibility? - spreading an "electronic plague" between AF lens and bodies?]
Date: Tue, 26 Oct 1999
From: calvinvu@yahoo.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Reliability of Camera Electronics

frostycat@my-deja.com wrote:

> >Friends who own Canons have had no problems.
> No experience.

I've had problem with Canon autofocus. It started with my bro's Canon Rebel and a 35-80mm lens and the autofocusing didn't work. I tried my Sigma 28-70 lens on that camera and it worked so I gave him that lens. He called me up only a few days later and said that the autofocus only worked with the Sigma a few times and then it stopped working again. I tried both broken lens with my own EOS 10s and both are as dead as a nail so I assumed the Rebel has some electronic problem that burned the autofocusing circuitry in those lens.

Shortly after that my own EOS 10s developed the same problem with a 50-200mm L lens, my favorite lens. I can't remember if I ever tried that lens with the bad Rebel or not so I don't even know whether this new problem is a problem in my camera or in the lens itself.

Anyway, I got fed up with the spreading electronic plague and gave both my EOS 10s and the 50-200mm L lens to another brother so I never found out what really happened to them. I just bought a brandnew set of Canon camera & lens and make sure I stay away from those old diseased equipments.

From Nikon Mailing List:
Date: Sat, 30 Oct 1999
From: Simon Freidin s.freidin@medicine.unimelb.edu.au
Subject: [NIKON] F5/F100 focussing points

I'm not satisfied with the positioning of the 5 focussing points - they rarely fall on a position of interest within the composition (ie eyes, main subject, or point of sharpest focus). So I still end up focussing and moving the camera - though not as much as with single point focussing.

Rather than a cross configuration, I'd prefer a "corners of the square" - - at approximately the intersection of thirds when sides of 35mm is cropped to 4x6 (or 8x10, 12x16,16x 20) enlargement.

.....

I'd also like the etchings on the E screen to match the thirds, but that's another story. What do other list members think?

regards
Simon

From Nikon Mailing List;
Date: Sat, 30 Oct 1999
From: Chris McKernan chrismck10@home.com
Subject: Re: [NIKON] F5/F100 focussing points

Simon if you're refering to having the focus points on the four intersecting points when dealing with the rule of thirds, I'm all for it... not a bad idea.

And while they're at it, make the focus points RED as it makes them easier to see.

Chris

.....

Date: 30 Mar 2000
From: pburian@aol.com (PBurian)
Newsgroups: rec.photo.technique.nature
Subject: Re: Image Stabilizer on BIG lenses, why?

> Still kind wondering what good IS is on lens over 300 2.8 , nobody hand
>holds them. I think its a marketing plan.

Not entirely. Here are the advantages:

1. Sports photogs generally use monopods.

2. The IS with the NEW SUPER TELEPHOTO LENSES ONLY does work even on a tripod and helps eliminate vibrations.

3. When you shoot from a boat, a floating dock or other unstable platform, IS is useful.

4. When you shoot from a car or Land Rover, IS is very useful with any lens.

5. Some paparazzi do handhold 500mm f/4 lenses.

But sure, it is more essential on shorter lenses that are frequently hand-held.

Peter Burian, PHOTO LIFE magazine
see also www.photolife.com

Date: Sat, 23 Oct 1999
From: Anders Svensson Anders.-.Eivor.Svensson@swipnet.se
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Nikor Manual vs Autofocus (not trolling)

Del Toyd skrev:

> > Robert Monaghan wrote 
> http://www.smu.edu/~rmonagha/third/af.html
> > there are lots of issues with autofocus you won't find discussed in the
> > ads or promo articles but which could impact your style of photography...
>
> Bob,
>
> This was a great article, one that I will have to reread several times to
> fully understand all the info packed within.  I wanted to ask you what role
> you thought USM/AFS lenses have in the discrepency between AF and MF
> resolution?  It seems to me that the high-torque piezoelectric motors in N's
> AFS and C's USM lenses are much more accurate (i.e able to stop on the
> "sweet spot" more precisely) than N's low-torque DC motor and
> screwdriver-driven conventional AF lenses.  It is my belief that the reason
> Canon was much superior to Nikon when AF resolution was compared to MF
> resolution in the Pop Photo article you referenced, was in large part
> because of the USM technology which would seem to be inherently more
> precise, all other factors being equal.
>
> Any comments?  Thanks again for the interesting techno AF review.
>
> Del

I also read that article and found it thought provoking and in many areas in consistence with my own thoughts.

There are some comments that I want to make.

One is that the AF performance glitches are to a large degree masked by the difference between real world photographic objects tendency to be three dimensional... :-) This means simply that on non flat objects, some point *is* likely to be in "perfect focus" and for a lot of objects, the location of the precise focus spot isn't important.

Secondly, AF cameras are making it possible for amateurs with bad eyesight to get better results than otherwise, make it possible to photograph (focus) moving objects more efficiently, make up for sloppy (perhaps non-knowingly) focusing technique and so on. These are propertys that may have value for a lot of photographers. Or, if you want - you do need to add care and skill to manual (non AF) cameras to get sharp pictures out of them...

***

As for the difference between Nikon and Canon, and wether that difference is a function of focusing motor drive - I don't think these tests tell the story either way.

I feel that the differences in SW algorithms - deciding how to interpolate, how and wich way to add adjustment, and also important, knowing when to say "enough", stop fiddling and allow the shot to happen - are more important differentiators.

As a side comment: A AF sensing system using too long time to arrive at a "sharpness solution" will hinder more than it helps. It will, however, look extremely good in a static sharpness test. This is also a argument for the two stage firing button, that senses the photographers intentions and fires unconditionally when there is more than normal pressure - like when a excited photographer pushes his AF finger blue, just to*get that Picture*... :-)

Canon is also using different technology for their sensors, using more of them and may therefore arrive to a more precise results - especially considering the fact that Canon allows a wider "base" (and needs larger lens openings therefore) for sharpness evaluation. This is somewhat analogous to a wider split range finder base, even if the AF measuring device looks at other propertys.

Note that to find a significant difference, the AF performance is tested in a situation where most users would agree that manual focusing *is* the better way to go. It is a test, and perhaps not a reasonable approximation of when most photographers would say that AF would be of value.

OTOH, if high torque sonic motors would be the major differentiator, we would get the same/similar results from Nikon AF-S lenses, now using the same kind of motors.

--
Anders Svensson
Anders.-.Eivor.Svensson@swipnet.se

[Ed. note: some good points above; but photographers with poor vision have been taking photos well past middle age because there are existing vision solutions that don't require autofocus, but are not well known now that autofocus is seen as the "solution" to this problem.

Similarly, I agree that we could craft a test that would show where AF is of value. What I think would surprise most folks is how narrow that range would be where AF was superior to MF. This is one reason AF was around for nearly a decade before taking off in sales (and in the lens AF not in the body, so it could be used on most MF bodies). For a lot of situations in my bottom of the article listing above, AF is at quite a disadvantage. This reality is something you won't see in the ads! ;-)

[Ed. note: work-arounds to use T-mounts ;-)]
Date: Sun, 24 Oct 1999
From: Brian Decker deckerb@charter.net
Newsgroups: rec.photo.equipment.35mm
Subject: Re: T-mount, Manual Focus Lens Problem (Maxxum)

I had the same problem with my 500si, this took care of the problem, They put a "safety feature" in the camera that prevents it from firing if film is present and it doesnt detect an autofocus lens. The following procedures turn this function off.

Camera Procedure

5000, 7000 No preparation needed to use 9000, 3000i, T-mount lenses. 5000i, 7000i, 8000i

2xi, 3xi Use of T-mount lenses, microscopes, Spxi and telescopes is not possible.

5xi Press and hold SPOT and FUNC. buttons and switch from LOCK to ON.

7xi/9xi Press and hold AEL and FUNC. buttons and move power switch from LOCK to ON.

300si Press and hold FLASH and DRIVE/SELFTIMER buttons and move power switch from LOCK to ON. (Off appears in LCD panel)

400si Press and hold Drive Mode and AV buttons and move power switch from LOCK to ON.

500si Press and hold Drive Mode and SPOT buttons and move power switch from LOCK to ON.

600si Press and hold the LENS RELEASE button and FILM SPEED button and move the power switch from LOCK to ON. (OFF appears in LCD panel)

700si Press and hold SPOT and CARD buttons and move power switch from LOCK to ON.

800si Press and hold SUBJECT PROGRAM and AEL buttons and move power switch from LOCK to ON.(OFF appears in LCD panel)

XTsi/HTsi Press and hold the Selftimer-Drive Mode button and Spot/AE button while sliding the Main Switch to "ON." (OFF appears in LCD panel)

Vectis S-1 Press ON/OFF to turn camera ON. Open door that covers hidden buttons. Press the Drive Mode button (fathest on the left) and the MODE button together. "ON" will appear in the LCD panel. Press the "SEL" button (second from right in hidden buttons). "OFF" Will appear in the LCD panel.

RD-175 Press and hold DRIVE/SELFTIMER and AV buttons and move power switch from LOCK to ON. (ON" appears in LCD pane)

CERoberts wrote:

> I recently purchased a Pro Optic t-mount 420-800 M/F lens.  The user's guide
> that came w/ the lens states that it will work on Minolta Maxxum cameras (in
> aperture mode).  However, the shutter remains locked no matter what I do!  I
> am curious to see if anyone knows how to correct/override the shutter lock.
> Any helpful advice is appreciated.
>
> For anyone wishing to tell me what a crappy lens this is or how I should
> spend my money, please don't respond.
>
> Thank you,
> CER

Date: Sun, 10 Oct 1999
From: "Chris Lee" chrislee1@home.com
Newsgroups: rec.photo.equipment.35mm
Subject: AF and Image Quality: Answer From Zeiss

I have received a private email from the very generous Mr. Kornelius J. Fleischer, who is the Head of Camera Lens Applications at Zeiss. He is also the editor of Zeiss' "Camera Lens News" and frequently participates in the Medium Format Digest.

The email answers the following question:

***********************

Q: Do autofocus lenses always have to be inferior?

A: Not necessarily! If you take care that tolerances are as narrow as requested and don't sacrifice those for the sake of low manufacturing costs, or easy first pass yield. At Zeiss, we appear to like optical performance clearly better than financial performance...

***********************

Some people assume that just because a lens is AF, it MUST have lower mechanical and optical precision. That is purely false. While it's undeniable that some manufacturers tend to use plastic elements and lens barrels to speed up AF performance, it's also true that if due care is taken, AF lenses with as good mechanical/optical performance as MF lenses can be produced.

One very good example is the new Zeiss lenses for the Contax 645. The lenses not only have excellent construction and very smooth manual focusing like non-AF lenses, optically they also perform stellar. The recent issue in Color Foto has confirmed this statement, proclaiming the Zeiss Contax 645 lenses excellent and some of them the best yet to be seen in their respective categories.

Date: Sun, 10 Oct 1999
From: Tom Hunscher afterglo@teleport.com
Newsgroups: rec.photo.technique.people
Subject: Re: Focus Auto or Manual?

Stephen:

There is no guarantee that the autofocus would focus on the eyes. It would probably focus on the whole face and pick an average of some sort, which would be close but possibly no cigar. Perhaps you need to get glasses, or if you already have them, get a new prescription. Or possibly you need a bit more light on your subject as you do your focus. I work a lot with models and I often find ambient light isn't bright enough for me to do a focus, so I have the model put an open hand over wherever I want to focus. I focus on this, then have her get back into position. Since your work is more close-up, this procedure won't work for you, but maybe it'll give you an idea or two.

Tom

*****

Stephen wrote:

>         I only have a 35 mm camera (Canon Elan IIe) and I was wondering
how
> often do the rest of you depend on your auto focus?  I believe that
> most medium formats do not have auto focus (if I'm wrong here, please
> be gentile in your flames) so I understand you don't have a choice, but
> for those that do, which do you use for portraits?  I have a hard time
> telling if the eyes are focused (my goal for portraits) when I use my
> lens at anything 200 mm and above.  Maybe I should get my eyes checked,
> but that is another issue all together. :)
>
> Stephen
> --
> "Anything for you"

Author of "How to Recruit Models for Nude & Erotic Photography"
http://www.teleport.com/~afterglo/aftbooks.htm

Date: Mon, 11 Oct 1999
From: "Chris Lee" chrislee1@home.com
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: AF and Image Quality: Answer From Zeiss

Don't mistake focusing accuracy with quality of optics. The two can be entirely independent of each other.

It's undeniable that careful manual focusing can yield better focusing accuracy than AF given current technology. (This has been shown in a recent Pop Photo article.) But that doesn't mean the AF lenses themselves have intrinsically worse quality of optics if compared to MF-only lenses. (And this is precisely what Kornelius meant.) In other words, AF need not have an effect on the quality of optics--the difference is only in the AF mechanism. You can expect similar results if you choose to manually focus AF or MF lenses, assuming they are based on identical optical designs with high production standards.

AF is for convenience and speed. When focusing accuracy is important, manually focusing the lenses is always preferred.

----------
jbh@magicnet.net (John Hicks) wrote:

>  "Chris Lee" chrislee1@home.com
> wrote:
>
>>Q: Do autofocus lenses always have to be inferior?
>
>   I don't believe there's any real question about AF lenses being
> inferior to equivalent-quality MF lenses; the problem is the AF system
> itself.
>   And the question should be: Is (brand X) AF superior or inferior in
> focusing accuracy to a careful photographer manually focusing the same
> camera?

Date: 11 Oct 1999
From: rick5347@aol.com (RICK5347)
Newsgroups: rec.photo.technique.people
Subject: Re: Focus Auto or Manual?

I use Canon A2s and their lenses in my wedding work. My opinion of suto focus is that it is a tool, like everything else. I use it when it benefits me and turn it off when iy hinders me. Some Canon lenses "autofocus" faster than others, some are shot-losing slow, like my 75-300 IS and 85/1.2. Those lenses are usually left on manual focus.

The important thing about auto focus it to keep in mind that, as a tool, it can also be turned off. In my seminars I often state that the term "auto focus" is a poor translation from Japanese, the better translation would be "ough'ta focus".

Best regards,
Rick Rosen
www.rickrosen.com

Date: 11 Oct 1999
From: rick5347@aol.com (RICK5347)
Newsgroups: rec.photo.technique.people
Subject: Re: Focus Auto or Manual?

In fact I agree with Nikon's approach with the F3 where it will work at 1/90th which is it's flash sync if the batteries go dead. For wedding work this can be an asset.>>

So can carrying a spare battery.

I carry four spare batteries and three A2 bodies to every wedding. That weird 6V battery in the Canons seems to last me about 5 weddings (about 150 rolls) until the battery meter shows *half*, then it is replaced. What I have found is that as the battery gets weaker, beyond that *half* position the autofocus slows as does the fast rewind.

Best regards,
Rick Rosen
www.rickrosen.com

Date: Tue, 21 Sep 1999
From: Godfrey DiGiorgi ramarren@bayarea.net
Newsgroups: rec.photo.equipment.35mm
Subject: Re: active vs. passive autofocus

Active autofocus systems use either echo technology (Polaroid cameras use acoustic echos to evaluate distance, like sonar on a submarine) or triangulation (a projected IR beam reflected off the subject is received by a pair of prisms or mirrors, which then evaluates how much movement of one of the prisms is necessary to make the received signal coincident). The results of this evaluation are fed to the focus servos which rack the focus to the appropriate point.

Passive autofocus utilizes available light: sensors each receive a signal through their lenses and the signals are compared to one another electronically. The focus of the receptor system is varied until the signals coincide in their characteristic, which sets the appropriate signal for the lens focus servo.

Norman Goldberg talks about these systems in some detail in "Camera Technology - The Dark Side of the Lens".

The Ricoh GR1 uses a passive autofocus system with a focus assist grid in low illumination circumstances. The way the receptors and comparator is rigged makes it difficult for it to evaluate focus on subjects which have no vertical differentiation - horizonally running blinds will often fool it. In such circumstances, just turn the camera to a bit of an angle and let the focus lock in properly, then re-frame the picture. I've found the GR1's focus capability to be more than adequate for most anything I've needed.

Godfrey

> Nancy Harralson wrote 
> >Please explain the difference in these 2 types of autofocus. My Gr1 is
> >critiqued because of passive autofocus. Is that a negative?

From Nikon MF Mailing List;
Date: Thu, 23 Sep 1999
From: "Roland Vink" roland.vink@ait.ac.nz
Subject: Re: Manual Focus Feel of AF-S lenses

> Can anybody give me their opinion on the manual focus
> feel of the new 80-200 and 28-70mm AF-S lenses?

Hi Paul,

These lenses have an AF/manual switch, similar to my AF 105/2.8 micro. In manual mode my lens has a good amount of drag unlike other AF lenses, but it doesn't have the silky smoothness of AIS lenses.

If you can, try going to a shop which has AF-S lenses in stock and get a feel for them yourself.

Roland.

From Rollei Mailing List:
Date: Thu, 23 Sep 1999
From: Bob Shell bob@bobshell.com
Subject: Re: [Rollei] 6008E vs. 6008 integral?

How in-the-know is your source?

I ask because Rollei is very open with me about forthcoming stuff, and all I've heard about is new point and shoots.

I know that they are hard at work on an autofocus system, but I don't expect to see that soon.

Zeiss has done some prototype autofocus lenses, but they are clunky like the ones Vivitar and Tamron used to have for 35mm with the complete AF system in the lens. They worked OK, but were total dogs on the market. I doubt if these Zeiss lenses will ever see the light of day since they would not work as well as the Contax 645 and would be frighteningly expensive.

As for what they could add to the 6008i, well they could take all that stuff the Master Control unit does and incorporate it into the body. That probably would not be hard to do.

Rather than AF, they might go the route that Contax did with the RX and put an in-focus indicator in the viewfinder. I think many of us would be just as happy with that as with full AF. In working with the Contax 645 I have found that it is no big deal to use the 120 manual focus lens and use the in-focus indicator in the viewfinder to help establish focus.

Bob

> Well....
>
> And I have heard, from a fairly in-the-know source, that Rollei is coming
> out with a new top-shelf model sometime in the next.  That would affect the
> used 6008i market somewhat, I imagine.
>
> Then again, I can't imagine what features they could *add* to the 6008i,
> unless they do up some AF lenses -- which would cost more than a house -- to
> compete with Contax and Mamiya.  Who knows?  As for metering, sure, yeah,
> it's great -- but with MF, I always shoot manually.  Always.  Just 'cuz.
>
> I will call Wall Street and some other dealers tomorrow to get more of the
> skinny on this rebate.  For a 6001 with a back, it's a bargain, by my book.

From Rollei Mailing List;
Date: Thu, 23 Sep 1999
From: Bob Shell bob@bobshell.com
Subject: Re: [Rollei] Novoflex

> These lenses are AF with whatever camera they're mounted on?!

Yes. The ones Vivitar sold (a 28-80 and 70-200 if my memory is right) were made by Cosina, which holds some important basic patents in AF. They worked very well. I got my dad one of the 28-80 one for his Pentax MX and he still uses it. Optically they were very good, but focusing action was a bit slower than we are used to today. They made them in most common lens mounts, Canon, Nikon, Pentax, Minolta.

The Tamron one was also something like 70-200 and used their Adaptall system so you could put it on almost any camera. It's AF wasn't as good as that from Cosina, but was OK in bright light.

I haven't seen any mention of these lenses in years.

Bob

[Ed. note: another creative work-around to use T-mount lenses...]
Date: Sun, 26 Sep 1999
From: ted1953@usa.net (Ted)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: T2 lens on Minolta 500si dynax

sspiers@aol.com (SSpiers) wrote:

>After buying a 500mm T2 lens for my Minolta 500si the camara is no longer aware
>of it's appature.
>I have been told that by pressing a number of buttons together this will allow
>me to tell the camara the appature setting.
>Does anyone knoe the secret formula?????
>Thanks
>Simon Spiers

Would you happen to know the first 4 digits of the product code on the bottom of the Minolta box your camera came in? My override list is by model code.

If your Dynax 500si have a plastic bayonet mount? (first 4 digits of the product code on the bottom of the box is 2099) if so try this:

Make sure the camera is turned-off. Then while pressing and holding the Drive-Mode/Self-Timer button and Flash-Control button, slide the Main Switch to on

If your 500si has a metal bayonet mount (first four digits of the product code is 2151) try this:

Make sure the camera is turned-off. Then while pressing and holding the Drive-Mode/Self-Timer button and Spot button, slide the Main Switch to on

Date: 13 Sep 1999
From: jorth4810@cs.com (JOrth4810)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Galen Gindes: Auto Focus Today

...snip

>My 50mm 1.8 Olympus lens produced pictures that put the F 5 to shame. This is
>not a problem of the photographer but with the equipment? So, why not always
>use manual focus? The problem is that focusing screens are much darker than in
>the good old days because we have become accustomed to slow zoom lenses.

You actually have an interesting point here. Maybe it's me, but since I've gone autofocus, my pictures seem to have become worse. My manual (and manually) focused pictures seem sharper. I've drifted away from AF and recently decided to not get the Minolta 800si...instead I'm going back to "school" with my old AE-1, and mint TX I picked up, and nice 28/2.8, 50/1.4 and 135/2.8 FD lenses I started with 16 years ago. (But I'll still keep my 70-210/4 zoom in the bag, too).

Date: Mon, 13 Sep 1999
From: "Shrike" shrike@netcom.ca
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Galen Gindes: Auto Focus Today

Actually , the results are not that surprising. When you focus on anything other than a flat wall that is perpendicular to the lens axis, I think you will always have some "play" in what is being focused on. For example, focus on a persons face at f2.8, is the camera AF sensor focusing on the tip of their nose, their cheek, etc. At small apertures , and uneven subjects , how the hell would it know what you want to focus on? And really, what do you really need AF for anyway? Landscapes? ...No....Macro? ....No. Sports or action ?....Yes. Eyesight problems? Yes. I fail to understand why everyone applauds AF when you are far better off manually focusing for most situations. I mean, the 45 AF points in the EOS3 are real handy when your doing landscapes.

....

Date: 14 Sep 1999
From: fchldray@aol.com (FCHLDRAY)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Galen Gindes: Auto Focus Today

In regard to the issue of Popular Photography test reliability versus that of Amateur Photography--I would note the following.

Approximately a year and a half ago Popular Photography acquired the use of extremely sophisticated equipment for the testing of cameras and lenses. They detailed this new equipment and, shortly thereafter, they began to publish specific data on cameras and lenses that they had not published before.

To my knowledge, no amateur photographer or other photographic magazine or website has access to this type of equipment. No magazine publishes the lab test data that Popular Photography does because they don't have that equipment.

Which brings us to the way pictures look in a magazine. Unfortunately, the quality of reproduced pictures does not accurately reflect what they really look like. The printing in magazines degrades the images.

I'm not here to question the integrity of Ameteur Photography as I only have a vague recollection of reading a few issues. That recollection included less impressive camera and lens tests.

It should be noted that in accessing the opinions and test results in any magazine, one should thoroughly look at the methodology of the study. The Popular Photography study was not a "fluff piece." The authors gave a detailed explanation of the study methods and the manner in which they came up with their results, restested the cameras and rechecked the results. This, I understand, involved one month of extensive lab testing.

Popular Photography has little motive to rag on Nikon since Nikon spends a fortune advertising in that magazine-much more than in any other magazine published in the United States. No one likes to bite the hand that feeds them and they need advertising revenue. With all that said, I would put my chips on the Popular Photography results. Have you read the Photogragic(Pedersen) tests--or the Outdoor Photography tests---to my knowledge, neither magazine has ever tested a camera or lens they did not "love"--a word often used in both of those magazines. Shutterbug occasionally will publish an extensive lens test but often their reviews are just fluff pieces which don't do much more than recap the advertising pamphlets of the cameras. Lately, the TIPA tests, published in Practical Photography, have begun to give us more insight into the quality lenses. These tests, again, use expensive laboratory test equipment--which is accomplished by a combination of pooled resources of European magazines. Their tests of some of the low end Nikon lenses have yielded dreadful results.

For their own part, Popular Photography, did not use rhetoric or try to slant the article toward any argument other than that auto focus should be improved. They left it to us, amateur, advanced amateur, or pros, to determine if a .46 underexposure in a camera on all pictures was something of importance--just as they left it to us to determine whether a camera that auto focused so it resolved twenty nine lines per milimeter and almost fifty with manual focus--was doing a decent job in auto focus--especially when two other cameras were getting materially better results.

I think the basic theme behind all of this is that camera companies have the technology to make better cameras than they are. The problem is not in available technology but in merchandising. Is it "cost effective" for them to improve their cameras?" Will such improvement sell more cameras?

I also brought up the issue of whether subcontracting the manufacture of certain camera parts, lens parts, and lenses--switching to mass production methods such as substituting molded plastic for ground glass(much more expensive to produce)--retooling new lenses and cameras for production in third world countries with the costs of labor cut drastically--well, I wonder if things are really getting better.

[Ed. note: buying accessories such as flash...]
Date: 13 Sep 1999
From: fchldray@aol.com (FCHLDRAY)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Galen Gindes: Auto Focus Today

As to Gene's notes, I would call his attention to one additional & intentional factor in the design of Nikon Cameras that may give Nikon a distinct disasdvantage in auto focusing. This is the refusal of Nikon to put an infra-red type projector of line patterns which illuminates objects and gives them additional detail-in a grid pattern. Minolta has put this system on their cameras for years. Nikon has held off on the N90s and upwards. Why? Because Nikon has put their "focus assist" on their flash units. Therefore, to get the advantage of lighting up a target with an artificial grid on a Nikon, one must buy into the SB 25+ line of strobes. This causes needless expense and it also makes the camera more awkward to handle. It seems silly to have to put a flash unit on a camera just to auto focus. But isn't this the same philosophy that Nikon applied with the N90-N90s--as opposed to the N70. They eliminated automated exposure and flash compensation bracketing without the purchase of the MB 26 back and they have set a steep price on that little accessory--$275-$300. To me this is a rather sleazy way of attempting to make money.

As far as Gene's lens quality argument, I expected that one to come out. But, in fact, the Nikon 50mm 1.4 scores very well on line resolution tests and outscores the Minolta's older version of the 1.4. In Popular Photography tests, the Nikon 28-105 also did far better in resolution than the Minolta 28-105. Yet both trailed Nikon in the auto focus tests.

Apart from this was the Popular Photography test of determining the deviation in inches at a ten foot shot in auto focusing. How many inches over ten feet would cause the camera's focus light to go out or the camera to refocus on AF? The answer was exactly the same. The range of distance tests supported the lines of resolution per milimeter test.

I do understand that Canon has certain sensors that do not work with slower lenses. However, the best results of any lens-combination were achieved by Canon with a slow F4 28-105 lens. I think this would negate the argument that we are dealing with a lens resolution problem. The use of both a fast pro lens and a slower amateur oriented zoom--and with the Canon, quite an older one as upgrades go--supports the conclusions of Popular Photography.

I don't own a Canon 1n but I do own a Minolta 9xi. While, as Gene's, my evaluations are subjective, I have found that the Minolta 28-105 combination appears to focus more quickly, more accurately, and surely more quietly.

Neglected in the article was the question of whether Popular Photography's comparisons--by setting these auto focus cameras on manual focus--are accurate. In a previous test of auto focusing, Popular Photography had noted that the mechanics of auto focus interferred with the ability of manual focus on auto focus lenses. They found that lenses that could only focus manually had far sharper resolution than auto focus lenses that were focused manually. This has to do with the mechanics of allowing the lens to use the auto focus mode.

All in all, I think the test was accurate and at least provocative and food for thought. Surely, it should give some cause to those who are into SLRs as to how well their pictures are focused. As Keppler noted in the articles, the crystal clear sharpness of "advertising photos" bears little relation to the types of photos these cameras take in less than absolutely perfect conditions.

In the test, the editors set out and illustrated in detail the focusing sensors of each camera, explained how they worked and explained their limitations. They conducted their tests in a manner which did not bias a camera because of the type of sensor used.

Galen Gindes

Date: 13 Sep 1999
From: fchldray@aol.com (FCHLDRAY)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Galen Gindes: Auto Focus Today

>From Gene's post I would like to respond to the following criticisms of
>the Popular Photography study.

1. The first argument made is that the test is influenced by the quality of the three 50mm 1.4 lenses that were used in the test. However, it appears that once a lens locked onto the target ten feet away(which was a black cross), than the resolution in lpm(lines per millimeter) should reflect whether the camera body has focused accurately. Each of these lenses is capable of exceeding the resolution figures given in their best tests.

2.In looking at the numbers, the test concentrated on two. First the resolution in lines per millimeter with auto focus(AF) and the resolution in lines per millimeter with manual focus(MAN).

For example:

The Nikon resolved 47 lines per millimeter(MAN), using the manual focusing of the F 5. However, when auto focus was used, the F 5 resolved only 29 lines per millimeter.(AF) That is a noticeable difference in photography. It should surely concern those who are into macro photography and attempt to use auto focus.

The Minolta 50mm 1.4 on a Minolta 9 body resolved 48 lines per milimeter when manual focus was used.(MAN) However, in auto focus, the Minolta resolved 40 lines per milimeter(AF)--that's a lot more clarity than the Nikon's 29 lpm(AF). Surely the Nikon lens is capable of doing better than that and it did when put in the manual focus mode.

To me, this shows that the difference in focus is not caused by the lenses used but by the auto focusing ability of the camera.

As to the sensors involved, it would appear that once the sensor involved had locked focus, that resolution should be meassured equally between the cameras. The reports of the test contained diagrams of the auto focus sensors of each camera and showed how they focused. From the diagrams and explanations, it would appear that the type of sensor--as long as it did lock on focus--would be irrelevant at ten feet.

Finally, as the article noted, published photographs--especially in advertisements--are crystal clear because they are taken with a lot of light and a lot of contrast. It would appear that as lighting becomes less than ideal and as contrast begins to fade, that auto focus cameras would do even worse than in the studies reported.

As for infinity photographs, I think that auto focusing would depend on the camera's ability to recognize that there is no target that can focused inside an infinity setting and then default to infinity. The clarity of an infinity photograph would depend less on auto focus than on the accuracy in which the infinity definition matches a true definition of infinity. In other words, such would have little to do with auto focus and prove nothing about auto focus It would merely show the camera's accuracy at defaulting to an infinity setting and whether the infinity setting was correctly set..

Each person should make up their own mind. As I have pointed out, auto focus cameras, in other tests, have been shown to have poorer manual focus abilities than cameras without auto focus. This is based on the mechanics of getting the lens to auto focus and the creation of limitations on accurate manual focus.

If, as Herbert Keppler has pointed out, auto focus is commonly recognized as the most critical problem by engineers in the field, than I think this study provides at least some food for thought.

Date: 13 Sep 1999
From: eugenec173@aol.com (EugeneC173)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Galen Gindes: Auto Focus Today

Galen,

One more thing I would like to add is that the astute AF user will constantly press the shutter release lightly to keep the camera focused when the distance changes. This nullifies the required movement that Pop P. talked about before the AF re-focuses the lens.

Of course the problems that Pop P. had in their tests with AF probably don't exist with Tele lenses like 300 2.8's and the lenses that the problem does exist the 24's etc., it doesn't matter because depth of field will cover. Can you imagine a sports photog. shooting a football game with a manual focus Contax? Oh well, Pop P. has to write about something.

Gene

Date: Tue, 14 Sep 1999
From: "Dolph" dolphjames@hotmail.com
Newsgroups: rec.photo.equipment.35mm
Subject: Focus hunting on a Nikon F100 (surprising)

I had the pleasure of going to a local camera store today to test out something I had read on the picture perfect website, in the heading Eos 3 vs F5: AF Shootout.

I picked up an F100 with a 28-105 lens. I focused out the window to about infinity, then brought the focusing point back inside to a computer screen nearby. I focused on it. The camera overshot and had to go back. I did it again; same thing. I did it again. No difference. I thought to myself, "wow, that's terrible". Thinking that I was doing something wrong, I turned 90 degrees and picked another point far away, almost to infinity. I focused there, and brought the viewfinder back inside to something close by. It did it again. I gave it three more tries. No difference. EACH time, the camera overshot and had to go back. I asked a salesman to come over and verify what I had discovered. Keep in mind that he is one of those die-hard 'Nikon people'. I asked him to do the same things I had done. After he had finished, I asked him why the camera overshot each time. He looked at me strangely, and said something to the extent that I was a little picky. Dissatisfied with the subject I had brought up, he went over to his arsenal :) and got a brand new 28-70 2.8 AF-S lens, mounted it, and asked me to try again. To my amazement, even though the AF-S lens was very quick in doing so, the camera still continued to overfocus and have to recorrect itself by coming back.

I gave the camera back and asked for an EOS A2. It had a 28-105 USM on it. I repeated what I had done with the Nikon. Bam, the Canon nailed focus each time. Boy was I surprised. This A2 was nailing focus better than the $2800 setup I had in my hand.

Why does the Nikon always overshoot and have to correct by going back. Does the F5 do this too? What gives?

Date: Mon, 13 Sep 1999
From: see.signature@bottom.com (gary gaugler)
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: Why doesn't Nikon make any Medium format gear?

"Dolph" dolphjames@hotmail.com wrote:

>> Nikon is still trying to figure out how to make 35mm . . .
>
>I think they are doing a pretty good job of it, if I do say so myself.

Gary Gaugler, Ph.D.

From Rollei Mailing List:
Date: Thu, 16 Sep 1999
From: Robert Huckabee exurohu@exu.ericsson.se
Subject: [Rollei] Re: Contax 645 off topic (but Zeiss lenses!!)

I'll add my two bits. I `dry fired' the Contax 645 w. the 80mm lens. It was light, easy to handle and had many useful features. What I didn't like is the +/- 1 EV auto compensation (I often shoot chromes) and the _very_ slow AF. I don't expect the AF to be as fast as the 35mm cameras, but ... Also, the wide/long lenses are muy carro! What price Shott glass!

For now I'll stay with my ole Rollei TLR.

R/ Bob

From Hasselblad Mailing List:
Date: Thu, 16 Sep 1999
From: Mark Rabiner mrabiner@concentric.net
Subject: Re: agmenting my system

.....

A Nikon system is an incredible tool which if you sell off you could feel lost out. At least keep one body and a macro. I'd keep it all. Try one Contax body with one lens first before you go with the whole system. Two photographers in portland who share a studio are both critical of it for different reasons. One says there are AF film flatness problems which make it a disappointment wide open (using a normal lens). The other says he thinks the problem is in field curvature. What ever and if ever it is too new of a basket to put all your eggs in. Keep the Nikons. Use slower film. Use lens hood. Use fixed focus lenes instead of zooms. Don't use UV filters. I have lots of advice! Try the Pentax 645 it has a high and much more established reputations. And is cheaper. I love my Leica M's and my Rolleiflex 2.8 F as well as my Rollei 35. My Nikons collect dust but I will be taking them out to shoot some copy slides this week.

Mark Rabiner

Date: Tue, 14 Sep 1999
From: "Chris Lee" chrislee1@home.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Galen Gindes: Auto Focus Today

> If, as Herbert Keppler has pointed out, auto focus is commonly recognized as
> the most critical problem by engineers in the field, than I think this study
> provides at least some food for thought.

One of the most immediate problems is that most manufacturers tend to advertise AF speed rather than precision, which is rarely talked about. Likewise, users will most likely notice differences in AF speed than precision, which requires more in-depth experiments.

On the other hand, the Contax 645 uses something new for its AF sensor. According to Contax, they have chosen not to use the conventional approach which involves using a small number of linear/cross type sensors, each of which has a few hundred pixels. Instead, they chose to use a 250,000-pixel area sensor to achive greater AF accuracy, or so they say. I have no idea how well the Contax's AF performs in terms of AF accuracy, but at least it signals some kind of awareness of the issue and active involvement in improving and marketing AF accuracy. It is also consistent with Contax's strategy in prioritising image quality.

The Contax 645 includes other features to address the issue of AF accuracy, including the vacuumm film inserts and AF motors that are optimized for precision over speed. Anyone who is interested in the topic can write directly to Contax.

Date: Thu, 2 Sep 1999
From: "Chaoliang" chaoliang@gmx.de
Newsgroups: rec.photo.equipment.35mm
Subject: How sharp is autofocus really? Need advice, please help!!!

Hello, friends:

I've been searching for technical reports about comparison between autofocus and manual focus since several years. But none of the articles I've found could really answer my question: Can autofocus be physically as sharp as manual focus, if the factor of speed does not play a role?

Or put it in another way: I've used manual focus cameras for over ten years. If I'm given enough time for doing fine adjustments on the lenses and cameras, I can usually get extremly sharp pictures. But in my friends circle I've never seen pictures shoot by autofocus cameras being as sharp as mein (I mean only sharp, not good). The pictures are in focus, but still not that sharp. What is the reason? Maybe their cameras are not modern enough? If so, has the modern autofocus technique solved the problem?

This question has tortured me for years. So many times I thought about buying autofocus equipments, but before I get a convincible answer to my question, I just cannot decide. It is not the money the real problem (though it will cost me very much), it is the fear of losing the moments which I just want to catch. You can't get them again. So please, if anyone of you have done some practical comparison or have any such information, please help me.

Many thanks in advance

Chaoliang

Date: Wed, 1 Sep 1999
From: "Don Marcotte" Newsgroups: rec.photo.equipment.35mm
Subject: Testing Nikkor Lens Focus

I'm in the process of scanning 35 years of photos using a Nikon LS30 film scanner. I'm seeing a distressing amount of recent shots whose focus is off for subjects in the distance. When I inspect the original prints, they show fuzziness for longer range subjects. I suspect it has something to do with the autofocus system of my Nikon 6006 with a 35-135mm Nikkor lens. I wonder if it is selecting the wrong aperture for distant subjects or just goofing the range. Is there any way I can perform a good test to find out if I bashed that lens once too often? (Little bashes, though!!).

Don M

Date: Wed, 1 Sep 1999
From: "Only me..." davebg@globalnet.co.uk
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Focusing Manually on a New AF System

> > I obviously use MF in such situations, simply because AF
> > is not needed ...
>
> Why is MF preferable when AF is not required?

You just answered your own question: Because it's not required. If I want to read in bed, I switch on my 30W lamp, not the 100W lamp. Both would do the trick, but one is not necessary. Why are you having a hard time accepting this? :-) I don't use AF if there's no need for it. OK, you do, and that's OK for you, but I fond it get's in the way. If AF is "on", I have to target and focus every shot if I'm not on a tripod, or use AF lock, as unless the subject is under a AF area, it will focus upon the backdrop. If I'm manual, I just focus, and shoot away, safe in the knowledge that so long as the distance hasn't changed, where the subject is within the frame has no effect at all.

> I use AF all the time, and
> only use MF if AF fails to work (which it never seems to do).  I trust AF
> more than my eyesight, even though I have normal vision.  I've always felt
> that, since I cannot examine small details of a normal viewfinder image to
> see how good the focus really is, MF is always just an approximation.

Maybe for you. I find that focusing is very easy to do as accurately, or more so, than using AF. I only use AF when it's faster and more accurate than I am, and that's only usually when it's a moving subject.

David.

Date: Thu, 02 Sep 1999
From: Davis Eichelberger oakhill@swva.net
Newsgroups: rec.photo.equipment.35mm
Subject: Re: How sharp is autofocus really? Need advice, please help!!!

Just a thought, are your comparisons with similar lenses? If you are manually focusing a 50/1.8 quality lens and your friends are autofocusing a inexpensive 28-300 zoom that probably is more of a factor in sharpness than auto vs. manual focus. I use autofocus frequently and haven't noticed it being off often; however, for critical images of static subjects I usually manually focus.

Davis

Date: Thu, 2 Sep 1999
From: "Only me..." davebg@globalnet.co.uk
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Focusing Manually on a New AF System

Jim MacKenzie jim@dusykbarlow.sk.ca wrote

> I don't totally disagree with you, but using that logic, we wouldn't use
> automatic exposure when shooting static scenes, either.

You still miss the point. It's NOT the same at all. Using auto exposure is easier, no matter what you're doing, but using AF for a static subject IS more complex, and DOES take longer.

>The fact is, many
> people do.  Why?  Because it works.

No, it works, some of the time - even most of the time, but manually, if you know what you're doing, will work all of the time. So, if it's a static subject, manual is better suited. That's not to say you should, just that it's better suited.

> Extending the argument, one shouldn't use remote control televisions or
> automatic transmissions except in situations where the TV is unreachable or
> a manual transmission would be a huge inconvenience.  (I drive with a stick,
> for the record, but don't you dare take my remotes!)

No, again, you're missing the point. All those things make the task easier, but using AF is MORE complicated than MF when shooting a still scene! There is MORE to do. Again, I'll run through the differences: AF - a. You have to place one of/the AF sensor over the item you wish to focus upon. b. You have to then lock the focus. c. You then more than likely have to reframe., and d. Finally, shoot. With MF, there is one step only - you focus. SO, how is using AF for a still subject like using auto exposure? Auto exposure is easier for any subject, but AF is more complex than MF when shooting a still subject. TV remote controls make things easier, again, using AF for still life work does not.

Date: 22 Jun 1999
From: "Dan Marder" dmarder@frontiernet.net
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Is Manual Focus Dead??

No operator error, just a design limit. I don't know whether the latest generation has improved on this situation, but I doubt it since emphasis is on speed rather than precision. I wasn't quite right in saying that AF isn't accurate: it's accurate but not precise. Top quality lenses are capable of better than 100 lines/mm resolution, while AF ensures only about half that (unless the lens is stopped down).

Dan

....

Date: Tue, 22 Jun 1999
From: "B B" breivog@teleport.com
Newsgroups: rec.photo.technique.nature
Subject: Hyperfocal Focus with AF lenses?

How does on set the focus distance on AF lenses for hyperfocal (eg, maximizing depth of field from infinity to nearest). Older Manual lenses had a scale engraved which would allow one to set the depth of field at several different f stops. I suppose one could carry a table for the autofocus lens in question and manually set the f stop and focus distance, but it seems that the computer should know how to do this. Especially as this is a classic technique for landscape photography when one wants, for example, a distant mountain with a flower in the foreground, both in focus.

Date: Tue, 10 Aug 1999
From: Roland roland.rashleigh-berry@virgin.net
Newsgroups: rec.photo.equipment.35mm
Subject: Re: SLR reliability for travel in hot, humid countries

Don't take an auto-everything camera to hot humid countries. It won't stay working for long if you put it in your damp warm rucksack or whatever. Manual everything will be fine but they are not fast to use even when you are used to them. You should instead take a camera that will give you automatic exposure but with you having to focus it and set the aperture. Those sort of cameras shouldn't have a problem but you should still try to keep it dry otherwise the battery will discharge through the moisture. I reccomend you keep it in a sealed bag with plenty of silica gel inside it.

DON'T USE ZOOMS when you are on your travels. You will regret it. You may not regret it right away but one day you will see the results of a picture taken with a standard fixed 50mm lens and then you will look at your treasured travel photos taken with a zoom in horror.

I highly recommend the Olympus OM-20 with its standard 50mm F1.8 lens for your travels. You should be able to pick it up for $120 US or so.

If I were travelling with you then I would take 2 cameras. The OM-20 and an OM-2000 body (pure manual) in case the OM-20 packs up.

Roland

Barry Dawson wrote:

> I'm probably buying an SLR for a 6 month trip round S.E.Asia.  Do I buy a
> Canon Elan IIe (fast autofocus, auto everything if I want it), or do I buy
> the Nikon FM2 which is fully mechanical, and will work without batteries.
>
> I hope to visit lots of places off of the normal tourist routes, and don't
> want the camera to pack up on me.
>
> Will an Elan IIe be able to cope with hot/humid conditions?

Date: Fri, 3 Sep 1999
From: "Only me..." davebg@globalnet.co.uk
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Focusing Manually on a New AF System

> to go AF AFTER talking to a number of REAL people that use thier cameras
> in the REAL world and not some lab. If anyone else read this article,
> please share your take on the article.

I agree with the article, only when I'm shooting a static object. I know, by examining my slides, that I can in fact get a sharper image with MF than I can with AF. This is only the case with a still subject however. If I shoot a moving target, then AF will beat me every time. However, seeing as the thread was about the merits of AF when shooting a still life, I have to insist that using it is not only pointless, but detrimental to your work. No matter what certain people on here may think, I'm not anti AF in the slightest. I own 3 AF 35mm bodies, as opposed to 2 MF bodies. I do however, realise that AF is a tool that helps in certain situations, and not at all in others.

David.

Date: Fri, 3 Sep 1999
From: "Only me..." davebg@globalnet.co.uk
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Focusing Manually on a New AF System

> The results of the test on the Canon EOS-1N were pretty much the same. They
> also used an eyepiece magnifier when focusing manually.  I would love to see
> them not use the eyepiece magnifier and run a timer on say a ten shot
> sequence.  Then we could solve the David vs Anthony food fight.

The fact remains that AF is less suitable to MF in the situations I refer to. This is particularly true in a studio, where more than likely (and should be) on a tripod.. Here AF practically cripples you. Besides, I can actually see that AF is doing a less efficient job than I am with still subjects by examining my slides. When shooting wide open at f1.4, DOF is minimal, and any movement of the model AFTER I've locked the AF will result in loss of sharpness. With MF, I have full, and continuous control of focus at all times. These are the things that make AF less suitable. If I was shooting people in the street, or children etc, then I'd be using AF like everyone else with an ounce of sense. All I know is that AF on both my F90X and my F100, and my F5 when I had it, was not as good as I am when it comes to a static subject. For instance, you can actually turn the ring a little and still have the AF's rangefinder indicate that it's focused. This alone would suggest that there's a "tolerance" in the AF system, and that it may not accurately repeat the focus operation time and time again with consistent results. With a moving object the results will be SO much better than I could achieve manually that I don't care, but when I know I can better it, why should I use it?

David.

From Bronica Mailing List:
Date: Sat, 11 Sep 1999
From: geoff/camera tech info@cameratech.com
To: bronica@iList.net
Subject: Re: [BRONICA] TTL flash with Bellows?

>The main point here is that you just get a lot more bang for your buck in
>35mm as it is a bigger market that can finance the more advance technology.
>
>
>
>True, but I think the technology is aimed squarely at the amateur consumer.
>Professionals can certainly benefit from technology, but tend to rely on
>it less. There is no doubt that return on investment in technology is
>driven by volume. Given the lukewarm response to AF medium format camera
>systems by most professionals, I think we're unlikely to see the kind
>of CPU driven metering and AF systems predominant in amateur equipment.

Yes the AF systems currently being offered for medium format are primitive first generation. Nothing close to what is available in 35mm. The mfg's are sticking their toes in the water to see if this one will fly. To offset the cost of AF they have cheapened the rest of the camera considerably. Anyone considering AF medium format should wait for better equipment from what I have seen so far. The current offerings are aimed more for the advanced amateur market to those buying their first medium format camera not knowing any better they will bite on this one.

Due to the cost and lower volumes they should be shooting for less expensive focus confirmation indicators rather than full on auto focus. This would be very useful for low light focusing rather than auto focus would be any way and less expensive to produce.

>Just my perspective.
>
>
>Regards,
>
>Tim
>Classic Photography
>http://www.classicphoto.net

Best regards,

geoff/camera tech
2308 Taraval St. S.F.,CA 94116 USA
UNDERWATER PHOTO/VIDEO SALES-REPAIRS-RENTALS
Bronica western regional factory service center
(415)242-1700 Fax (415)242-1719
email: info@cameratech.com web site: http://www.cameratech.com

Date: Tue, 11 Apr 2000
From: "Malcolm Daly" mdaly@trango.com
Newsgroups: rec.photo.equipment.35mm,rec.photo.technique.nature,rec.climbing
Subject: Re: High Altitude Photo Tips/Equipment?

Don't do it!!! I've got an N90, and Olympus XA and a Nikon FM. When I go to desperate places I always take the XA or the FM depending on space and weight. The N90 (and I think the 60 & 70) has lots of small buttons that are impossible to work with mittens or even gloves on, the AF can seize up at weird times and they suck batteries.

Go light and simple. Learn to adjust the meter based on what your eye and experience tells you and go for it.

BTW, the N90, 70 and 60 are great cameras but they're not designed for high-altitude mountaineering and inclement weather situations.

Cheers!
Malcolm

....

> A few questions re: high altitude (20,000ft +)/climbing
> photography:
>
> 1) I'm upgrading to a new (Nikon) AF body. It's between
>    the N60/N70. For my purposes, the only significant
>    difference I can see between the two is the spot-meter
>    on the N70. Is this a useful feature for mountaineering
>    photos where you may have a subject framed by bright
>    snow/ice/sky, or do the modern matrix or center-weighted
>    metering systems do ok in this type of situation? Any
>    other comments on these bodies for this application? I'm
>    leaning towards the N60 because it's smaller and cheaper
>    (it's about the same weight as the N70).

[Ed. note: see also Mirror Lockup Pages]
Date: Mon, 11 Oct 1999
From: Dan Marder dmarder@frontiernet.net
To: rmonagha@post.cis.smu.edu
Subject: Re: Autofocus problems

Bob,

My findings parallel yours exactly. I use mostly Canon FD equipment, but also some EOS. After becoming dissatisfied with my autofocus results I did some controlled testing, and found that I could consistently get about 100 lp/mm on film from the FD lenses, but only about half that with autofocus. Manual focus of a known-to-be-sharp AF lens (on an A2E body) only improved the situation slightly.

Question: do you know whether the microprism and/or split image screens available for cameras like the Canon EOS 1n restore "real" manual focusing quality, or are they inherently limited by their brightness requirement? My benchmark is the original (mechanical, 1975) Canon F1n.

Another battle I'm currently fighting is blurring due to mirror impact. After a round of disappointing results with an 80-200 f/4 L lens on a Canon T90, I again did some controlled testing. The results were shocking (pun?) and dismaying. With the mirror locked up (on the F1n) and at 1/250 sec, I could get 88+ lp/mm at 200mm. Without locking the mirror, the results dropped to less than 50 lp/mm by 1/60 sec (and decreased at slower speeds).

And this is with a Gitzo 1228/Foba/Arca. My disappointing results have been explained, but the solution isn't obvious: only my oldest camera (the F1n) has MLU capability, but it's devoid of modern metering features. And newer cameras with MLU can't be focused.

I'd appreciate any insights you have wrt this situation.

Dan

From Contax Mailing List;
Date: Fri, 14 Apr 2000
From: "Bob Shell" bob@bobshell.com
Subject: Re: [CONTAX] 645 flash

If you mean in medium format, no rumors right now. Rollei is putting all their resources into getting their new digital SLRs on the market right now. Maybe once that project is finished they will put money toward an AF medium format camera. I know of one new medium format AF camera coming at photokina, but it isn't from Rollei and I can't tell you details yet.

Bob

From: Bo-Ming Tong bmtong@cs.ubc.ca
Date: Mon, 07 Jun 1999
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF lenses the devil?

>    s_hutter@email.com  wrote:
> Not entirely true. The way the lens is put together also affect
> sharpness. Most AF lenses are litterally more loose in construction in
> order to boost AF speed. If you shake an AF lens you can often hear the
> lensgroup moving making a rattling sound. With the small tolerances in
> lenses this indeed compromise sharpness.

Went to a camera shop today and played with an old Minolta 9000. Nice, bright finder. Put same lens on a newer 9xi, the finder is darker ! As for the lens itself, 28-135/4-4.5 AF, it is built of metal, very heavy, nothing can move a bit in the mechanism. Looking back at many of the AF lenses I own or used to own, some of them are so loose that I wonder how the optical axis could be in proper alignment at all. It is not an issue of AF vs MF. It is a question of how you would construct a lens given a specific cost.

--
Bo-Ming Tong http://www.cs.ubc.ca/spider/bmtong/

From: hrphoto@aol.com (HRphoto)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF lenses the devil?
Date: 7 Jun 1999

>The way the lens is put together also affect
>> sharpness. Most AF lenses are litterally more loose in construction in
>> order to boost AF speed. If you shake an AF lens you can often hear the
>> lensgroup moving making a rattling sound. With the small >tolerances in
>> lenses this indeed compromise sharpness.

In the years prior to autofocus, nobody would have accepted any lens, not even the cheapest third party lenses, if they had been as loose as most autofocus lenses are now. It would have been looked upon as an unacceptable flaw. It seems that the convenience of autofocus increases acceptance of mechanically flawed equipment.

Heinz
HRphotography
http://hometown.aol.com/hrphoto/myhomepage/index.html

From: "Brad The Dog" nobody@home.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF lenses the devil?
Date: Mon, 7 Jun 1999

>In the years prior to autofocus, nobody would have accepted any lens, not even
>the cheapest third party lenses, if they had been as loose as most autofocus
>lenses are now.  It would have been looked upon as an unacceptable flaw. It
>seems that the convenience of autofocus increases acceptance of  mechanically
>flawed equipment.

I am not sure looseness is a serious mechanical flaw, or even inferiority. The more technology that is in the lens seems to not require the precision that is required in a manual focus lens. I have some rather loose AF Lenses for my f5 that are equal in quality to some of my old precision tight lenses on my f2. I will admit though for durabilty I would give hands down favorite to a tight manual lens.

From Nikon Mailing List;
Date: Tue, 18 Apr 2000
From: D Bay dbhobby@hfx.andara.com
Subject: [NIKON] Re:Autofocus vs manual focus lenses on FM2

....

In addition to the variables you've already mentioned in your post, keep in mind that most of today's AF lenses do not have depth of field scales printed on them--something that I sorely miss. Of course the FM2 has a mechanical DOF button, but I often find the viewfinder too dark at f/11 or f/16 to tell if both my desired near and far focal points are in focus.

Dennis in Halifax.

From Nikon Mailing List:
Date: Fri, 21 Apr 2000
From: "Joel House" joelhouse@hotmail.com
Subject: [NIKON] AF Accuracy

Just how accurate should I expect my F100 and N90s to be when using Auto Focus? I have several AF lenses that I have tested with an older Nikon F3 that are pretty darn sharp when manually focused. Auto Focus just does not seem to get it. This is especially true of my fast lenses. Stopped down a couple of stops and there is enough depth of field to compensate for focusing errors.

I read an article recently that suggested that you go to a camera store and put a microprism screen in an F5 and have it AF and then check the focus with the microprism. The article suggested that the F5 would be way off. That seems to be the case with my two F100's and N90s.

Before anyone gets all bent out of shape. I always test my lens wide open, down one, two and three stops. I also test the lens in AF and Manual mode using known good equipment. That tells me the limitation of my equipment. I know the limitations of my lenses.

What has your experience been with Nikon Auto Focus and wide open lenses?

From Nikon Mailing List;
Date: Fri, 21 Apr 2000
From: "David Parmet" dparmet@bestweb.net
Subject: Re: [NIKON] AF Accuracy

>Just how accurate should I expect my F100 and N90s to be when 
>using Auto Focus?

Not very accurate, which is why I mostly focus myself when using my N90s. Unless the object in question is clearly defined from the background contrast-wise, AF usually doesn't get it.

david@parmet.net
http://www.parmet.net

From Nikon Mailing List;
Date: Fri, 21 Apr 2000
From: "Curfman, Donald (GEIS)" Donald.Curfman@geis.ge.com
Subject: [NIKON] RE: AF Accuracy

> Just how accurate should I expect my F100 and N90s
> to be when using Auto Focus?

My F4s and F5 are both dead-on accurate, but sometimes I can't make them focus on what I want them to.

> I read an article recently that suggested that you
> go to a camera store and put a microprism screen in
> an F5 and have it AF and then check the focus with
> the microprism. The article suggested that the F5
> would be way off.

They'll focus on the closest part of whatever is under the sensor. If you point it at a person's face, it'll focus on the tip of their nose. If you put the brackets over one eye, it'll focus on the eyebrow.

Bleh.

If you're gonna shoot fast lenses wide open, you'll probably want to get a good screen so you can check on the camera and focus manually if/when you need to.

I put an H2 in my F4s and it really helps. Unfortunately it also totally screws up DOF preview.

Ah well, such is life.

- -Don

[Ed. note: Mr. Shell is a noted photographer, editor of shutterbug magazine, and longtime industry observer...]
Date: Fri, 28 Apr 2000
From: "Bob Shell" bob@bobshell.com
Subject: Re: [CONTAX] Contax SLR range

Somewhere in one of my filing cabinets I have the lavish brochure Olympus gave out that year. They had a big display about the eye control for autofocus, and some actual demos of the system. Their version let you look anywhere on the image field and it would focus there instantly. They implied that products using this system would be forthcoming very soon. Then nothing at all happened, and at the next photokina two years later there was no mention of this at all, and they seemed upset if you asked about it. We'll probably never know what happened internally.

Leitz showed working prototypes of an autofocus system called Correfot at photokina. This must have been in the 70s because they built it on a Leicaflex SL2. The camera was linked by a cable to a box about the size of an early "tower" PC which had all the electronics on breadboards. It worked, but was pretty slow even by the standards of the first Maxxum. Rather than develop the system Leitz chose to license the technology, and I understand that most makers of autofocus SLR cameras still pay them a royalty on some of the technology.

Leica's system used phase matching from two samples from the lens's exit pupil, the same system used in autofocus SLRs today. However the first working prototype of an autofocus camera was not an SLR. It was a camera shown at photokina by Canon in 1968, and was a sort of twin lens camera with the photo taken through one lens and the autofocus sensor viewing through the other. When they showed it at photokina they announced that a production model was about two years away. They were certainly wrong about that!!!!

Bob

....

[Ed.note: the above history is mainly to point out how old autofocus concept is, and the problems with bringing it to market etc.]

From Contax Mailing List:
Date: Tue, 09 May 2000
From: "Bob Shell" bob@bobshell.com
Subject: Re: [CONTAX] rumor

I use AF cameras when I want to work fast. I use manual focus cameras when I am not in a hurry. Contrary to your experience, in my case I find that AF frees me to think more about composition.

Here is my method of AF working. I find the place on the subject where I want my focus, let the camera autofocus there, and then switch the AF off. As long as I don't move forward or back and my subject doesn't either I can just forget about focus and work on composition.

When using the Contax AX I set it so the AF is activated by the thumb button and just follow the above procedure only refocusing if I move or my subject moves. Same with the G series and 645.

You usually don't need to focus for every single frame.

Bob

.....

rec.photo.technique.nature
From: "W Scott Elliot" selliot@direct.ca
[1] Re: Autofocus at f/8? EOS3 vs NikonF100
Date: Sun May 28 2000

I have an EOS 3 and it will auto-focus with a Sigma 400/5.6 and Tamron 1.4 Pro teleconverter in good light. On some subjects or dim light it will not auto focus. I can't imagine why an F 100 wouldn't be able to do the same.

With the Canon L 400/5.6 and matched Canon teleconverter the EOS 3 will only auto-focus using the centre auto focus point. I don't have this combination, but imagine it is more reliable in low light conditions. I should try selecting just the centre AF point with the Sigma/Tamron combination some time to see if it improves reliable performance in poor light.

Scott Elliot

http://mypage.direct.ca/s/selliot

Michael Volow mvolo@duke.edu wrote

> Can either the Canon EOS3? or the Nikon F100 autofocus with an effective
> aperature of f/ 8? For example, a 400/f5.6 lens plus a 1.4x teleconverter? I
> have heard rumors about the EOS3 autofocussing at f/8.

rec.photo.technique.nature
From: "Norm normsmith@worldnet.att.net
[1] Re: Autofocus at f/8? EOS3 vs NikonF100
Date: Sun May 28 2000

According to Canon, the reason the EOS3 will autofocus at f:8 is because they have a new auto focus optical system using a single secondary image-formation lens designed that suffers no peripheral loss due to lens vignetting. I doubt that the Nikon F100 has a similar system.

--
Norm Smith

[Ed. note: Mr. Brick is a well known photo expert, engineer, and contributor to the Leica Mailing list and other photo resource groups...]
From Leica Mailing List:
Date: Wed, 17 May 2000
From: Jim Brick jimbrick@photoaccess.com
Subject: [Leica] Re: Re: AF

As an engineer, and currently (at this very moment) working on autofocus algorithms and having to, via light sensors, read some portion of an image and attempt to focus there via mathematical algorithm, I can attest to the fact that AF will not and can not focus on "anything" you choose to have it focus on. It does not have human cognitive powers. It therefore cannot recognize when a specific part of a flat plain, smooth surface, or as I said before, verticals or horizontals depending upon which way the autofocus sensor is positioned, is in focus.

Pete, if you know how to make AF focus on otherwise unfocusable areas, please call me. We all need to get together for lunch one of these days anyway.

Funny story... When the Contax MF autofocus camera came out, I was in KSP. The manager was showing me how all of the features worked. I pointed it at a Plexiglass magazine holder - side view - (it holds View Camera magazine) and pushed the button. The camera focus started hunting... I thought it was going to work itself into a lather. We could never get it to focus on the Plexiglass rack. Of course it was quite simple manually. You could focus on any part of the edge of the Plexiglass that you wished. Totally impossible with AF. To be fare, these cameras are mostly sold to wedding photographers and are not used for product photography while in the AF mode.

Jim

Pete Su wrote:

>It is no harder to use AF to focus on a specific part of the scene than it is
>to use the leica rangefinder,  or the split image circle rangefinder on a
>focusing screen to achieve the same thing. You tell the camera to use just the
>single center AF sensor, then you use this sensor like a rangefinder. I do this
>all the time with my pathetic old Nikon 8008s, and it works. It even works
>pretty well in low light, when I have a hard time confirming focus visually.
>And this is a 10 or 15 year old camera. The new sensors are a lot better.
>
>With SLRs, you can also confirm the focus visually, something that you can't do
>with the Leica RF.
>
>If people are going to complain about the alleged "loss of control" with an AF
>camera, then they should be worrying about exactly the same loss in the Leica
>M.
>
>Pete

From Pentax Mailing List:
From: FirstEgg@aol.com
Date: Mon, 12 Jun 2000
Subject: Re: Will a modern autofocus lens work with Pentax SF-1 Autofocus

ma0934@hotmail.com writes:

>  Do you know if a modern "Sigma 28-200 autofocus lens for Pentax" (works fine
> with ZX-5n & PZ-1p) will work with a Pentax SF-1 Autofocus camera?

Generally speaking, Sigma's backwards/forwards compatibility leaves something to be desired. Most lenses for the PZ/Z series don't work with the SF series bodies. I would not buy one sight unseen without either the ability to return it without hassle, or test a specific one at a local shop. I had the experience with a PZ10, PZ70 and my SF1 at a local shop. The shop thought there was a problem with my camera, but all the PENTAX brand AF lenses were fine, and all the Tamron AF', too. Specific Sigmas were fine on the PZ10 & 70, but would not autofocus or give focus confirmation on my SF1.

Tom D

From Nikon Mailing List:
Date: Sun, 11 Jun 2000
From: Uweflammer@aol.com
Subject: Re: [NIKON] Fw: F100 doesn't recognise AF lenses - help!

> My F100 seems to have developed a weird problem: it doesn't
> recognise my AF lenses as AF lenses, but treats them like AI
> lenses. So no AF, no aperture shown (just F--) etc. The camera
> still meters and fires.

Follow up (next morning). I switched the camera on and everything seems to have returned to normal. I checked it with all lenses (AF 24-50, AF 70-210 and AF Micro 105) and it shows the aperture again and it performs AF again. Nevertheless, I still wondering why this is happening and what

I can do to prevent it.

Typical problem of today's electronics. Basically, all these electronic gadgets are nice and helpful. AF and 3-D-Matrix metering make photography much easier, but only as long as they are working correctly.

What you can do? Ckeckout the problem some days more, write down an exact report, what happend and under which conditions. Then, before you send in your camera for repair, call your local Nikon sevice office by phone, may be they can give you some advice before. After you have sended it in, you only can hope - may be the camera shows this problem immediately after they unpacked it, so that they must look for it, or may be there is an experienced repairman who really wants to help his customers and examines your camera long enough to find out something. But it is also possible that they unpack your camera, check it one time, find it in good working order and send it back to you. Then you have to go on using it until the electronics break down completely.

I am working as a controls engineer in industrial automation, and often, i am running into similar problems. Today's electronics are so complicated that even experienced servicemen cannot understand them completely. Often you have to exchange all the suspicious electronic control stuff, it may be broken or not, and then to pray that it will work, and keep on working after you left your customer. Finally, after you worked long enough on some product, got enough experience to understand it, it will be discontinued because it lacks the newest gadgets. And the nightmare starts again.

I do photography as a hobby, for recreation. And i enjoy my easy-to-understand old-fashioned Nikon FM, F2 and F3, equipped with AI lenses.

Best regards
Uwe

From Contax Mailing List:
Date: Sat, 10 Jun 2000
From: "Bob Shell" bob@bobshell.com
Subject: Re: [CONTAX] New camera soon

High end APS is just about dead. They're still engraving the tombstone. Nikon has already discontinued most of the lenses they introduced last year with the Pronea S. Minolta doesn't even talk about their APS SLR. I doubt you will see any more SLR cameras using APS. It will live on in point and shoot and single use cameras.

Bob

....

[Ed. note: besides being a noted photographer and lens expert, Mr. Brick is also an engineer designing AF systems..]
From Leica Mailing List:
Date: Tue, 16 May 2000
From: Jim Brick jimbrick@photoaccess.com
Subject: [Leica] Re: AF

Rich Lahrson wrote:

>Mark Rabiner wrote:
>> What if you had to take a picture of a chair?
>
>Hi Mark,
>
>     You focuz a third in.
>
>                               Rich

Not usually easy to do with autofocus. This is the problem with AF. It is difficult to tell it "exactly" where to focus. I can only focus on something that has an abrupt change in contrast. It may not be able to see vertical lines, or horizontal lines. A photograph of that diminishing picket fence might be difficult. Or that photograph of the diminishing railroad track. Or that chair with vertical slats. AF is great for wedding receptions, bachelor parties, a two year old, a dinner party, etc.

But it sucks big time if you know the "craft" of photography and want to focus on a "specific" spot because that will give you the precise DOF that you want. In fifty years, I've not yet found a use for AF. I personally like to control my photographic result. I don't want a computer algorithm dreamed up by some programmer sitting in a cubicle, to attempt to focus for me.

Having said that, that is precisely what I am doing at this moment. I'm writing the algorithm and program to focus the digital camera we (PhotoAccess) are designing and producing. But I won't use it. Engineering it is one thing. Using it is yet another.

Jim

[Ed. note: Dr. Wall publishes the giant Photography FAQ...]
From Nikon MF Mailing List:
Date: Wed, 31 May 2000
From: John Wall john_wall@ncsu.edu
Subject: New Nikon Full Line Product Guide Now Out

Folks --

Just picked up at my local shop Volume 6 of the Nikon Full Line Product Guide, published by Nikon USA. They got their copies yesterday.

This is a must-have for all of us.

The front cover has a snow boarder going off a mountain (shot with an F4!). The work has 136 pages plus the covers. Lists the D1, F5, F100, N80, and N60, along with the N90s, the F3, the FM2 and the FM10.

The future is clear -- lots on digital. And the list of manual focus lenses in the current line is down to 17 models + the 4 manual TCs, down from 29 models listed in Volume 5.

They are: the 18 f3.5, 24 f2, 28 f2, 35 f1.4 -- 85 f1.4, 105 f1.8, 105 f2.5, 135 f2.8, 500 f4 --500 f8, 1000 f11, 35-200 f 3.5-4.5, 50-300 f4.5, 180-600 f8, PC 28, PC Micro 85 f/2.8 (a ringer -- this is the new T/S lens), 200 micro plus the TC 14A & B, TC 201, and TC 301

The VR lens is not listed, nor is the 14 mm lens that was just announced.

Check it out.

Best,

NikonJohn

From Rollei Mailing List:
Date: Thu, 22 Jun 2000
From: ARTHURWG@aol.com
Subject: Re: [Rollei] 6008i exposure accuracy

I found the main problem with the Contax 645 was that the AF seemed to hunt and was difficult to focus in low light. If the AF's not Nikon fast, you might as well focus manually. Now the Mamiya 645 AF..... After much thought I went for the 6008i; so far so good. Arthur

[Ed. note: Rollei 6008i is a manual focus medium format SLR...]

From Nikon MF Mailing List:
Date: Sun, 18 Jun 2000
From: Paul DiBiase paulcanada1@yahoo.com
Subject: Re: AF Lenses on MF Bodies

While the auto focus lenses will manual focus, keep in mind that some of them have an awful feel while manually focusing. The inexpensive consumer, plastic lenses such as my 35-80mm zoom are a good example. First, let me state for the record I find this lens to be very sharp and capable of delivering high quality images. But the focus feel is very poor. The focusing ring is small and the slightest bump or knock will cause the ring to turn and shift the focus. Focus has to be checked before every frame even if the camera is mounted on a firm tripod and nothing has been touched. On the other hand the more expensive autofocus glass also has a good focusing feel and does not exhibit this problem.

=====
Owner of the Pacific Northwest Photography E-mail list at http://www.egroups.com/group/pnwphoto

[Ed. note: as expected, larger medium format AF is bigger, slower, and "eats" more batteries...]
From Leica (Topica) Mailing List:
Date: Mon, 26 Jun 2000
From: ARTHURWG@aol.com
Subject: Re: In defence of (some) Nikkors vs Leica glass (was 'horriblemistake')

I found the Contax 645 AF slow and unsure, not really fast enough for street photography. It's also one of the heaviest battery users ever. Optics are great, however.

Arthur

From Leica (Topica) Mailing List:
Date: Mon, 26 Jun 2000
From: InfinityDT@aol.com
Subject: Re: In defence of (some) Nikkors vs Leica glass (was 'horriblemistake')

ewelch@flashcom.net writes:

If I were to move to an AF-SLR, it just might be a Contax 645! I'm hearing good things about that camera.

This is pretty far off-topic, so I'll keep it really short. I've tried out all 3 6x4.5 AF SLRs and they're pretty much on a par with where 35mm AF SLRs were ten years ago. They're great for those who have eyesight trouble focusing, but rollfilm just isn't the format to take full advantage of AF technology (predictive software and high-speed framing rates).

[Ed. note: Mr. Brick is a noted engineer developing AF systems software etc.]
From Leica (Topica) Mailing LIst:
Date: Mon, 26 Jun 2000
From: Jim Brick jimbrick@photoaccess.com
Subject: AF

Arthurwg@aol.com wrote:

>My Nikon  F100's AF is fast enough for Street photography. Arthur

The problem with AF and "street" photography is that what YOU want to focus on and what the CAMERA wants to focus on are usually two different things. Especially at wide apertures.

Of course, this is the problem with AF for lots of other subjects as well. AF works well for isolated subjects and small apertures with subject contrast lines running in the proper direction. The proper direction for that manufacturer's AF sensor set-up.

I don't own a Contax 645 but I have played with it a lot. It is easy to get it into a situation where the focus starts hunting and never stops unless you point the camera somewhere else.

I'll do the focusing myself, thank you, which is why I have Leica and Hasselblad, (and 4x5). All manual focus.

I can see uses for AF. You are in a dense jungle and a tiger is running straight at you from 30m away. The tiger is centered in the viewfinder. The stripes around the eyes make a good AF subject. Motor drive whirring, a whole roll in focus.

Chomp!

Was that George Lepp?

Jim

From Leica (Topica) List:
Date: Tue, 27 Jun 2000
From: Rick Dykstra rdandcb@cybermac.com.au
Subject: Re: AF

Godfrey DiGiorgi wrote:

>  I find the focus
> hunting not under my direct control disorienting.

Hi Godfrey. How're you getting on with your SF20? I'm very happy with mine.

As for focus hunting, I've got an F5 and I lose about one shot a roll through the thing going off on a wobbly adventure just as I'm pressing the shutter. The spectators standing nearby wonder what's made me swear when it happens. The lens really goes beserk, shuddering back and forth.

But to be fair, I get so many shots with my F5 I'd never get with a manual focus SLR. Of the full frame running flat out kind. I do also miss some shots I would get with a familiar manual camera. It's all about compromises, this photography game.

Regards

Rick Dykstra

From Pentax Mailing List:
Date: Wed, 28 Jun 2000
From: Bill Johnson camerabill@yahoo.com
Subject: Medium Format autofocus performance

Hi,

Stopped by a local camera store today and played with the new Contax 645 AF (sadly, they don't carry Pentax). The camera seemed well built, solid and balanced nicely, but I was very underwhelmed by the AF performance. The lens was the 80 f/2 planar, and the store was well lit with substantial light coming in from outside also. Anyway, there was considerable lag between pushing the AF start button (with the rear control) and the AF activating. Furthermore, in actual focusing, I found it slow going from reasonably close (around 3 feet) to approximately 30 feet. It has a 3 point AF sensor, and boy, did it hunt! I mean, if I had one point on a subject at one distance, and another point at another distance, it would juggle the two and never achieve focus. I know that this can be a problem with other multipoint af systems, but I have never experienced where it would go back and forth, continually, until you pointed the camera away or turned off the AF.

My reference point as to the speed of the Contax AF is a Pentax ZX-5n with FA 50 f/1.4, which I have found (in my limited experience with Pentax AF lenses) to be on the slow side for AF itself. However, there is no comparison to the Contax, the 5n completely blows it away. Maybe comparing 35mm to medium format is a bit unfair, and the 80mm planar is a good sized piece of glass, but the AF motor is in the lens (like Canon) and it would seem that they could put a fair sized motor in a fair sized lens like that.

So.... here is my question. (I know, cut to the chase) I am thinking about splurging on the Pentax 645 AF (you didn't really think I was going to get the Contax did you?) but I am wondering:

1. Has anyone compared it's AF head to head with the Contax and if so, what are you thoughts?

2. Can anyone tell me how the Pentax 645 AF compares to the ZX-5n?

Sorry about the long winded post, and yes I asked the clerk and they had just put new batteries in the camera. Looking forward to everyone's wisdom.

William in Utah.

From Nikon MF Mailing List;
Date: Fri, 30 Jun 2000
From: "Rolland Elliott" rolland_elliott@yahoo.com
Subject: Nikon officially dumps almost 50% of the Manual Focus lenses

Pay your respects to the following victims:

8mm f/2.8
15mm f/3.5
50mm f/1.2
200mm f/2
400mm f/2.8
400mm f/3.5
400mm f/5.6
600mm f/5.6
800mm f/5.6
2000mm f/11
1200-1700mm f/5.6-8 (like anyone would really buy this lens anyways)
UV 105mm f/4.5

The above lenses are sadly MIS (missing in action) from Nikon's latest volume 6 of the full line product guide.

Would someone on this list please do me a favor and go after the idiot in Nikon's marketing dept. that decided to dump almost 50% of Nikon's MF line and introduce cameras like the N80 which don't even meter with MF lenses and uses IR film advance mechanisms? Argh!

Peace, Rolland

From: pburian@aol.com (PBurian)
Newsgroups: rec.photo.technique.nature
Date: 09 Jun 2000
Subject: Re: Autofocus at f/8? EOS3 vs NikonF100

>I have an EOS 3 and it will auto-focus with a Sigma 400/5.6 and Tamron 1.4
>Pro teleconverter in good light.  On some subjects or dim light it will not
>auto focus.  I can't imagine why an F 100 wouldn't be able to do the same.

Most cameras of ALL brands are designed not to autofocus when the lens + converter produces an effective aperture smaller than f/5.6. But....

When you use an aftermarket lens or converter, sometimes they DO try to autofocus. Depends on the brand of converter. Naturally, AF is lousy when the sensors are getting so little light. (That's why camera manufacturers don't want the cameras to try to AF with such equipment.)

The EOS-3 and EOS-1v are the only cameras so far that ARE intended to AF even with an f/8 combination. With the central AF sensor only -- all sensitivity is there and the sensor is very dense, with numerous pixels so it works. Not great but ok.

Peter Burian

From: David Littlewood david@demon.co.uk
Newsgroups: rec.photo.equipment.35mm,rec.photo.misc
Date: Mon, 12 Jun 2000
Subject: Re: Best AutoFocus

Tony Spadaro aspadaroas@post.com writes

>  The IS L lenses can Pan, and even work on Tripods. It's only
>the simplest consumer IS lenses that cannot pan. I've been
>looking at the new 300mm f4 USM IS (not sure whether it's an "L"
>or not) It has single or double direction IS so it can be used
>to Pan. There is not enough information to know if it will work
>from a tripod yet though.

Just to add to what Tony said, as I understand it from the Canon literature, the panning mode ("mode 2") on L lenses simply involves deactivating the IS in the horizontal plane and leaving it operating for the vertical - so the lens does not tie itself in knots trying to undo the pan.

It's not as if it would be very expensive to deactivate the horizontal IS, but I suppose for "consumer" level products a dollar or so is too much waste. You can at least switch it off, even on the cheaper lenses.

--

David Littlewood

[Ed. note: another way to use manual lenses on AF bodies - in AF modes - without obsoleting your investment - why can't other OEMs do this? ;-)]
From Pentax Mailing List:
Date: 12 Jul 2000
From: "Stephen Graham" stephen.graham@scotland.com
Subject: Re:AF adaptor

darrylchew darrylchew@pacific.net.sg wrote:

>any comments on the pentax 1.7X af converter. brand new at USD$90

It's worth it for that cash but it's a little different from normal teleconverters in that it converts manual focus lenses into AF ones! Used with a MF 50mm prime you get a nice 85mm AF portrait lens.

Having said that I've got one but don't find a lot of use for it.

Regards
Stephen R. Graham
stephen.graham@scotland.com

From: "adas" adwrobel@pol.pl
Newsgroups: rec.photo.equipment.35mm
Date: Mon, 3 Jul 2000
Subject: Re: autofocus

U+ytkownik Rwyzaz rwyzaz@aol.com said

> I am using a Nikon autofocus camera. I notice that with two different lenses,
> one nikin and one tamron, that the focus does not remain constant when zooming
> from one end to the other of the scale. In both instances the camera focuses
> the lens too close at wider angles. It is not just a matter of the viewfinder
> image. The setting moves from infinity to 30 feet. Any focal length less than
> 50mm and sometimes 70mm results in focus change. Is the fault in the camera? or
> is this the way it is with autofocus zoom lenses?

It is nothing wrong.
Popular "ZOOMS" are not _true zooms_
they are only vari-focal, that means that focus does not remain constant

only "TRUE ZOOMS" (like in cinema cameras) can do that

adam

From: "Uncle Spam" unclespam@spam.spam.spam.spam.net
Newsgroups: rec.photo.equipment.35mm
Date: Wed, 05 Jul 2000
Subject: Re: Autofocus Question

>I keep reading that autofocus cameras, specifically Canon A2s, won't
>autofocus below (smaller) than f5.6.  Does this mean that if the maximum
>variable aperture is f4-5.6 and I stop down to f11, I have a problem? (I
>haven't noticed one.)  Or is that ok?  I'm really new to this autofocus
>stuff, and I'd appreciate any help I can get.
>Also, does a red 25 or 29 affect the camera/lens ability to autofocus?
>Thank for any help!

The camera does its autofocusing through the lens at its full aperture, so setting a smaller aperture such as f/11 doesn't make any difference -- the lens doesn't actually stop down to f/11 until just before the shutter fires, and the AF system has done its job by then. Ditto with the red 25 or 29, which are indications from the meter system and don't have anything to do with the autofocusing.

Incidentally, the reason the camera won't autofocus with lenses having a smaller maximum aperture than f/5.6 doesn't have anything to do with the image brightness or the aperture to which you've set the camera for making the actual picture. The AF sensors work by capturing rays from the opposite edges of the "exit pupil" of the lens (the exit pupil is the hole the light comes through, as seen from the back) and comparing them. If the lens' maximum aperture is smaller than f/5.6, its exit pupil is too small and the rays don't come through it at the proper angle to reach the AF sensors. That's why the AF won't work at smaller apertures (such as f/8 or f/11) even if you're trying to autofocus on something that's really, really bright.

From: Robert Krawitz rlk@alum.mit.edu
Newsgroups: rec.photo.equipment.35mm
Date: 05 Jul 2000
Subject: Re: Autofocus Question

Skip shadowcatcher@home.com writes:

> I was concerned that the red filters would change the wave lengths of
> the infrared that the sensors emit, thus changing the information that
> the camera receives.  I'll just have to try it, and see.

Very few (if any at all) SLR's use active AF (where the camera emits one or more infrared beams and uses a rangefinder-type system to measure the distance to the nearest reflective object). That's confined to point & shoots. SLR's use passive AF, where the camera uses the light coming in through the lens. Many SLR's have an AF assist light, but it's used very differently than the IR beams that active AF systems used. The AF assist is used to illuminate the subject, and in some cases to provide a patterned illumination that creates contrast needed for the AF to function.

--

Robert Krawitz http://www.tiac.net/users/rlk/

From: Tony Spadaro aspadaroas@post.com
Date: Sun, 09 Jul 2000
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Autofocus Question

Because the AF sensors have to be a distance apart to work. If the max aperture of the lens is less than that distance they can not work no matter how much light is coming in. They are actually no longer recieving signal. The reason the EOS 3 (and I assume the EOS IV also) can do AF at f 8 is because the sensors are set closer together. As time goes on I'm sure eventually cameras will all be able to AF at f11 or even 16.

From: smitbret smitbret@isu.edu
Newsgroups: rec.photo.equipment.35mm
Date: Wed, 05 Jul 2000
Subject: Re: Autofocus Question

The camera won't stop down until you actually take the picture, so as long as the maximum aperture is 5.6 or better you should have no problem if there is enough light. Although, many 3rd party lenses will AF at less than f5.6, (Sigma has two or three f6.3 lenses). Adding a filter (red or otherwise) will affect ability to AF. Using a filter changes the effective aperture, and should be considered.

It's not just the A2, it's most AF cameras with the exception of Canon's EOS 3 and 1V, because they use a CMOS system that is different than other AF bodies from Canon, Nikon, Minolta, Pentax, etc. F5.6 is the rule rather than the exception.

-Brett

...

From: Robert Krawitz rlk@alum.mit.edu
Newsgroups: rec.photo.equipment.35mm
Date: 05 Jul 2000
Subject: Re: Autofocus Question

smitbret smitbret@isu.edu writes:

> Adding a filter (red or otherwise) will affect ability to AF.  Using a
> filter changes the effective aperture, and should be considered.

It reduces the amount of light coming through the lens, and can change the aperture chosen in shutter priority mode, but it doesn't change the effective maximum aperture of the lens, which is what matters. Of course, if it reduces the amount of light or contrast too much, that will affect AF operation.

--

Robert Krawitz rlk@alum.mit.edu

[Ed. note: obsolete AF lenses already? Got a handheld meter? ;-)]
From: "edb" kawijet69@hotmail.com
Newsgroups: rec.photo.equipment.35mm,rec.photo.misc
Date: Wed, 12 Jul 2000
Subject: Re: AF vs. Manual focus lenses for Nikon FE

You guys looking to use older lenses better check the spec for the N80. I just got one and also have an FE with an MD12 for B/WE (since acquiring the N80) and all the stuff I've read and tried with my lenses pretty much lead me to believe that the 80 is NOT backward compatible with a lot of lenses with respect to the metering system. Book says they have to be "CPU" type lenses to use AE functionality of the body. Pop Photography said it in July issue "review" too that AI and AI-so lenses wouldn't work with onboard meter. Sorry if that is old news to everybody, and I know the topic was autofocus...you guys probably actually have handheld meters anyway.

The FE is a great camera, I didn't want to trade it so I just took the plunge and got the body and 2 "starter" Tamron zooms (28-80 & 80-210) to cover the 28-200mm (5 different lenses) that I had been using with my FE. I love the N80 but then again I am it's target audience, the somewhat serious amateur. I'll upgrade the optics when folks pay me to take pictures ;-) For now, my primary (color film) bag is about 10 pounds lighter...

I find it cool though that this thread has shown that other folks think of an N80/FE combo as good for color/B-W combo, that's sure how I had it figured.

edb

...

[Ed. note: No parts for older AF models?]
From Minolta Mailing List:
Date: Thu, 13 Jul 2000
From: Dawn Weekley dweekley@cityofhuntington.com
Subject: My 3000i won't autofocus

The other night while using my 3000i, it worked fine one picture, then the next, nothing. The autofocus simply stopped working. I can manual focus fine. I changed lenses thinking that may have been the problem, but to no avail. I took the camera to a camera shop here in town and after looking the camera up in the book I was simply told, "Nothing we can do. No parts for it". I was hoping someone out there has either had this fixable problem, or can tell me where to go from here. I know it is an older camera, but I just love it, and can't stand the thought of having to 'get rid of' it.

Thanks!

Dawn

From pentax mailing list:
Date: Tue, 18 Jul 2000
From: Mike Johnston michaeljohnston@ameritech.net
Subject: Re: Contax goes AF

I don't think the list is anti-AF. I myself am not anti-AF. I have just never felt any need for it for what I do.

I personally used AF for years as a pro (3 Nikon 8008s and 1 F4, plus several Canons) but went back to manual focus as soon as I could. I just like being in control of the camera--I like simple controls, non-distracting operation, and instantaneous responsiveness.

I don't really have anything against AF...certainly not for anybody else, if it's their choice. But I definitely prefer manual focus myself.

--Mike

From Pentax Mailing List:
Date: Wed, 19 Jul 2000
From: Alexander Krohe geophysion@yahoo.com
Subject: merits of modern camera systems [was: Contax goes AF]

"I don't think the list is anti-AF."

Hi all,

thanks for your many responses. I find all this difficult to aswer, since the issue seems to be camera quality (or the lack of) rather than the merits of Af and Mf.

E.g. Shel says:
"Thus far every AF lens I've ever used or tried ....were very stiff, others felt loose and seemed, for lack of a better word, wobbly."

This is not generally true. During a trade show last year I tried many lenses. I mentioned the FA 50mm macro, that I have and which is definitly high quality. Another case is the 300mm: In practical use the FA 300mm/4.5 is much easier to handle even when used in MF than the a A*300mm/4 (you have to turn a lot from infinity to the shortest distance). I don't see where the FA is inferior quality (in fact, the contrary is true).

"If one understands exposure, multi-segment metering means nothing,"

There are two approaches for the use of automatic mtering modes: the first is to make camera operation faster - if there is no time to adjust the camera. In this case, for the optimum use of the automatic functions, the same is valid as for the optimum use of the metered manual: you must understand how exposure works and you must understand the metering system. However, there is another approach for the use of automatic: those who don't understand those things will get better picuteres. Don't put this down.

Shel says: "one gives up when using, and depending upon, these "wunderkameras" ...the ability to learn photography and truly understand how light and silver interact and make wonderful images."

I don't think so. It is simply a different way to learn. You also learn nothing only by matching the needle of a K1000. I all cases, you have to think about what you are doing.

Shel says: "[Af-cameras] take longer for the shutter to fire after pressing the release than the manual cameras I've used."

I aggree with this one, particularly if you are used to the the Lx which appears to have an extremely short delay time. The relatively long delay time was one of the biggest surprise when I tried the Eos1n.

Rob Studdert says: "AF lenses do generally require a lesser degree of rotation to get from infinity to the minimum focus point this is to speed up the auto-focus action"

This has disadvantages but also advantages. You are only looking at the disadvantages. A short degree of rotation and easy rotation are, in my view, an advantage for hand held "intuitive" photography (but I agree, this is a disadvantage when shooting from a tripod).

Rob Studdert says: "The AF cameras are great but it is all getting a bit much, the new Contax offers auto focus bracketing and auto exposure bracketing, 9 bracketed shots....."

Sure, there are many features that are not needed by every user. The idea of the PZ1p was to "personalize" the camera by putting those features that you don't need into the background ("custom function"). Once personalized, the PZ1p is an easy to use camera. The advantage is that the camera can be personalized for many differend users with different needs.

John Glover says: "the matte focusing screen [of the PZ-1p] is not really bright enough, nor contrasty enough to do critical manual focusing."

In another forum I was adviced to try a PZ1p screen with the LX because it is brighter than the original LX-screens. I tried this and it is true: PZ1p screens are brighter and less grainy than the original LX screens.

Thanks for reading, Alexander

From: MarkTuccillo markjtuc@megahits.com
Newsgroups: rec.photo.equipment.35mm
Date: Sun, 23 Jul 2000
Subject: Re: Metal versus plastic

Lee wrote:

> What are the pros and cons of using either of these materials? For
> instance, metal expands or contracts according to temperature. How
> does this affect the performance of a camera? Metals are heavier. Is
> there a cost saving to the consumer using plastic? Is it merely a
> psychological issue? I have just bought a plastic EOS 300 - hence my
> query.

Make no mistake about it, plastic is used to save money, and nothing else. Moving up through the Canon line, the amount of plastic decreases and the cost increases, until the all metal EOS 1V.

High end metal bodies are not bent sheet metal, as cameras were made years ago, but die cast high strength aluminum / magnesium alloys. Bodies of this construction, such as the Nikon F5, F100 and EOS 1V, are many times stronger then lower cost plastic bodies. An impact strong enough to dent them would shatter a plastic body.

The thermal expansion of plastic is about 10 times greater then most alloys used in cameras.

The strength of a metal body comes at a cost both in terms of weight and economics, hence it's use only in high end bodies designed to handle extreme conditions. If you baby your bodys, then the all plastic bodys will serve you well.

Mark

From Minolta Mailing List:
Date: Thu, 10 Aug 2000
From: "Karasev, Alexander" alexander.karasev@gs.com
Subject: Re: 1960's MC v. 2000's Maxxum lenses

In some, admittedly, extreme cases one may in fact see a decline in quality from 60's to this day for some lenses as assembly labor becomes more expensive, weight and profit margin requirements necessitate the increased use of plastic, and AF mechanisms requiring less friction necessitate wider gaps which results in play among the elements and imprecise positioning.

The rear elements of my AF 24-50/4 and 85/1.4 have around 1/16" lateral play - in both cases confirmed by Minolta as necessary limitations of design that "do not significantly affect the perceived image quality" (paraphrasing).

That said, there are significant advantages in coating technology that occurred in the 60's through 80's. The modern coatings are both more scratch resistant and more efficient (so long as they're not one of those most recent "bright, colorful" coatings whose rainbow of reflections is sub-optimal but was insisted upon as it actually makes the lenses more attractive looking and sells them better). An optimal coating will have several colors, too - but the reflections are not nearly as bright / spectacular - because the light goes through the lens rather than reflects a (marketable) image towards the observer.

The bottom line, if you compare fixed focal MC Rokkors in the 35-135mm range to Maxxums, you may see little difference in sharpness - however the Maxxums will likely have better contrast and flare resistance.

Do realize that camera bodies have advanced dramatically over these years and the body is what helps you to get the shot - teh lens "only" focuses the light. Rokkor lenses will not work on Maxxum bodies directly. There's an adapter that will compromise image quality (albeit only slightly) and increase the focal length by 10% or so - but even with this adapter you do not get wide-open metering, Maxxum matrix metering or any other advanced mode, or auto aperture operation.

Unless you're talking about an *extensive* collection and / or do not care for any AF, AE, and / or have only $300 to $400 to spend on the whole system, and / or require specifically MC 58/1.2, MD 50/1.2 or MD 135/2.0, I would go with a used Maxxum setup - 600si or 700si, 50/1.7 (or 1.4), 35/2, 135/2.8, etc.

Alex

[Ed.note: nikon has dropped half of its manual focus lenses, the rest are rumored to be from end of production runs; most current cameras can't work without CPUs in the (AF) lenses, and now a new line of Nikon G series lenses will only work on the latest AF cameras due to lack of manual aperture ring controls; is there a trend here? ;-( ]

Date: Wed, 16 Aug 2000
From: Alexander mediadyne@hol.gr
Subject: Re: [NIKON] The End of an Era - was: Nikon New Gear Rumors

you wrote:

> >75-300 G (new series lens) to replace 75-240 lacks aperture control grill
> >and will only work with new cameras , will NOT work with older MF cameras.
>
>
>There was a time when this would have greatly concerned me. Nowadays I\  find
>myself moving from AIS to AI rather than AF. But it does mean THE END of
>one of
>the *great* arguments in favour of the Nikon system, which is upwards
>compatibility of new lenses on older cameras (especially so since downwards
>compatibility in the other direction was neglected).
>
>Mark

I know.

In fact I wanted to avoid to be the one to bring out this part of the news.

I was very saddened when I first heard about it.

It marks a new lens *series*, the G series. An entire line of new lenses that are without aperture grills, and the aperture can be controlled from the modern cameras only, and they can not be used with the old MF cameras.

I almost feel guilty for telling you all, but someone had to do it... Nikon is dropping the axe on MF.

From Nikon Mailing List:
Date: Thu, 17 Aug 2000
From: John Albino jalbino@jwalbino.com
Subject: Re: [NIKON] The end of an era

Gopi Sundaram wrote:

>P.S. I don't like setting the aperture using a command dial. Tried it
>      on the F100, and hated it. I feel your pain.

One of the problems with setting the aperture manually (i.e., using the aperture ring rather than the command dial) is the Minimum Aperture Lock on AF lenses. It far too easily engages if the lens is manually stopped down to minimum aperture, and only a few AF lenses have the ability to lock-out (switch off) the Lock.

Also, variable-aperture zooms are less convenient to use with aperture ring setting.

- --
John Albino
mailto:jalbino@jwalbino.com

[Ed. note - another interesting factoid from Mr. John Albino re: nikon MF lenses...]
From Nikon Mailing List:
Date: Fri, 18 Aug 2000
From: John Albino jalbino@jwalbino.com
Subject: RE: [NIKON] Advantage of Nikon over others (my personal view)

Kho King, Koh wrote:

>Alexander wrote:
>     People who buy F80 and F60/F65 don't care about MF lenses? NO! I care!

But at least you *can* use MF lenses on those cameras. Which makes Nikon unique among AF camera makers.

>     Just to summarize my thought, I think Nikon will not stop the production
>of MF body (FM2 and the replacement of F3hp if there is one...) because
>these bodies can still use AF lenses.

But Nikon is gradually pushing up the price of these cameras to limit demand. I personally believe the F3 has been discontinued from manufacturing, and soon will depart the catalog. There's a good possibility no more FM2s are being made, either, and the increasing price is simply reflecting declining inventory.

>  However, what I believe is that Nikon
>will not support MF lenses in their future cameras and these will make the
>used MF lenses in the market become useless or less important and finally
>disappear...

Yeah, they'll "finally disappear" because people like me will buy them up and get them out of circulation. {grin}

>ps: to verify if Nikon still care about MF lenses is easy, just wait and see
>if there is still new design MF lenses to be announced by Nikon again. When
>is the last time Nikon announced new MF lenses compare to new AF lenses?

I believe the correct answer is "Never." Except for the recently released 85 PC Micro Tilt/Shift lens, Nikon has not announced nor released any new MF lenses since 1985. All lenses since then have been AF only.

- --
John Albino
mailto:jalbino@jwalbino.com

[Ed. note: Nikon's new G series lenses lack manual f/stop diaphragms...]
From Nikon Mailing List:
Date: Wed, 30 Aug 2000
From: Rollin Verlinde Rollin.Verlinde@lin.vlaanderen.be
Subject: Re: [NIKON] Oh G

I 'll never buy a G-lens (at least, I wait as long as possible) because I think the electronic DOF-preview button on modern camera's stinks when you control the diafragm electronicly.

You cannot change f-stops when the button is pressed, so when doing landscapes or macro you see 'bright-dark-bright- darker-bright-verydark' and it does not only annoy me but my eyes get no time to adjust to the dark. Landscapes don 't run away but insects do, so no time to waste.

Solution is to manually turn the diafragm ring. This will be impossible in the future. Unless of course the dof-preview buttons will be altered, but frankly I doubt it.

a slightly dissapointed Rollin

ps : why don't they make lenses in clear plexy, that should be fun ? ;-)

[Ed. note: reminder re: af vs. glass cases in museums, jewelry, zoos..]
From Minolta Mailing List:
Date: Sun, 10 Sep 2000
From: Bill800si@aol.com
Subject: Re: Pictures Through Glass

thecomputerguru@eoni.com writes: shots through the glass?

Mark,

Remember when shooting through the glass not to use your AF (Auto-focus). Use manual focus and choose your DoF (depth of field) carefully.

Later,
Bill B. (USA)

[Ed. note: more on obsoleting manual cameras with new no aperture ring lenses..]
From Nikon Mailing List:
Date: Sat, 2 Sep 2000
From: "Hansen, Lars Holst" LHHansen at zi dot ku dot dk
Subject: RE: Re: New Nikon G mount

Dear all!

It was with great regret I saw that the G-type lens had no aperture ring. At http://www.klt.co.jp/Nikon/Press_Release/nikkor70-300.html it says:"For the F4, F90-series, F70, F-801-series and F-601M cameras, only programmed auto or shutter-priority auto exposure mode can be used. (The lens is not compatible with other cameras.)". I suspect however that even FA (P & S modes) and FG (P mode) can be used. At least if the aperture stop down is mechanically controlled via a stop down lever and not ellectronically controlled (Canon EF-style). Never the less this new lens type will be usable (with constrains) with only a few MF cameras. I was happy to see that the other new AF lenses all had aperture rings;

http://www.klt.co.jp/Nikon/Press_Release/nikkor18-35.html
http://www.klt.co.jp/Nikon/Press_Release/nikkor24-85.html
http://www.klt.co.jp/Nikon/Press_Release/nikkor300.html

I also suspect that the lens mount of this G type lens is of the plastic type. The G type seems to be aimed at the begginer; " The G-type Nikkor lens offers easier, virtually mistake-free operation since the aperture does not need to be set to minimum. The AF Zoom-Nikkor 70-300mm f/4-5.6G lens represents a new level of operational ease for Nikon users--even first-time SLR users."

(from http://www.klt.co.jp/Nikon/Press_Release/nikkor70-300.html)

I could fear that camera dealers will not notify Nikon SLR beginners of the limited backwards compatibility, and that somone will therefore be "trapped". I believe the "mistake-free operation since the aperture does not need to be set to minimum." is just some excuse for the cost cutting.

> Shin SUGIYAMA wrote:
> The G lens that ARIS predicted was announced yesterday. There are also
some new AF lenses that may appeal to MF users also, and a new AF body as
well.

Best regards,
--
Lars Holst Hansen - LHHansen at zi dot ku dot dk
http://www.zi.ku.dk/personal/lhhansen
http://www.egroups.com/subscribe/NikonRepair

From Nikon MF Mailing List:
Date: Sat, 14 Oct 2000
From: Larry Kopitnik kopitnil@marketingcomm.com
Subject: re: 180mm 2.8 ED AF or MF - Which is best?

I have been looking around for a used Nikkor 180mm ED to use on an F3 and have come across both the MF and the later AF version with wide focusing ring. They are both approximately the same price. I know they are both excellent lenses but how do they compare optically, is one superior to the other? As I have the choice of either, which would be the better lens?

Several responses have stated that the manual focus and autofocus versions of the 180 f/2.8 are the same optical design. This is not correct.

The manual focus version is 5 elements in 5 groups. The autofocus version is 8 elements in 6 groups. They are completely different optical designs.

Additional, according to Nikon brochures, the manual focus version focuses down to 1.8 meters, or 6 feet, while the autofocus version focuses to 1.5 meters, or 5 feet. Having the autofocus version, I can verify it in fact focuses to slightly closer than those figures.

When I bought my 180 f/2.8 Af lens, my dealer said he thought the lens was the most optically improved Nikkor in going from manual focus to autofocus versions. That may be hyperbole; I've never shot with the manual focus version so I've not compared their performance firsthand. But I can say I find the manual focus feel of the AF version to be among the better of AF lenses (and I use mine quite a bit on an FM2). And I find its optical performance to be outstanding.

However, I recall a professional photographer telling me that he had worn out two or three of the AF 180s, that while he found it terrific optically, mechanically it was not built to the long-lasting standards of the manual focus version.

Larry

From Contax Mailing List:
Date: Mon, 09 Oct 2000
From: Bob Shell bob@bobshell.com
Subject: Re: [CONTAX] Contax AX: Update of the marketing blurb

That's exactly what Kornelius from Zeiss told me. He said Zeiss was unwilling to make the compromises needed to move only very small lens groups inside a lens for focusing. Zeiss insisted on designing the lens for maximum optical quality and this made the lens components to be moved large and heavy, and lenses using this design just focused too slowly in prototypes with older motors. He pointed out to me that some types of LD optical glass weigh more per unit volume than steel!!! So it required the development of the high-torque ultrasonic motors to make the N1 lenses a reality.

Canon, of course, has had such motors for more than ten years, but their motors are heavily protected by patents and they will not sell or license them to anyone else. Kyocera had to design around the Canon patents, as did Nikon, Sigma, etc.

Bob

> From: muchan muchan@promikra.si
> Organization: ProMikra d.o.o., Ljubljana
> Date: Mon, 09 Oct 2000
> To: contax@photo.cis.to
> Subject: Re: [CONTAX] Contax AX: Update of the marketing blurb
>
> It says, (after the Minolta's introduction to AF camera) Kyocera wanted
> to make AF Contax, but that time motor didn't have enough "torque"
> to move heavy elements of Zeiss lenses with enough speed, so, in order
> to produce AF lens, optical compromis was necessary, and that's what
> Zeiss rejected. But later Kyocera could make smaller motor with big
> torque, enough powerful to move elements without compromis, so Zeiss
> said OK. Thus it comes to G, 645 and N1 lenses.
> (I don't know if G lenses are heavy inside, though...)

[Ed. note: Mr. Brick is a noted photographer, photobook author, and engineer designing autofocus and related optical systems...]
From Leica Mailing List:
Date: Sun, 05 Nov 2000
From: Jim Brick jim@brick.org
Subject: [Leica] Re: Focus thread

Martin Howard wrote:

>Nevertheless, none of the above has anything to do with Jim's assertion that
>autofocus is no good because the programmer who wrote the code for the chip
>doesn't know what you're going to take a picture of.  Again, it has about as
>much relevance as the statement that the guy who paints the shutter speed
>numbers on your Leica doesn't know if it's a sunny day or raining when
>you're taking pictures at your daughter's graduation.
>
>Martin Howard                     |

Actually, it does have much relevance. I just finished both autofocus and autoexposure microcode that will be running in a high-end Agilent/RCA camera. Personally knowing the mathematics involved in making a lens move, gathering data and processing it at a high rate of speed, generating histograms of each "focus" capture and correlating it to the previous capture, and using proportional/integral algorithms to speed-up and slow down the lens as it moves to/away from optimum mathematical convergence, I can tell you that the whole process is prone to subject failure. AF can only look at contrast differences. The algorithms implemented will be different for each programmer. Like color balance. In digital cameras we have Asian and non-Asian color balances. We also have Asian and non-Asian focus/exposure algorithms.

So, it does indeed make a lot of difference who is implementing the exposure/focus/color balance and it is true that these algorithms are purely mathematical. Which is why you can get AF to hunt endlessly if pointed at the wrong subject.

High end cameras such as the D1, F5, EOS1, etc, have many years of experience behind them and do a reasonably good job. you can still make them hunt and still get their exposure algorithms to fail. But it still boils down to that you are the photographer and the camera has no clue what your photographic vision is. It is subject blind and relies on contrast differentials to focus. Exposure gives weights to various matrix configurations (adjustable from nine to 36 in our camera) but still boils the total accumulation of these weighted sectors, to yes... roughly 18% gray.

These systems are simply dumb. Photographers give them too much intelligence. Even those using fuzzy logic and AI use math to interpret contrast ratios and gray densities. Humans are much smarter than this. This is why the same lens touts a higher lp/mm resolution if hand focused vs if auto focused.

Jim

From Leica Mailing List:
Date: Sun, 05 Nov 2000
From: Jim Brick jim@brick.org
Subject: [Leica] Re: Re: Focus thread

Human vision and tonal difference detection is far more acute than what can be "visualized" by a math algorithm reading electronic bits either from a focus sensor array or a piece of the actual photo array in the case of a digital camera.

Humans can focus accurately on items that will cause AF to hunt endlessly. Recently I took the new Contax MF AF camera and pointed it at a Plexiglas magazine (View Camera magazine) rack on the camera store counter, at an oblique angle. It was super easy to focus manually on any part of the rack, anywhere along the entire length because my brain could see what it was and could see when there was a sharp definition at any point along the Plexiglass rack. When switched to AF, the lens hunted in and out forever, never stopping as it could not find sufficient data to generate histogram spike differentials as the lens moved from one plane to another.

On a target that has sufficient contrast lines to enable AF to quickly converge, it still cannot converge to the Nth degree that the human eye/brain can. The human focus mechanism can detect minute differences and adjust the focus accordingly. The same movement in a convergence algorithm will show no difference therefore, AF cannot focus as accurately as a human and therefore gets lower lp/mm marks.

The Asian algorithms (AF cameras - perhaps only digital - intended for the Asian market only) are exposure/focus related and tend to use wider apertures for more background blur than non-Asian algorithms. Non-Asian algorithms tend to want everything in focus and a cooler color balance. Non-Asian algorithms will sacrifice shutter speed for a smaller f/stop and have a warmer color balance. Vice versa for Asian algorithms.

Hey... I just work here. I don't make this stuff up!!! But I have to deal with it daily.

And don't get me wrong... I think AF is great for the type of photography that can use it effectively. And, of course, for those with failing eyesight. As of now, I just happen to have no use for it.

Jim

...

[Ed. note: the Contax AX uses a movable body within a body shell to autofocus, so it can even work with T-mount lenses like the Spiratone 100mm and provide autofocus benefits in the body, not the lenses...]
From Contax Mailing List:
Date: Thu, 09 Nov 2000
From: Bob Shell bob@bobshell.com
Subject: Re: [CONTAX] Makro lens : Confusing

Sure, this can be done. But you won't have diaphragm or meter linkage, which would be prohibitively expensive to modify.

I've used a lot of different lenses with the AX via adapters. I was very surprised to find that it can even autofocus my Spiratone 100mm f/4 soft focus lens!!

Bob

[Ed. note: An important warning...]
from Tests of Classic Pentax Lenses by Peter S. Spiro note:

One of the great things about the Pentax system is that every bayonet mount lens ever made by Pentax (going back to 1975) can still be used with a high degree of functionality on the most modern Pentax SLR...

(One important point that should be noted: some non-Pentax brand K-mount lenses have protrusions that will cause them to get stuck when put on an autofocus camera. Ricoh program lenses are especially dangerous. No non-Pentax lens should be put on a Pentax autofocus camera until it has been carefully examined.)

Date: Tue, 02 Jan 2001
From: Jeff Wiseman elox@hot.rr.com
To: rmonagha@post.cis.smu.edu
Subject: easy fix for this

[Ed. note: An important warning...]
from Tests of Classic Pentax Lenses by Peter S. Spiro note:

One of the great things about the Pentax system is that every bayonet mount lens ever made by Pentax (going back to 1975) can still be used with a high degree of functionality on the most modern Pentax SLR...

(One important point that should be noted: some non-Pentax brand K-mount lenses have protrusions that will cause them to get stuck when put on an autofocus camera. Ricoh program lenses are especially dangerous. No non-Pentax lens should be put on a Pentax autofocus camera until it has been carefully examined.)

Of course, the easy fix for this problem with the P/KAR or P/RP lenses is to simply remove the extra pin that catches on the AF drive. I have done this on several lenses. Quick and easily done.

[Ed.note another example of trying to work around built-in mfger efforts to disable camera use with older lenses and lens adapters, bellows, preset lenses etc.]
From Minolta Mailing List;
Date: Thu, 4 Jan 2001
From: "Sergey Frolov" sfrolov@cqg.com
Subject: Re: how to disable lens mount check on 404 si ?

No. I have tried all listed in FAQ combination - no result. I think, the problem is that 404si is relatively new camera and we don't know to do this or Minolta does not allow us to disable lense mount check. Another problem that Minolta is not widely distributed in Russia, so I cann't consult with expert.

----- Original Message -----
From: Marko B.
To: minolta@egroups.com
Sent: Thursday, January 04, 2001
Subject: Re: [minolta] how to disable lens mount check on 404 si ?

Doesn't anything from this work???

300si Press and hold FLASH and DRIVE/SELFTIMER buttons and move power switch from LOCK to ON. (Off appears in LCD panel)

400si Press and hold Drive Mode and AV buttons and move power switch from LOCK to ON.

500si Press and hold Drive Mode and SPOT buttons and move power switch from LOCK to ON.

505si Super Press and hold Self Timer and SPOT buttons and move power switch from LOCK to ON.

600si Press and hold the LENS RELEASE button and FILM SPEED button with the lens removed and move the power switch from LOCK to ON. (OFF appears in LCD panel)

700si Press and hold SPOT and CARD buttons and move power switch from LOCK to ON.

800si Press and hold SUBJECT PROGRAM and AEL buttons and move power switch from LOCK to ON.(OFF appears in LCD panel).

----- Original Message -----
From: Sergey Frolov
To: minolta@egroups.com
Sent: 4. januar 2001
Subject: [minolta] how to disable lens mount check on 404 si ?

I want to use my old M42-mount lenses on Minolta 404si but I have not found in Minolta FAQ how to disable lens mount check for this camera. May be because Minolta 404si is European mark.

What is analog of 404si on the american market ?
Does anybody know how to do this magic trick with Minolta 404si ?

Thank you in advance,
Sergey Frolov.

and a followup suggestion:
Date: Thu, 04 Jan 2001
From: Peter Blaise Monahon peterblaise@yahoo.com
Subject: Re: how to disable lens mount check on 404 si ?

....

Hi, Sergey Frolov,

For the Minolta Dynax 404si to NOT check for an Auto Focus lens before releasing the shutter, try, while turning the main switch on, holding the [P] and [Self Timer] switches with Function Dial at [ME] position.

--
Peter Blaise Monahon

Date: Wed, 10 Jan 2001
From: jbh@magicnet.net (John Hicks)
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: Contax in low light: Good or not good?

"Ron" rgans@nospamNyc.rr.com wrote:

>Do most MF systems use a passive autofocus? No infrared?

Both Contax and Mamiya are passive, but the Mamiya has a built-in illuminator. I think it's IR rather than the very annoying bright headlight used in some 35mm cameras.

An illuminator projects a pattern onto the subject so the AF module has some contrasty edges to see. It makes no difference to the AF whether it's visible light or IR.

I believe the Fuji 645 point'n'shoot cameras use active IR rangefinding like 35mm p&s; cameras.

As someone else pointed out, most MF cameras don't have AF.

I've played with the Contax just a little; what struck me is that the viewfinder is rather small and dark compared to an Acute-Matte screen in a Hasselblad or a Hi-D screen in a Rollei. Because of that, it may actually be extremely difficult to focus in low light; I don't know if an Acute-Matte equivalent is available for the Contax.

I use an RF camera (Graflex XL) with an f2.8 Planar for MF available-darkness work; if the light is bright enough to see the subject it's possible to focus on it with the RF, and since there's no mirror flapping around and the camera's heavy I can handhold a couple speeds slower than a reflex camera.

---
John Hicks

Date: Tue, 09 Jan 2001
From: w6uv@hotmail.com (Jerry Gardner)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Manual versus Auto-Focus

David Armour said:

>I am looking for some feedback.  I have an older Canon F1 with a single
>lens.  I have returned to photography after a long period.  The question I
>pose is should I stick with this camera and add some used manual focus
>lenses or should I buy into an auto-focus system?

David,

In my own testing, I have found that I can focus manually as well or better than AF every time. I did thorough testing with the Canon EOS-1, EOS-1n, EOS-1V, and Nikon F5. I could do better than all of these.

However, all of my photography is of static subjects. I have the luxury of standing there and tweaking the focus all I want. If you photograph moving subjects frequently, then you might find AF to be helpful.

I also appreciate the feel of older cameras such as the Nikon F3 and Canon F1, along with their lenses. To me, there's nothing like the feel of an old 70's tank of a camera with a butter smooth manual focusing lens. Autofocus gear has always felt insubstantial and plasticy to me, especially the lenses.

--
Jerry Gardner

Date: Wed, 10 Jan 2001
From: frostycat@my-deja.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Manual versus Auto-Focus

Actually, the fellow has a point. Last April I was shooting at NCAA Gymnastics Championships close-in down on the competition floor. My chosen position for horizontal bar was about 45 degrees angled away from parallel with the bar itself. The performer swinging on the bar, therefore, was constantly moving closer and further from me requiring constant re-focusing with my AF 105mm Nikkor lens on F5 body.

Notwithstanding Nikon's claims of how the camera can follow focus quickly, I soon learned that it wasn't fast enough or dependable enough and my own manual focus-by-anticipation was superior. To be fair I wasn't focusing-by-eye. I was manually moving the focus ring to one of four positions I had predetermined would be right depending upon the performers position as I anticipated it.

However, the effect was the same and the comparison is still valid -- my manual focusing was MUCH faster than the camera was capable of in that situation. On most other events, I turned the auto-focus back on again. I'll bet there are other situations where manual focus can be demonstrated to be superior also. Don't get me wrong. I use auto-focus MUCH more than manual and would never give it up. But it does have its limits.

....

Date: Sat, 13 Jan 2001
From: "Malcolm Stewart" malcolm_stewart@megalith.freeserve.co.uk
Newsgroups: rec.photo.equipment.35mm,rec.photo.equipment.misc,rec.photo.technique.nature
Subject: Re: Sigma lens

photos33 photos33@tpg.com.au wrote

> Am thinking of buying a Sigma 17-35 f2.8-4 HSM in Canon mount.
> Anyone got any experience with this lens or any advice.
> GARY

I bought this lens last July and once I'd got over the shock of the price for the 82mm slimline skylight filter, I found it gave excellent results. It's seems fully compatible with my both my EOS10 and EOS3. However despite HSM, it does not permit full time manual focusing. The extra width at "17" is significantly wider than at the marked "20", and I've found this feature useful when taking narrow streets and buildings. I used Provia 100F and on a light box, using a good quality high power loupe, I can't see any loss in sharpness compared with my Canon EF35 f2 - this is from hand held shots taken in the f5.6 to f8 region*. Occasionally I got the sun in shot and yes, you can see ghost images, otherwise flare seems well controlled. I've recently noticed some slight loss of EX paint finish when I allowed the lens to rub against another.

* Haven't tried formal lens testing as I'm satisfied with its performance.

M Stewart Milton Keynes, UK

From: Philip Stripling phil_stripling@cieux.zzn.com
Date: 13 Jan 2001
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Benefits of manual focus

Tony Spadaro tonytony_tony@my-deja.com writes:

>   THe difference is quite simple:
>    You can use the auto-camera in full manual mode, but you can't use
> the manual camera in auto-mode.

True, but ...

I have access to an N50, and I have yet to find a quick way to set the shutter speed in manual mode. As far as I can tell, I have to set it by stepping through speeds shone on the LCD display. I'd be very happy to find out I'm wrong. It takes me much longer to set the shutter speed this way, especially as I have to dig out my reading glasses to see what I'm doing.

If there's not an easier way, then when buying an auto camera that one plans on using in manual, one should use it in manual before purchase.

--
Philip Stripling

From Contax Mailing List;
Date: Thu, 04 Jan 2001
From: Bob Shell bob@bobshell.com
Subject: Re: [CONTAX] N1

> From: "Kaisern Chen" kconeverest@hotmail.com
> Date: Thu, 4 Jan 2001
> Subject: Re: [CONTAX] N1
>
> After many
> years of AF development, however, it seemed electronical AF has its edge
> over the mechanical one but I always wondered why AF medium format Mamiya
> and Pentax still use the mechanical AF system rather than electronical AF
> used by Contax 645.  Nikon has proved to be able to bridge the electronical
> and mechanical AF system in one mount and if Pentax and Mamiya wants to use
> the existing lenses they can still do something like Nikon and have all
> motor drive AF lenses made as another lens line.  Anyone knows why?

Yes, it is a simple matter of access to motors. Canon invented the ring-type ultrasonic motor, the only practical one for moving large masses in big lenses. Later they invented a simplified ultrasonic motor which is now used in their other lenses. Canon refused to sell their motors to anyone else. That's why it took Nikon and Sigma so long to come out with lenses powered by this type of motor. Each had to do their own R & D and make their own versions of ultrasonic motors. In the case of Contax, Kyocera has done their own R & D and made their own motors. But Nikon and Kyocera only have the large diameter ring usm, not the smaller one, which is why Nikon is only using in some larger lenses and why the first generation lenses for the Contax N1 are of such large diameter. Sigma has managed to develop smaller motors, and it is probably only a matter of time before Nikon and Contax have them as well. In medium format, Pentax and Mamiya have not developed ultrasonic motors and so had to design their cameras with traditional coreless electric motors in the bodies. Contax, by simultaneously developing the motors for 35mm and medium format is one step ahead.

Bob

Date: Tue, 16 Jan 2001
From: w6uv@hotmail.com (Jerry Gardner)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Diffuser vs Softener Filter

jj, curmudgeon and tiring philalethist said:

>I'm not talking P&S here, btw, I'm talking real cameras, what kind
>of camera are you using that has inaccurate autofocus when you use it
>correctly?

Canon EOS-1, EOS-1n, and EOS-1V. All had very slight, but measurable autofocus inaccuracies. In the case of the EOS-1n, I tried three samples. They all had inaccuracies to one degree or another.

--
Jerry Gardner
email: w6uv@hotmail.com

[Ed. note: AF eats batteries, see Cold Weather Tips...]
Date: 14 Jan 2001
From: ianr@tarcus.org.uk (Ian Rawlings)
Newsgroups: rec.photo.equipment.misc,uk.rec.photo.misc
Subject: Re: Cold weather and modern autofocus cameras

"Hmmmm" morrowdg@hotmail.com writes:

> I use a Nikon F50 autofocus and am going snowboarding for the next
> few weekends. Does anyone know at what temperature modern autofocus
> cameras stop responding?

When we had snow in Britain recently my EOS3 burned a set of four AA (alkaline) cells in just three films, basically it's the batteries that are more likely to cause you problems than the camera. A regular EOS user I know was swapping lithium cells every three SHOTS once (warming one up in his pocket to recover it then putting it back in) it was so cold, but the camera itself was still working.

> I'm considering buying an olympus OM10 manual camera in case the
> Nikon may prove unreliable!

Using print film (for latitude) and metering occasionally from a seperate light meter kept in a warm inside pocket should do the trick...

Date: Tue, 16 Jan 2001
From: David Chien chiendh@uci.edu
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Benefits of manual focus

while it is true that you can put an AF camera into MF mode and get about the same thing as a MF camera, there are a few differences...

1) MF camera forces the beginning photographer to learn all of the controls and develop a finer grasp of aperature & shutter speed than a AF camera, where you can simply fall back on fully auto mode. Plus, most of the AF lenses on most camera makes don't have good aperature marks, or good MF focusing feel, making users feel less likely to use MF mode, if ever.

2) Better focusing screen for MF. AF cameras usually need their screens swapped out for a microlens/splitimage mirror for the finest control over focusing. Otherwise, it's a real tough thing trying to get accurate focus using most of the modern, clean-as-a-slate mirrors.

3) Cheaper used MF lenses. You can usually get on Ebay truck-loads of MF lenses of excellent quality at 50% or less vs. the same AF lens new.

4) Using a MF camera, you ALWAYS are aware of the affects of focus point. On a AF camera, you tend to look only at what you've got your camera aimed at (and that's always in focus), but rarely at the background and surrounding scene. You forget to sweep the entire scene on a AF camera as a result.

Also, you learn about DOF, hyperfocal and so forth when you don't have anything automatically setting A/S, and you're required to 'think' a bit.

5) Often, MF cameras don't need batteries to operate at all - only for the metering, but even that becomes unimportant as you learn to set the proper A/S by heart.

6) You get really good a winding that camera every time you take a shot (because you'll miss quite a few because you forgot!).

7) You love the heavy heft of the MF equipment, esp. after those reporter dogs are after you! and you need something to throw at them! ;)

--

On the other hand, once you know what you're doing, AF camera gives you everything and more, esp. the excellent Nikon SB flash system, automatically.

--

Realistically, there's nothing special about the MF camera or lenses. Most of them have been superseeded by lighter, similar or better performing modern equipment, but for those that only use MF cameras, some are just better than others. I'd just spend the money on newer AF equipment, pickup a few books like "Perfect Exposure" by Hicks, and try not to depend on the AF too much before knowing what you're doing.

d =)

...er. Leica M series rangefinders and so forth are the exceptions for exceptional MF cameras that'll whip most MF SLRs....

From Contax Mailing List;
Date: Sun, 21 Jan 2001
From: "Blake Ziegler" blakezi@home.com
Subject: RE: [CONTAX] Contax RTS III focusing screens

Hi, Denton,

Manufacturers have a choice of how much "tooth" they put on a focusing screen. They typically take the middle road.

The more "tooth" or fog the screen offers, the better the ability to focus (within limits, of course). As the screen becomes "brighter" focusing becomes more difficult until the point where you are trying to focus on an aerial image. This is very difficult.

Keep in mind that meters must often be re-calibrated when using these "bright" screens (as in the case of the FX-1 Screen for the N1-however, we made a custom function for that one).

Blake
CONTAX, USA

From: ejkowalski@aol.com (Ejkowalski)
Newsgroups: rec.photo.equipment.35mm
Date: 25 Jan 2001
Subject: Re: Technical AF question

It's like using two eyes for 3-D vision. You need distance between two eyes (or sensors) to triangulate and calculate the difference in view between two points. A lens that is too slow has two narrow an opening (too small an aperture) to get two readings from points far enough away from each other side-to-side. And it's the max aperture of the lens that matters, since AF is done at full aperture with the lens wide open, not at taking aperture. It's the same reason why with manual split-circle focusing one half of the circle blacks out if the lens is too slow relative to its focal length, often experienced with telephotos.

EJKowalski

Date: Thu, 25 Jan 2001
From: w6uv@hotmail.com (Jerry Gardner)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Technical AF question

>Can anybody explain the technical reason why most SLRs cannot AF
>without lenses faster than f5.6?  You often hear that's it's because
>there's not enough light with the slower lensest but an SLR with an f8
>lens outdoors gets much more light than an SLR indoors with a f3.5 lens
>yet the one indoors will AF just fine while the one outdoors cannot.
>What am I missing?

Modern SLR autofocus systems use phase detection for focusing. This works much like split-image circles in older manual focus SLRs worked.

Light coming into the lens of the camera passes through the semi-silvered main mirror where it is reflected by a small secondary mirror into the AF module. The AF module has a prism that splits the light into two beams. Each beam is then focused onto a CCD line sensor. By comparing where the two beams fall on their sensors, the camera can determine how far and which direction to move the lens to achieve focus.

The lens aperture restriction arises because, depending on the design of the prism that splits the light into two beams, mechanical vignetting will block the light from one of the beams at small apertures. This same problem occurs with split-image focusing screens in manual focus cameras--when the lens aperture is too small, one of the split image semicircles will go black.

There is a tradeoff involved when designing the prisms that split the light into two beams in an AF system. The larger the "baseline" of the prisms, the more accurate the AF can be, but this also requires a larger maximum aperture. For example, the center cross sensor on the Canon EOS-1n is more accurate than the other four sensors, but this is only the case if the lens' maximum aperture is 2.8 or larger. The other sensors can work, although with less accuracy, down to f/5.6.

-- Jerry Gardner

From Nikon Mailing List;
Date: Mon, 5 Feb 2001
From: Tenrec@aol.com
Subject: Re: [NIKON] AF lens on manual body

melig@x-treme.gr writes:

> Trying to find a 70-300 zoom for my FM2,
> I soon realized that there are not many options in MF lenses (nikkor or
> third party). So I thougt to get an AF lens, suchs as Nikkor 70-300 ED
> or Sigma 70-300 DL Macro and use it at MF mode. But on  this type of
> lenses the focus ring is located a bit far from the body and it has a
> short turning movement. Will I be able to focus acurately and generally

The AF lenses, while perfectly functional on the FM2, are primarily designed to work on the AF cameras, and so the focusing rings are not in the optimum locations for manual focusing. Their "feel" is not as good as the MF lenses, either, and their short focusing throw may make accurate manual focusing a little bit more difficult. (Think of it this way -- back when all Nikon cameras were manual focus, would any lenses have been designed like this? No.)

One other issue that you didn't mention, but I find important with a zoom such as the one you mention: When a zoom lens does not have a constant aperture, the aperture changes as you zoom the lens. This means that your exposure settings will have to be different when the lens is set for, say, 70mm compared to the settings required at 300mm. With the autoexposure cameras these lenses are primarily designed for, this is not much of a problem, but when used on the FM2, you must remeter and reset your exposure EVERY TIME YOU CHANGE THE LENS'S FOCAL LENGTH. This does not make for the fastest handling. That's why I use exclusively constant aperture zooms with my FM2.

Steve

From Nikon Mailing List:
Date: Fri, 16 Feb 2001
From: "L Shepherd" Shepherdlen@btinternet.com
Subject: Re: [NIKON] Autofocus Delay

- ----- Original Message -----
From: "Cathal Gantly" cathal@gantly.demon.co.uk
To: nikon@photo.cis.to
Sent: Friday, February 16, 2001
Subject: RE: [NIKON] Autofocus Delay

> >-----Original Message-----
> > From: Tenrec@aol.com
> > Sent: 16 February 2001 
> > Subject: [NIKON] Autofocus Delay
> >
> > Obviously, this was not a scientific test, but it left me with a general
> > impression.  And, equally obviously, autofocus lag is as important as
> > autofocus speed.
> Amateur Photographer (UK) recently tested the Eos 1 against the F5, and even
> though the Eos had a very slight advantage in focusing speed, the F5 produce
> more useable shots in the sequence. So, more important than speed, is "do
> you get it right?"
>
> Cathal

Let's try and get some perspective. All modern AF systems are pretty fast compared to manual especialy with the fastest bodies and lenses.. Minolta claim outright there AF SYSTEM for the Dynax 7 & is faster than the EOS1v and Canon have not gone to court over the claim. Canon claim to have the fastest AF with the EOS1v but qualify the claim by saying it's with a single point sensor only with latest IS lenses f2.8 or faster. Therefore it might be no coincidence that Nikon have announced an even faster Nikon 300 f2.8.

Britain's British Journal of Photography 23rd August 2000 got Canon to admit

- - Canon is slower than other systems when Canon full area focusing is used

- - rapid focus requires fast lenses (and on Canon this means f2.8 or faster).

- - low contrast (some footballers shirts) makes AF difficult

- - things like football where movement is unpredictable are difficult for AF whereas things like motor sport where movement is predictable are easier.

- - At the time focus tracking was fairly limited - to about 50 km (35 miles) per hour in "ideal" conditions which includes movement in the right direction on both Canon & Nikon systems (Canon statement) which implies Canon mean there is no difference between the 2 systems..

This remarkable frankness came about because Canon sent BJP a 28/70 f3.5-5.6 and a 75/300 f4-5.6 to review, BJP tried them at a football match, and found the AF combination with an EOS1v was not up to the job.

As Cath says, it's the results that count and we do not always have the fastest lenses or restrict the F5 or F100 to central point focus only. Chasing AF speed per se only benefits camera retailers. Most experts at macro work use AF cameras these days but take over 90% of macro shots on manual focus because that combination for that job gives best results. As an ex racing cyclist turned photographer I can also confirm the best sports photographers get the best pictures because they know what will happen where before it happens. Love of the particular sport is more important than camera or lens.

Len Shepherd.

From: pauls@shell3.shore.net (Paul Secinaro)
Newsgroups: rec.photo.equipment.35mm
Date: 6 Dec 2000
Subject: Re: Why can't Nikons newer AF bodies meter w/ MF lenses?

richcochran@my-deja.com wrote:

>The only reason I can think of is that the marketing folks at Nikon
>figured the money they'd make by selling more new AF lenses more than
>offset the money they'd lose by selling fewer of these crippled
>bodies.  Needless to say, they won't be selling one of the crippled
>bodies to me.

Another cynical analysis might be that Nikon knows that the only people likely to be messing with old MF lenses are pros and advanced amateurs. They also know that they can probably nudge these people into a higher end, higher margin body like the F100 or F5 pretty easily, so they take out a few features on the low end in order to dangle a few carrots on the high end. This assumes that the top bodies have higher profit margins, and I really don't know if this is the case. The other manufacturers do this too by the way (e.g. no spot meter on the Canon EOS 30/Elan 7).

Paul

[Ed. note: Thanks to Kent Gittings for sharing these notes on lens aperture display issues - esp. an issue with flash users...]
From Minolta Mailing List:
Date: Mon, 12 Mar 2001
From: "Kent Gittings" kent@ism.com
Subject: RE: Sharp lens for low-bucks?

Be advised that just because the viewfinder says it is 4.5 doesn't mean it really is. This is a fallacy a lot of people don't understand. With auto/shutter priority cameras the viewfinder only shows the reading CLOSEST to actual unless the camera body's computer ROM has values corresponding to 1/3 and 1/2 F-stop values stored in it, which many do not. In fact if you zoom the lens and at some point the value changes from F4.5 immediately to F5.6 then I guarantee that the camera and lens were actually at about F5-5.2. To save ROM space many camera bodies only put in aperture values that correspond to their own lenses, especially at the fixed wide open apertures. But the lens is variable throughout that F4.5-5.6 range and is not only just F4.5 at 70mm and F5.6 at 300. It may be F4.8 at 100 and F5 at 150 and F5.2 at 200. But if the camera body doesn't have those display numbers in its ROM is keep the number of the last one until the actual aperture gets closer to the next display value. Camera doesn't take metering off the numbers, only the real aperture so the shots come out regardless of the fact that the actual aperture maybe F5.

Sigma is one of the few makers who actually covers this issue in their lens manuals. So for instance when you put the 170-500/5-6.3 lens on a number of brands and models of cameras at 170mm it often reads F4.5 instead of F5 because those cameras don't have F5 in their display table so they display F4.5 as being the closest one. And in the same vein the same cameras also can't display F6.3 so they show F6.7 instead. That's why some uninformed people think this lens goes from F4.5-6.7.

In fact if you put the same lens on an Elan it will show F4.5-6.7 but if you put in on an EOS-1 it will show F5-6.3 because the larger ROM of the pro camera includes display data for up to 1/3 F-stop instead of just a fixed table of values.

Kent Gittings.

....

From Nikon MF Mailing List:
Date: Thu, 22 Mar 2001
From: "Bryce Hashizume" bryceh@cpsc.ucalgary.ca
Subject: [MF NIkon] AF vs MF lens durability

Hi folks,

A few days ago Robert Monaghan posted an account of a gentleman who had 3 AF lenses wear out, while his old MF lenses were going strong.

I'm not really surprised by this. I took apart my 60/2.8 AFD to clean it once (apparently slurpees and lenses don't mix) and a couple of the little AF gears were plastic. I can easily imagine them wearing out after some years of hard use, while I imagine that MF lenses are more robustly made (and they don't have any little AF gears). I also noticed that a couple of the little parts that help guide the aperture stop down mechanism were also plastic, so that could be another weak spot.

Even more surprisingly, the plastic parts weren't made of that trademark Nikon plastic that apparently costs $200 per pound, based on the prices of some of their accessories, but cheap white plastic. You know the sort, easy to bend and break, not the greatest quality.

The 60/2.8 is, for an AF lens, fairly well made and it has a decent feel to it. I wonder what kind of parts my 85/1.8, with its notoriously loose AF ring, has in it.

take care,
bryce

From Nikon MF Mailing List;
Date: Thu, 22 Mar 2001
From: yuzhengc@yahoo.com
Subject: Re: [MF NIkon] AF vs MF lens durability

I recently had a bad experience with an AF Nikkor 24mm f2.8D. The lens ceased to perform AF nor transfer any info to the camera. My local Nikon importer in Malaysia wanted to charge me almost USD150 just to get the chip fixed! The lens was otherwise in excellent condition. Furthermore the lens aperture ring markings seem to flake off by itself...AARGH!

Can't imagine it costs so much to repair a supposedly cheaper AF lens that costs only USD280 new in my country. I believe that Nikon was trying to cut my throat in this instance. I just can't believe that a chip would cost almost 50% of the total price. I guess I'd rather stick to purchasing durable used MF Nikkor lenses that would be unbeatable(and at the same time prevent Nikon from extracting my money through bad after sales again and through new purchases). Somehow, sometimes I feel proud of being a Nikon user... but I just envy those Canon users who get way better after sales service and reasonable prices.

I'm very disappointed.

Regards,
Yuzheng

From Rollei Mailing List;
Date: Tue, 10 Apr 2001
From: Bob Shell bob@bobshell.com
Subject: Re: [Rollei] RE: AF Rollei

> From: "Carter, William M., Jr." WCarter@ropesgray.com
> Date: Mon, 9 Apr 2001
> Subject: [Rollei] RE: AF Rollei
>
> Any truth to the rumours that Rollei is considering an AF medium format
> camera?

Not a rumor. Rollei and Hasselblad are both working on this. I don't know about how far along Rollei is, but Hasselblad has had prototype AF systems for around ten years. I'm sure you will see AF from both at some point in the future, perhaps first seeing a camera which works like the Contax RX and has focus confirmation in the viewfinder. This would allow them to offer a camera body which would accept existing lenses.

Bob

From Rollei Mailing List:
Date: Tue, 10 Apr 2001
From: Bob Shell bob@bobshell.com
Subject: Re: [Rollei] RE: AF Rollei

> From: "Kotsinadelis, Peter (Peter)" peterk@avaya.com
> Date: Tue, 10 Apr 2001
> Subject: RE: [Rollei] RE: AF Rollei
>
> Bob,
>
> You mean Hasselblad is actually coming into the 21st Century?
> WOw! Now that is news.  Since they have not done much since 1957
> with their cameras it will be real interesting to see what they do.
> Can you say anything further on it?
>
> Peter K

I don't really know anything else. Some of the people I've known at Hasselblad in Sweden for years have told me that there are prototype autofocus cameras and autofocus Zeiss lenses that have been around for years, in various stages of development. Obviously they have not chosen to bring any of them to production, probably due to cost. Zeiss also built some prototype zoom lenses with shutters for the 500 series cameras. Cornelius Fleischer told me he had borrowed and shot with the prototypes and they were spectacular. They were never produced because of the same thing, they would have just cost far too much.

When Hasselblad and Rollei find themselves losing too much business to the crop of AF medium format cameras then they will be forced to put something into production. The one that stumps me is Bronica. They were the first to announce autofocus in medium format, but have yet to bring anything to market.

And, lest we forget, autofocus was invented by Leica and Honeywell, neither of which ever built a camera using it!!!

Bob

From Rollei Mailing List;
Date: Tue, 10 Apr 2001
From: Bob Shell bob@bobshell.com
Subject: Re: [Rollei] RE: AF Rollei

> From: Hugh Turnbull hugh_turnbull@telus.net
> Date: Tue, 10 Apr 2001
> Subject: Re: [Rollei] RE: AF Rollei
>
> Was Honeywell a real camera company with R&D and all that neat stuff?  I
> thought that they were just an importer bringing the Asahi line into
> North America.

Nope, they had R & D on electronics. Remember the Strobonar flash system? They invented the remote sensor for auto flash, and quite a few other things.

They invented the sensor used in early autofocus systems, and licensed it to camera makers.

Bob

From Rollei Mailing List:
Date: Tue, 10 Apr 2001
From: Edward Meyers aghalide@panix.com
Subject: Re: [Rollei] RE: AF Rollei

I think their camera was called the Visotronic, or something like it. I will look this up tomorrow. They had the basic autofocus patent. They also made excellent flash units and was the importer of Rollei after Pentax left them to go it alone in the U.S. Ed

...

From Contax Mailing List:
Date: Tue, 24 Apr 2001
From: Bob Shell bob@bobshell.com
Subject: Re: [CONTAX] First shots with RTS III...what a joy !

> From: "Austin Franklin" darkroom@ix.netcom.com
> Date: Tue, 24 Apr 2001 
> Subject: RE: [CONTAX] First shots with RTS III...what a joy !
>
>> Canon's IS technology and Nikon's copycat VR technology are, to
>> me, the most
>> important optical breakthroughs in years.  Far more important
>> than autofocus
>> in practical use.
>
> Do you happen to know how the image stabilization works?

Sure. I may have mentioned some time ago my involvement in a project to make a line of image stabilized lenses for 35mm cameras.

Basically, most systems work by inserting a wedge-shaped "lens" into the optical path and then moving it to counteract lens and camera movement. There are three ways to do this. Simplest is to mount the wedge in a gimble and connect it to a weight. The weight is free to move and so resists lens and camera movement and moves the wedge along with it. This "passive" system is what we were working on with Vivitar when a change in ownership killed the project. If this had not happened, Vivitar would have marketed a line of image stabilized lenses and binoculars in the 80s.

The other two ways are both active systems. Simplest is to attach the optical wedge to a bi-directional gyroscope, and this is the approach used in the first commercially available image stabilized lens, the Gyrozoom. This American-made zoom lens was offered for cinematography and high-end videography, but never for still cameras because of its cost and bulk.

Canon took this one step further by using motion sensors connected to tiny gyros and electrical acuators to move the optical wedge. I am pretty sure Nikon's system is similar.

Nikon was actually first on the market with image stabilization in a point and shoot built for them by Goko, but this was a dead end system and unrelated to the new ones.

Bob

From Contax Mailing List:
Date: Tue, 01 May 2001
From: Bob Shell bob@bobshell.com
Subject: Re: [CONTAX] Leica lenses on Contax SLRs possible?

> From: "Kaisern Chen" kconeverest@hotmail.com
> Date: Wed, 2 May 2001
> Subject: Re: [CONTAX] Leica lenses on Contax SLRs possible?
>
> Yes, I forgot to exclude the possibility on mirror lens.  Is there any
> reason why other maker can't do it or they do not see a market there?   CMOS
> on Canon can autofocus f/8 lenses and I did contatly with Nikon F5 with  AF-I
> 600/4 + 2X ( = f/8 ) and the lens autofocus beautifully.

As I understand it the Minolta sensor is the only one wide enough to properly read the donut-shaped exit pupil of mirror lenses.

Bob

[Ed. note: AF isn't really new, now in its 25th year...]
From Rollei Mailing List;
Date: Wed, 11 Apr 2001
From: "Kotsinadelis, Peter (Peter)" peterk@avaya.com
Subject: RE: [Rollei] RE: AF Rollei

No. It was mounted on a lens which was placed on a Pentax body. Although Nikon announced that they were working on an autofocus SLR as early as 1971, and Honeywell had patented AF technology, it was the Konica C35AF which incorporated some of the Honeywell technology that became the first autofocus camera in 1977.

The Honeywell AF device was mounted on a lens which in turn was mounted on a Pentax 35mm SLR body. The lens actually AF'd.

I have a photo of this lens/camera combination in a book I own entitled "The History of the Japanese Camera" published by Eastman house.

Peter K

....

From Rollei Mailing List:
Date: Thu, 12 Apr 2001
From: Bob Shell bob@bobshell.com
Subject: Re: [Rollei] RE: AF Rollei

Canon showed the first working prototype autofocus camera at photokina. Unfortunately I don't have a copy of my book at hand to give the year. It was an interesting TLR system, with the autofocus working through one of the lenses, the photo taken through the other. The system used in this prototype camera never developed into an actual system, though, just as Leica never did anything with Correfot other than collecting royalties on some of its patents.

Bob

> From: John Hicks jbh@magicnet.net
> Date: Wed, 11 Apr 2001
> Subject: Re: [Rollei] RE: AF Rollei
>
> Honeywell developed the Visitronic AF module; the first production  camera
> that used it was the little Konica C35AF, the first AF p&s.
> The Leitz Correfot was, so far as I know, the first AF SLR system, but  it
> was just a concept demonstrator complete with bulky electronics etc tied  to
> an SL-2 body.
>
> John Hicks
>
> jbh@magicnet.net

From: John Halliwell john@photopia.demon.co.uk
Newsgroups: rec.photo.equipment.35mm
Date: Mon, 16 Apr 2001
Subject: Benefits of AF over MF. Value of IS

Tommy Huynh tommyphuynh@yahoo.com writes

>IS is great.  Most people who use it wonder how they ever got along  without
>it.  Depends on what style you shoot though.  If you do alot of
>people/street/PJ work where you don't have time to set up a tripod, it  will
>really make or break your photos.

I don't agree (although I haven't used it much). It takes too long for the IS to stabilise for quick grab shots (most useful in street & PJ work). Personally I prefer using fast enough film/lenses not to have to bother with it. My only IS lens is the 28-135 that is chronically slow and really needs all the help you can get from it!

There are definite advantages with IS, it just doesn't suite all applications (a bit like AF). AF is only useful to me in dark places (where with illuminated AF areas in the finder it is very useful). Otherwise I curse not having manual focus aids in the finder, for normal shots I find myself 'piloting' the AF system to get the desired point in focus and it gets in my way. AF itself focusses on the wrong part of the subject too many times and I've missed enough shots as a result.

--
John

Preston, Lancs, UK.
Photos at http://www.photopia.demon.co.uk

From Leica Mailing List:
Date: Fri, 01 Jun 2001
From: Jim Brick jim_brick@agilent.com
Subject: [Leica] RE: RE: who knows where I want to focus?

Hey FTlix,

Look at some lens resolution charts for Canon and Nikon lenses. They list resolution in two columns. On column for autofocus, one column for manual focus. Manual focus resolution is ALWAYS better than autofocus resolution. Why? Because an autofocus mechanism is incapable of "critical" focus. How do I know this? Because this is part of my work. I just wrote some autofocus algorithms and the electronic signal data that is returned from the AF sensors is incapable of making perceptual differences between being critically sharp and "just" being in focus. You either build a signal histogram in software or you get a digital voltage peak at the point where the camera electronics thinks what you are looking at is in focus. To the AF sensor, it's just numbers, and lots of them. No critical human brain involved. These sensors have a high rate of subject failure. They don't know what it is, specifically you want to focus on as they only see voltages.

AF is OK for some tasks. But totally inept at many. And the problem is that you won't know it until you get the film processed. When you personally are focusing, well, the camera will deliver focus on exactly the part of the subject that you wanted in focus. Why? Because that is where you personally focused.

Jim

....

From Rangefinder Mailing List:
Date: Fri, 8 Jun 2001
From: "Mark E Davison" dmark8@qwest.net
Subject: The superiority of traditional rangefinder focussing over the G2 auto-focus system

Toti Cal= wrote, in reply to Paul Thomas

Paul Thomas wrote:

"One has to go by faith that the intended object is in focus"

And Toti Cal= replied:

"And that's exactly what one has to face with any RF camera, since the lens casts the image directly on the film. With the Gs you have to trust a display and a group of lenses which are moved by a motor, with the others you have to trust a prism and a group of lenses which are moved by a little gnome hidden inside the barrel; in both cases you have to go by faith (and possibly by experience)."

I must say that Toti's experience does not match mine. I have found that the focussing on my G2 fails in many more instances than the rangefinder focussing on a correctly-calibrated rangefinder camera. It is true that you cannot verify correct calibration, but the traditional optical rangefinder focussing is more robust. I agree that in either case you have to go by faith in the calibration, but traditional rangefinder foucssing allows you to use the incredibly sensitive coincidence detection system of your eye and brain to decide what to focus on. It is this flexible, intelligent coincidence detection system that makes traditional RF focussing superior in many situations.

The advantage of the G2 focussing is that, for me, in a situation where I am shooting wide-open, so that zone focussing is not possible, the G2 is faster. It is a great camera for photographing people! It is also possible to focus the G2 one-handed, which is useful when one hand is occupied, such as hiking in rugged terrain or walking with children. Speed and one-handed operation are not small advantages.

However here is a list of situations I have encountered where I find the traditional rangefinder (with human coincidence detection) superior:

Shooting at shiny objects like cars (the G2 will often just not achieve focus),

shooting through dirty or wet windows, or through window screens (the G2 tends to focus on the window or the screen--sometimes you can work around this by putting a finger over the infrared receiving window, to defeat the active infrared focussing),

shooting quickly at thin targets with diagonal orientations: wires, cracks in the pavement. (The G2 will focus, but the camera must first be turned so the horizontal sensor is perpendicular to the wire or crack. Having to turn the camera negates the speed advantage of the G2 focussing.) I often focus on a pavement crack to pre-focus on a point and then wait for the subject to walk or run to that point.

shooting at low contrast targets in dim light (here the G2 seems to depend on its active infrared system alone, and this, in my experience, is not dependable at ranges beyond about 1.5 meters, in the sense that the raw accuracy of the IR system is not good enough to focus a 45 at f2 or a 90 at f2.8. I double checked my G2 against a Nikon 35 Ti, and their IR systems display the same inaccuracies. Also, there is no warning from the G2 that your are only using IR focussing--the only symptom is that you cannot achieve "manual" focussing.)

shooting at skinny objects in front of patterned backgrounds. An example would be a wrought iron gate in front of a garden, where you are trying to focus on the gate and blur the plants. Depending on how much of the horizontal sensor is filled by a bar of the gate, the G2 will focus on the bar or on the background. With a traditional RF system, you can easily choose between the bar and the background. This is a wonderful example of how a traditional rangefinder system allows semantic selection: where there is more than one target in the rangefinder patch, the human eye and brain can decide which one to focus on.

shooting in a room with mirrors (if you try to focus on the edge of the mirror, the G2 can get confused--did you mean to focus on the mirror frame, or the reflection of an object in the mirror). This situation arises frequently in Parisian restaurants, where mirrors are used to make the space look larger, and to cater to the narcissism of the clientele.

In each case the focussing errors of the G2 are NOT problems with calibration. Either the G2 won't achieve focus, or it focusses on the "wrong thing". In some cases there are tricks to make the G2 focus on the "right" thing, in other cases I don't know of one.

Here I must take issue with Mike Johnston's opinion in his 25 best cameras review of the G2 in Photo Techniques. It would NOT be redundant to have a G3 with a traditional rangefinder (with human focus confirmation). Such a camera would offer more robust and selective focussing, at the expense of speed.

Frankly I was hoping to ditch my Leica after acquiring the G2 (the G2 is more convenient, more cost-effective, less surrounded with quasi-religious snobbery, and can be used by less skilled photographers without training) but I have ended up keeping both.

By the way, on the Cosina/Voigtlander vs. G question--it is worth having a Voigtlander just to house the 15mm lens! A great little lens, a cheap body.

Mark Davison

[Ed. note: a benefit to AF cameras - learn to focus better and faster! ;-)]
From: "Jeffery S. Harrison" jshphoto@ktn.net
Newsgroups: rec.photo.equipment.35mm
Date: Fri, 15 Jun 2001
Subject: Re: Leica...more like manual vs. autofocus now

> Modern autofocus cameras are so fast that zone focusing with them
> would seem downright silly.  When the camera can lock onto the subject
> in a fraction of a second, why would anyone bother using an estimate?
> Some autofocus cameras even have a focus-lock feature, so that one
> doesn't have to re-focus before each shot.  And, of course, virtually
> all automatic SLRs can be operated in fully manual mode, it that's
> what seems best in a given situation.

I'm not completely sure why you're taking such an extremist position here. I can't comment on Leica specifically since I don't own one (my only range finder cameras are medium format) but most of my cameras are manual focus.

I also own two auto focus cameras (F5 and F100) and I just don't get the results you describe to the degree that your description implies. Yes under optimal conditions my F5 and my F100 will both focus on my subject much faster than I can typically accomplish manually. On the other hand there are many times where I can focus more reliably and quicker than either of those cameras are capable of.

As others have pointed out the auto focus cameras have difficulty in low contrast situations but they also have trouble in a crowded view finder where your subject is not in front. When shooting soccer games (I shoot kids ages 7-18 playing soccer in the summer/fall here) I've often found that I missed a shot because the camera was not focused on the player I had in mind.

I was normally using my F5 because of how fast the auto focus is plus the motordrive as well as how comfortable the camera is to use. As an experiment I hooked up a motordrive to my F3 and took it to a couple of games. I could use it in aperture priority as easily as the F5, it was less comfortable to shoot with but I had fewer shots missed because of not being focused on the subject I had intended. The 'slowness' of the manual focusing was not the factor I had always assumed it would be.

I also find that at air shows the auto focus is not necessarily all it's cracked up to be. The subjects (especially modern jets) move fast enough that auto focusing is problematic. The other problem with an air show is that in order for the auto focus to reliably follow the subject you have to keep the active sensor on the subject and every time you move it a little off the subject the camera as to re-acquire and lock onto the subject making it harder to maintain accurate focus.

The requirement to keep the active sensor on your subject makes it harder to shoot creatively in a rapidly changing situation like a soccer game as well. Being required to keep that sensor on my subject means that often I can't put the subject where I want and have the camera stay focused (focus lock does not work because the subject is running and the focus distance is continuously changing).

One thing I can say about auto focus that I read and didn't believe until I got a camera that has it is that it has made my ability to focus manually better. When I read that it sounded like a lot of BS until I had used my F5 for about a year. What the author speculated was that his manual focusing had improved because his eye learned what 'in focus' looked like while using an auto focus camera. I must say that after about a year of the F5 I found I could focus much more rapidly and accurately on my manual focus cameras than I ever could before and the only explanation that makes any sense is the one that author presented.

Jeffery S. Harrison

[Ed. note: Do AF zoom lenses need to be two touch zooms? No...]
From Nikon MF Mailing List;
Date: Fri, 22 Jun 2001
From: "C.L.Zeni" clzeni@MINDSPRING.COM
Subject: Re: Re: Best AF lenses for MFing

Charles Thorsten wrote:

> John Munford wrote:
>
> > Not that I'm giving up on Nikon MF lenses, but a recent post made me
> > curious.  I always prefer a push-pull MF zoom lens as opposed to a  2-ring
> > setup. Seems just about every AF zoom I see is a "two-touch".
> >
> > I know of the original AF 70-300 being a one-touch, but are there any  other
> > Nikon AF zooms out there that are also one-touch?
>
> The first two versions of the autofocus 80-200mmf/2.8 ED were
> one-touch zooms (albeit with no tripod collar).  This is the only
> AF lens I know of that's a true one-touch, where the same ring
> controls zoom and focus.  There are several other zooms that are
> push-pull, but have a separate small focusing ring in front, such as
> the 35-70mmf/2.8 and 75-300mmf/4.5-5.6.

And I can attest that the one touch 80-200/2.8 work superbly as MF lenses...easy to use, quick to focus, nice feel.

--
Craig Zeni - REPLY TO --} clzeni at mindspring dot com
http://www.trainweb.org/zeniphotos/zenihome.html
http://www.mindspring.com/~clzeni/index.html

From Leica Mailing List;
Date: Tue, 01 May 2001
From: Jim Brick jim_brick@agilent.com
Subject: [Leica] Re: autofocus macro

Autofocus MACRO is an oxymoron.

The limited DOF when photographing at macro distances require focusing on planes that, for AF, is impossible.

Jim

Date: Sun, 10 Jun 2001
From: John Halliwell john@photopia.demon.co.uk
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Leica...

Herbert Kanner kanner@acmd.org writes

>Come on; what is all this nonsense.  I use the rangefinder except when
>in a situation where I need to make quick "grab" shots, and there is not
>time to focus on the subject.  Then, either I scale focus, or if it is
>practicable, use the rangefinder on an object in some other direction
>than the subject, but which appears to be about the same distance from
>me.  Wouldn't any competent photographer use exactly the same technique
>with an SLR?

Many SLR lenses these days no longer have DoF scales, many others have such poor DoF scales to render them unusable or unreadable (sometimes both). This affects not just zooms, but even many primes (some lenses don't even have focus distances marked on them anymore - cost cutting gone crazy). Many AF lenses have such small travel of the focussing ring (sometimes only a quarter turn from min focus to infinity), the distances are either all scrunched up or half of them are completely missing (so it's much harder just reading the focus distance the lens is set to).

Apologies to those Leica users who've never seen a crap plastic lens without focus or DoF scales and with a sloppy focus ring. You really don't know what you're missing out on!

--
John
Preston, Lancs, UK.
Photos at http://www.photopia.demon.co.uk

Date: 22 Jul 2001
From: ramin@math.toronto.edu (Ramin)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Full Circle: Moving Up To Manual Focus (an essay)

"Joseph Meehan" sligojoe@hotmail.com wrote

> Hey go all the way.  Get a 4x5 view camera.  ;-)
>
>     {Begin Quote}
>      Walking back to our cabin I realized that even though my friend's
> new camera was amazing, no doubt it has far more computing power than my
> first PC, I couldn't have taken the ski-lift pictures using it. Spinning
> a dial or pushing  a button to rotate through focus zones would have
> taken as long or longer than nudging the focus ring on my old Rokkor-X
> lens.
> {End Quote}
>
>     I have been in photography long enough to have used 4x5s for taking
> wedding photographs when 2 1/4 stuff was still considered too amateur.
>
>     I have never been able to take a photographs faster than with my
> current auto focus 35mm and often faster.  On the other hand, there are
> few times it is any faster or better, and I often use it in manual mode,
> especially when I need speed.  I don't spend much time playing with the
> dials, frankly I have never used several of them other than to play with
> once or twice.
>
>     Cameras are tools and if you know how to use them, old or new you
> can get the job done, don't blame the tool for a poor result.

A tool certainly is responsible for poor results some times. But it's not responsible always. And in the cases he mentioned he clearly showed the poor results have something to do with the tool itself!

But the mistake he is doing is that he thinks it is the the AF that is responsible. But in fact nothing is wrong with AF, and his arguments in fact tell that Canon EOS control lay-out is just so poor that you will be slowed down whenever you want to focus on a specific point in the frame which does not cover by one the focus sensors.

I have owned EOS camera for many years and i do know that in most of the cases the subject is not covered by any of the focus sensor meaning that you have to focus/ lock the focus/ recompose/ take the shot. The EOS lay-out just makes this as slow as manuaully fovusing or even slower than that!

One thing that majority of Canon users do is just let the camera decide which point to focus and they don't bother themselves in checking where it has done.

This in fact gives a sharp picture most of the time simply because novices/beginnners often put the subject in the middle of the frame! They don't know any thing about compostion. And they don't see the difference on focusing on the eyes or somewhere on the shirt (in those small prints)!

Based on my raw observations, people who are using modern AF slr's (other than professionals and knowledgeable photographers which in fact make only a small portion of the market) are getting more out of focus blurry images than those who use MF cameras! My parents with an old Lubitel TLR almost never got an out of focus picture, while those who are using lower end slr's very possibly get blurry pictures if the scene in the frame is not flat, or the subject is not covered by any of the focus sensors. The problem is that they simply have not learnt what AF means. To them F means AF, not AF where you want it. They are not aware of why they are getting blurry pictures some times. They often think ther eis a chance here that is beyond the control!

Any way, as I mentioned it's not AF itself that slows down focusing, but the poor control lay-out which is a barrier whenever one wants to focus on a very specific location in the frame.

Ramin

Date: 22 Jul 2001
From: dilbertdroid@aol.com (Dilbertdroid)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Full Circle: Moving Up To Manual Focus (an essay)

I'm not sure how valid some of these complaints about AF cameras and their control layouts are.

Typical amateur photographers put EVERY subject in the middle of the frame-- it's the most common compositional error of all time, and seems almost universal.

All the AF cameras I use allow easy focusing then reframing for composition without loosing focus lock. I use the same technique for point and shoots and incidentally, the same technique with the Leica which requires the subject to be in the central focusing patch to focus, and then recompose.

Main problem with amateurs is that after focusing, they don't know how to reframe the image.

Main problem with AF cameras for me has been AF performance with slow lenses, dimly lit scenes and lack of edges in the focus area.

The problem also surfaces with MF cameras, and I have seen MF cameras that suffer from dim screens too. Rangefinders can help with brighter viewfinders but focusing accuracy still tends to wane as subjects get dim.

From Rangefinder Mailing List;
Date: Wed, 30 May 2001
From: "Merritt, Robert (ING)" MerrittR1@ING-AFS.com
Subject: RE: [RF List] RF lens speed

Jim --

Where you get into trouble with slower autofocus SLR lenses is if you use filters -- a polarizing filter or an orange filter for black and white, attached to a slower AF zoom at longest focal length, may seriously challenge the camera's AF system.

You're right that many lenses are at less than their best wide open. The reputation Leica lenses have is that they are better wide open than other brands at the same aperture. I don't know if that's true or not.

Also, I have read, and have no reason to doubt, that achieving the same level of sharpness at 1.4 as at 2.0 is difficult. Thus, comparing different brands of lenses at different apertures can be enlightening -- the differences at 2.8 or 4.0 may be virtually nonexistent, and continue to be so to f11, but at 1.4 or 2.0 there may be measurable (which is not the same as visible!) differences.

I'm not sure it follows that a lens with a relatively modest maximum aperture, such as 2.8, will be worse wide open than a faster lens stopped down to 2.8. I think the critical measurement is the aperture itself, not whether it's the maximum aperture or not.

...

From Sigma Lenses Mailing List:
Date: Mon, 30 Jul 2001
From: o.ffrench@free.fr
Subject: Re: Wide angle lenses and D30

> I haven't heard much about the DG series of primes, but the 20/1.8
> looks awfully tempting.  I'm wondering (A) how it performs on a D30
> wide open, particularly at the edges, and (B) how it performs on
> film, with the edges being more of a concern.  Plus, even if I get
> this lens, I envision that I'd want to go wider...

I've been using this lens for a few months now, on an EOS30. I really appreciate the fast aperture and 20cm close focusing distance. Those were the main reasons why I purchased it, apart from the fact that it cost less than a 17-35 zoom.

I've not used it wide open much, mainly because I tend to use 400 ISO film, but in some cases the shallow depth of field is a bit deceptive and some pictures I took at F2.8 do not look very sharp.

I've read on a message from the EOS list that there was a compatibility issue between the new F 1.8 lenses and the D30. Here's the message:

Henry Posner/B&H; Photo-Video henryp@bhphotovideo.com wrote:

Japanese company announces repair program for affected Japanese customers...

Sigma Japan has announced problems with four of its fixed focal- length lenses when used with certain Canon EOS cameras (specifically, the D30, EOS-1V, EOS-1N, and EOS-1)... Sigma says the following lenses will have aperture control problems with these cameras:

*   20mm F1.8 EX DG ASPHERICAL RF,
*   24mm F1.8 EX DG ASPHERICAL MACRO,
*   28mm F1.8 EX DG ASPHERICAL MACRO,
*   APO MACRO 180mm F3.5 EX IF HSM.

Could not find this info on the Sigma US website...

From Minolta Mailing List:
Date: Thu, 6 Sep 2001
From: "Ze'ev Kantor" zeevk@netvision.net.il
Subject: RE: Re: AF operation

Hello Alex,

To refresh my memory I browsed through some literature I have and found
a compact but clear explanation of Minolta's AF system in the original
Maxxum 9000 brochure. I have scanned the relevant contents and posted it
in the files section of this group, at:
http://groups.yahoo.com/group/Minolta/files/AF%20Maxxum%209000.JPG
The file is around 300K but higher compression caused the text to be
difficult to read.

In regard to the question(s), the Phase Detection system detects the
distance between two identical images projected onto a CCD. The
electronic brain of the camera has to determine for each of the two
projected images a reference point in order to calculate the distance
between the images. If the original image does not have sufficient 
details (i.e. contrast) it is more difficult for the electronic brain to
determine the reference points. Take into account that the projected
image might be greatly out of focus - thus blurred.

Ze'ev Kantor
zeevk@netvision.net.il


-----Original Message-----
From: Alexander Koz [mailto:alexanderkoz@excite.com]

My first guess is that phase-detection system allows camera to decide
where the focal plane is, behind or in front of subject, and minimize
hunting. Secondly, it uses contrast-edge type CCDs as its main
detectors, i.e. it is improved contrast detecting system. Am I right,
Ze'ev? 

Alex.

-----Original Message-----
From: Alexander Koz [mailto:alexanderkoz@excite.com] If I understand
correctly, most modern SLR use phase-detecting AF systems rather then
contrast-edges calculation, right ? (including our Minoltas, of course)
If so, how would you explain subject edge's contrast sensitivity which
is mandatory for any of our Minolta SLRs (and apparently of all other
major brands) AF operation ? AF system in 700si/800si (those I use) has
troubles to perform stable AF with very little contrast level of the
subject (although it's sensitivity is still rigorous comparative to some
other brands).

That would rather say about using contrast-edge model instead of
phase-detecting, am I wrong ?

Regards, Alex 

Date: Fri, 28 Sep 2001 
To: rmonagha@post.smu.edu, w.j.markerink@a1.nl
From: "Neil K." tela@tela.bc.ca>
Subject: EOS and manual lenses


  Hi. In case you're interested I've written up a page on using manual 
lenses on EOS cameras, with links to your sites.

  http://www.grocible.com/photo/manual-lenses.html

  - Neil K

-- 
--
  t e l a  computer consulting + design   *   Vancouver, BC, Canada
                  phone: (604) 254-0520   *   email: tela@tela.bc.ca
                    web: http://www.tela.bc.ca/tela/


From: Bill Tuthill ca_creekin@yahoo.com>
Newsgroups: rec.photo.equipment.35mm
Subject: AF speed comparison [Was: Canon]
Date: Fri, 26 Oct 2001 

Thanks, Wotan!  I reformatted and sorted your list first by
50mm scores and then by 200mm scores.  Unexpected results:

Wotan wotan@wotan.com> transmitted:
>
> Color Foto magazine (Germany) tests for AF speed.

> Camera                         50mm          80-200 at 200mm
> ------------------------------------------------------------
> Nikon F100                     298                       551
> Canon EOS 3                    347                       506
> Minolta Dynax 9                356                       836
> Nikon F5                       367                       583
> Pentax MZ-3                    380                       711
> Pentax MZ-5N                   385                       724
> Minolta Dynax 7                423                       675
> Pentax MZ-30                   426                       790
> Canon EOS1v                    451                       464
> Sigma SA-9                     480                       826
> Nikon F80                      482                       679
> Sigma SA-7                     486                       906
> Nikon F65                      500                       664
> Canon EOS 300                  511                       612
> Pentax MZ-S                    579                       933
> Canon EOS 30                   597                       600
> Canon EOS 33                   603                       607
> Minolta Dynax 505si super      747                       1066
> Minolta Dynax 404si            783                       1156
> Pentax MZ-7                    785                       1074
> Canon EOS 3000 N               892                       1028


> Camera                         50mm          80-200 at 200mm
> ------------------------------------------------------------
> Canon EOS1v                    451                       464
> Canon EOS 3                    347                       506
> Nikon F100                     298                       551
> Nikon F5                       367                       583
> Canon EOS 30                   597                       600
> Canon EOS 33                   603                       607
> Canon EOS 300                  511                       612
> Nikon F65                      500                       664
> Minolta Dynax 7                423                       675
> Nikon F80                      482                       679
> Pentax MZ-3                    380                       711
> Pentax MZ-5N                   385                       724
> Pentax MZ-30                   426                       790
> Sigma SA-9                     480                       826
> Minolta Dynax 9                356                       836
> Sigma SA-7                     486                       906
> Pentax MZ-S                    579                       933
> Canon EOS 3000 N               892                       1028
> Minolta Dynax 505si super      747                       1066
> Pentax MZ-7                    785                       1074
> Minolta Dynax 404si            783                       1156


From: skip shadowcatcher@home.com>
Newsgroups: rec.photo.equipment.35mm
Subject: Re: AF speed comparison [Was: Canon]
Date: Fri, 26 Oct 2001 

Bill Tuthill wrote:

> Thanks, Wotan!  I reformatted and sorted your list first by
> 50mm scores and then by 200mm scores.  Unexpected results:
>
> Wotan wotan@wotan.com> transmitted:
> >
> > Color Foto magazine (Germany) tests for AF speed.
>
> > Camera                         50mm          80-200 at 200mm
> > ------------------------------------------------------------
> > Nikon F100                     298                       551
> > Canon EOS 3                    347                       506
> > Minolta Dynax 9                356                       836
> > Nikon F5                       367                       583
> > Pentax MZ-3                    380                       711
> > Pentax MZ-5N                   385                       724
> > Minolta Dynax 7                423                       675
> > Pentax MZ-30                   426                       790
> > Canon EOS1v                    451                       464
> > Sigma SA-9                     480                       826
> > Nikon F80                      482                       679
> > Sigma SA-7                     486                       906
> > Nikon F65                      500                       664
> > Canon EOS 300                  511                       612
> > Pentax MZ-S                    579                       933
> > Canon EOS 30                   597                       600
> > Canon EOS 33                   603                       607
> > Minolta Dynax 505si super      747                       1066
> > Minolta Dynax 404si            783                       1156
> > Pentax MZ-7                    785                       1074
> > Canon EOS 3000 N               892                       1028
>
> > Camera                         50mm          80-200 at 200mm
> > ------------------------------------------------------------
> > Canon EOS1v                    451                       464
> > Canon EOS 3                    347                       506
> > Nikon F100                     298                       551
> > Nikon F5                       367                       583
> > Canon EOS 30                   597                       600
> > Canon EOS 33                   603                       607
> > Canon EOS 300                  511                       612
> > Nikon F65                      500                       664
> > Minolta Dynax 7                423                       675
> > Nikon F80                      482                       679
> > Pentax MZ-3                    380                       711
> > Pentax MZ-5N                   385                       724
> > Pentax MZ-30                   426                       790
> > Sigma SA-9                     480                       826
> > Minolta Dynax 9                356                       836
> > Sigma SA-7                     486                       906
> > Pentax MZ-S                    579                       933
> > Canon EOS 3000 N               892                       1028
> > Minolta Dynax 505si super      747                       1066
> > Pentax MZ-7                    785                       1074
> > Minolta Dynax 404si            783                       1156

I assume the measurements are milliseconds?  As I read down the list, I
was thinking, "Just how fast does it have to be before it's just
bragging rights?" After all, how much perceived, rather than measured,
difference is there between the EOS3 at 506 ms and the Nikon F100 at 551
ms, for the 80-200 lens?  Then I scanned farther down the list and saw
cameras pushing for 1000 ms, like the EOS3000 (1028) Pentax MZ-7 (1074)
and Minolta Dynax 404si (1156).  That's over a tenth of a second,  which
could be critical.
Two other things struck me.  First, it would seem, just from these
figures, that the Canon 1v is biased toward focusing longer lenses than
the Nikon F5, and, second, that the second line cameras from Nikon and
Canon, the EOS3 and F100, focus faster than their "pro" counterparts.
Maybe the more rugged internals have enough more inertia to slow things
down?
Skip


--
*********************************************************************
    SHADOWCATCHER IMAGERY

Fine Art Black and White Photography
 http://www.shadowcatcherimagery.com
    Skip and Heather Middleton
*********************************************************************



Date: Mon, 05 Nov 2001 
Subject: Re: [Rollei] Rollei at Photo Expo NYC
From: Bob Shell bob@bobshell.com>
To: rollei@mejac.palo-alto.ca.us>

I think they were so willing to talk about it because they *almost* had one
to show in NYC.  Apparently some subcontractor was a few days late
delivering a key component.  I had urged them to show it, even if
non-working, but they decided otherwise.  I was very surprised that Pentax
was not only not showing their new 645, but that no one at their booth
seemed to even know about it!  It was announced in Japan a couple weeks
ago.  

Bob

> From: "David Freedman" dpfreedman@worldnet.att.net>
> Date: Sun, 4 Nov 2001 
> To: rollei@mejac.palo-alto.ca.us>
> Subject: Re: [Rollei] Rollei at Photo Expo NYC
> 
> While there may have been nothing new at the Rollei table, Berndt seemed
> unusually willing to talk about the upcoming auto-focus camera.  He said the
> official press release would arrive in February with the actual camera to
> arrive some time thereafter.  It will offer focus confirmation with existing
> lenses and full AF with a new line of lenses.  First new AF lens wil be the
> 180/2.8 Schneider. There will also be a new zoom from Schneider. Best of
> all, the new camera will handle flash fill correctly!


Date: Mon, 05 Nov 2001 
Subject: Re: [Rollei] Rollei at Photo Expo NYC
From: Bob Shell bob@bobshell.com>
To: rollei@mejac.palo-alto.ca.us>

Well, they did have the new compact camera!  That was certainly new.

Also, no surprise them teaming up with Horseman since Tosh Komamura, owner
of Horseman, is the Japanese distributor for Rollei.

Bob

> From: ARTHURWG@aol.com
> Date: Sun, 4 Nov 2001 
> To: rollei@mejac.palo-alto.ca.us
> Subject: Re: [Rollei] Rollei at Photo Expo NYC
> 
> The Rollei table was as usual, with nothing much new to show, but Rollei was
> much in evidence at other stands.  The Rollei X-Act bellows camera was in use
> in several digital displays, as was the 6008i in several others. Most
> impressive was the new X-Act-D, a joint effort with Horseman that claims to
> be "the world's first view camera designed exclusively for high-end digital
> photography." This camera uses a built in CPU and the Horseman ISS G2 system
> for full electronic control. It works with no fewer than nine digital backs.


To: PentaxMF@yahoogroups.com
From: roland.vink@aut.ac.nz
Date: Mon, 12 Nov 2001 
Subject: [PentaxMF] Re: Pentax 645N

> Is the autofocus mechanism of the camera in the body, or the 
> lenses? 

The AF mechanism is in the body. The 645N uses the same AF system 
Pentax and Nikon use with there 35mm SLRs. If there is a problem with 
AF, it will probably be with the body, not the lens.
It might be worth comparing your camera with another to see if your 
camera really is slower. And if you don't use AF much anyway, why 
worry about it?

By the way, this is my first posting here - Hello! I just bought a 
Pentax 645, 75/2.8 and 45/2.8 from ebay, still waiting for them to 
arrive, and I already have the 120/4 macro. I'd be interested to 
hear from anyone who has used this gear... This is my first foray 
into MF after using Nikons for years. I'm looking forwards to using 
it.

Roland


From: "J.Smith" pathfinder_1492@yahoo.com>
Newsgroups: rec.photo.equipment.medium-format
Subject: Rollei 6008 Auto Focus Medium Format
Date: Thu, 20 Dec 2001 

Just saw mention of the new Rollei 6008 Auto Focus medium format camera in
January 2002 issue of Shutterbug magazine (on newsstands now).  This will be
the successor to the 6008 Integral.  Will debut with 3 AF lenses:  80mm f/2;
180mm f/2.8; 60-140mm f/4.5 Zoom.  No details on prices or exactly when it
will be avialable.

Has anyone seen any mention of this new camera any where else?  Nothing on
Rollei web page.



Date: Tue, 14 Aug 2001 
From: Akhil Lal akhil.lal@bcc.cuny.edu>
To: hasselblad@kelvin.net
Subject: Re: Non Hasselblad Advice From Contax Users

Hello Joe,

Perhaps I can shed some light on this.

Shortly after the Contax 645 was announced, but before it went on sale,
a non working model was displayed at Ken Hansen's in NYC at one the the
"Contax Days". I asked the Contax reps why they chose to make a 645
insted of a 66 and got a variety of unconvincing answers ranging from:
"it's what wedding photographers told us they want" to "this is the MF
format of the future".

Finally one of the reps introduced me to one of the Contax guys who had
been lurking in the background. I gathered he was high up in the
company. He all but said that because of the tie up between Zeiss and
Hasselbald, Zeiss had declined to participate in an AF 66 project with
Kyocera (and remember that today Contax is a Kyocera/Yashica product.
Hence the 645 format. By the way, he also implied that "another
manufacturer" was working with Zeiss on an AF 66 system - this was about
3 years ago.

Regards,
Akhil

Joe Codispoti wrote:
> 
> Andre Oldani's post reminds me that I have been wondering why Contax decided
> to manufacture a 645 instead of a 6x6.
> No doubt the fact that they supply lenses to Hasselblad has something to do
> with the decision.
> 
> I have been using Haslelblads since 1980 and, when I needed to upgrade
> recently, I would have considered the Contax 645 where it not for the
> rectangular format. I don't like turning a bulky camera sideways to
> acommodate the film format.
> 
> Joe Codispoti
> 


Date: Wed, 15 Aug 2001 
To: hasselblad@kelvin.net>
From: Henry Posner/B&H; Photo-Video henryp@bhphotovideo.com>
Subject: Re: Hasselblad and Contax differences

you wrote:
>I agree with Mark, that the Contax 645 is an excellent camera system.
>the word on the street is that the are not holding up as well for the
>wedding photographers

Our reps at last year's WPI convention said their impression was that the 
Contax was kickin' the Mamiya 645AF's butt. This was en entirely 
UNscientific poll.
--
regards,
Henry Posner
Director of Sales and Training
B&H; Photo-Video, and Pro-Audio Inc.
http://www.bhphotovideo.com


From: Gordon.Cole@sce.com
Subject: Re: Non Contax Advice From Hasselblad Users
To: hasselblad@kelvin.net
Date: Wed, 15 Aug 2001 

Jim Brick wrote:
Don't get me wrong. I think Contax makes dynamite cameras. But the Contax>

645 simply cannot compete with the established King of MF. The
Hasselblad.>

I'm not sure how much the Contax was meant to compete with the Hassie.
There seems to be a pretty well-established niche, composed of the Mamiya
645, Pentax 646, and now the Contax 645, which satisfies a need for those
who need the AF, AE, and other fast-action features of the 35mm camera, but
with a negative that's 3x the size.  It would seem to me that the Contax's
competition is Mamiya and Pentax, not Hasselblad.  Blads are comparatively
slow, mechanical, difficult to learn to use properly, and expensive.  The
Hassie's only real competition is Rollie, with its electronic features and
Zeiss lenses.  I can only speak for myself in saying that I chose
Hasselblad over all other MF cameras because there was simply no other
camera made that met all of my requirements for quality, reliability,
hand-holdability, full manual operation capabilities, and the largest
negative size that would meet those requirements.  If I'd wanted to use an
AF/AE machine, I'd stick to my Nikon.  Obviously, there are many who demand
this type of MF camera for their specific type of requirements.  I've seen
more and more Mamiya 645's, Pentax 645's, and Contax 645's showing up in
national wedding photo competitions (though there are still more Blads
there than any other type, that may be simply because some people can't
afford to switch systems that easily).    Hasselblad has a pretty firm
grasp on its niche, as witnessed by Rollie's failure to match their sales,
despite having more electronics than all but the top-end Hasselblads.  That
large numbers of photographers continue to purchase an expensive,
all-mechanical camera that has remained largely unchanged since the 1950's
testifies to how well Hasselblad fills that niche.


[Ed.note: Is APS already on the way out, thanks to digital killing it off?]
From leica mailing list:
Date: Wed, 06 Feb 2002 
From: Jim Brick jim@brick.org
Subject: [Leica] APS out ?

BJP Quote

"One of the world's leading camera manufacturers is switching its
research and development team away from the Advance Photo System format
in favour of digital.

The decision by Minolta to stop developing new APS camera models
provides the first sign that the 24mm format, introduced just over five
years ago, may be entering its first death throws."

Jim 

From minolta mailing list:
Date: Wed, 16 Jan 2002 
From: "giuseppe stama" giuseppe.stama@tiscalinet.it>
Subject: Re: Reversing  a lens

Hi, Manfred

Look at this link in the MUG page

6.2.1 How to disable the lens mount check

http://www.sds.com/mug/af-tips.html

Here You can find what you want.

And ... Manfred, I have bought the HAMA 9544/5 reverser adapter for 55mm
filter thread, thank you again for your useful information. Is very simple
to use, and the f-stop ring is very precise. And I am very happy that is
on offer, only 7.5 EUR.


Ciao Giuseppe


----- Original Message -----
From: "Maisch, Manfred" manfred.maisch@epcos.com>
To: Minolta@yahoogroups.com>
Sent: Wednesday, January 16, 2002 10:53 AM
Subject: [Minolta] Reversing a lens


> Hi,
> does anyone know, how to unlock the shutter of a 600si with a reversed lens?
> I know this for my 9xi, but I lost the manual for the 600si.
> Thank you
> Manfred


From minolta camera mailing list:
Date: Wed, 16 Jan 2002 
From: "giuseppe stama" giuseppe.stama@tiscalinet.it>
Subject: Re: Reversing  a lens, description

Excuse me, maybe is better if I post the solution then point you at the
link. But is also right to point someone to that useful web page.

"Press and hold the LENS RELEASE button and FILM SPEED button with the lens
removed and move the power switch from LOCK to ON. (OFF appears in LCD panel)"

Ciao
Giuseppe


[Ed. note: here is another example of the sort of tricks you may have to play
to convince your camera to work with T-mount lenses, microscopes, telescopes..]
From minolta mailing list:
Date: Wed, 12 Sep 2001 
From: "Steven Van Dyke" s_van_dyke@att.net
Subject: Re: T-mount on a Minlta 505si Super

Pulled from a file I pulled down from the CompuServe Photography forum
(which you can get to via www.phototalk.com):
-----------------
USING MAXXUM CAMERAS WITH T-MOUNT TELESCOPES,
SPOTTING SCOPES, MICROSCOPES, AND NON-MAXXUM LENSES




Camera   Procedure

5000, 7000   No preparation needed to use
9000, 3000i,   T-mount lenses.
5000i, 7000i,
8000i

2xi, 3xi  Use of T-mount lenses, microscopes,
Spxi   and telescopes is not possible.


5xi   Press and hold SPOT and FUNC.
   buttons and switch from LOCK to ON.

7xi/9xi   Press and hold AEL and FUNC.
   buttons and move power switch from
   LOCK to ON.

300si   Press and hold FLASH and DRIVE/SELFTIMER
    buttons and move power switch from
    LOCK to ON. (Off appears in LCD panel)

400si
 Press and hold Drive Mode and AV buttons
   and move power switch from LOCK to ON.

600si   Press and hold the LENS RELEASE button and
   FILM SPEED button and move the power
   switch from LOCK to ON. (OFF appears in
   LCD panel)

700si   Press and hold SPOT and CARD buttons and
   move power switch from LOCK to ON.

------------

The 505 isn't listed, but I think it's the same as 400.  In any case, 
you've got some things to try.

Enjoy!

Steve :->


From Minolta mailing list
Date: Tue, 4 Sep 2001
From: "Ze'ev Kantor" zeevk@netvision.net.il
Subject: RE: AF operation

Hi, Alex.

Recently I was involved in development of Auto-Focus system in an
industrial Optical Inspection machine (for PCB industry). One of my
first attempts was to understand the AF system and algorithm used by
modern SLR's. So here some relevant points to your question.

The AF system / algorithm in current SLR's is not designed to define the
"main subject" instead it can identify the "most in focus" sensor or the
"most rapidly changing focus" sensor. The "fuzzy logic" algorithm
assumes that if a subject changes focus rapidly - it is the one that the
photographer would like to maintain the focus on it. Different brands
incorporate different "fuzzy logic" algorithms, almost all of them
patented. It was real fun to reed the patents and pain in the ... to
understand.


The AF sensor itself is a kind of small matrix of CCD arranged in
several rows - thus it is more sensitive in one direction than another.
The test for focus is the degree of contrast across the sensor - the
focusing element of the lens is moved till the highest contrast is
achieved.

If you (or other members) have more questions - feel free to ask.

Ze'ev Kantor
zeevk@netvision.net.il


From minolta mailing list:
Date: Tue, 04 Sep 2001 
From: elki9605@yahoo.com
Subject: Re: AF operation

--- In minolta@y..., "Alex Z" alexz@n... wrote:
> Main interest would be to understand algorithm of main subject definition by
> the camera system.

Hi Alex,

try this page 
[Editor's Note: http://www.howstuffworks.com/autofocus.htm]
as a starting point, but don't waste your time trying to completely
understand any autofocus system! The used parameters are too complex
to predict the reaction: AF is coupled to metering, governed by
camera and manufacturer specific algorithms but strongly depends on
object contrast, illumination and (of course) lens focus position.

regards Christian.


From minolta mailing list:
Date: Tue, 04 Sep 2001 
From: mlipphardt@ameritech.net
Subject: Re: AF operation

HowStuffWorks is one of my favorite web sites, but their explanantion
of passive AF is a little dated.  For instance, "mostly sentitive to
vertical lines".  Hmmm.  But the basics are there.

AF systems are not linked to exposure systems.  Exposure systems are
linked to AF systems.  A quibble, but an important one.  The exposure
system does not affect how the AF system works, but the AF system can
definitely affect exposure in Maxxum/Dynax cameras.

Mike
....


From minolta mailing list:
Date: Tue, 04 Sep 2001 
From: "Alexander Koz" alexanderkoz@excite.com
Subject: Re: AF operation

Unfortunately, howstuffworks.com/autofocus.htm does not explain how AF
works in Minolta cameras. Minolta (and others) uses so called
"phase-detection system" in its bodies, not contrast detection which
is discussed on the site. About phase detection system one can read in
August issue of Scientific American, 2000:

http://www.sciam.com/2000/0800issue/0800working.html

Alex.


From leica topica mailing list:
Date: Wed, 29 Aug 2001 
From:  telyt@earthlink.net
Subject: RE: was: Dave Beckerman, now AF versus manual focus

Mark Bohrer wrote:
> Great shot! The horse is beautiful, and every hair is discernible.
> Movement's also parallel to the camera.
>
> There are some shots of approaching pro downhill mountain bike racers I
> couldn't have gotten without AF. I could pre-focus to a spot, and try to
>
> shoot when racers reach that spot, but when they're approaching
> obliquely
> or head-on at 40+ MPH and I'm using a fast shutter speed and limited
> depth
> of field with 200mm or 300mm lenses, I wouldn't get many keepers.


Mark, no doubt AF is handy in these circumstances but it's not as
nessesary as the camera makers (or their marketing departments) would
have us believe.

Dogma has it that AF is required for photos of birds in flight, but I've
found that a top-quality viewfinder and ergonomics to match are all I
need, whether the bird is flying parallel to the film plane or toward me
(at whatever angle).  The photos I've seen that supposedly demonstrate
the value of AF are of birds flying parallel to the film plane, and as
often as not are mis-focussed on the bird's near wingtip leaving the
head and eye blurry.  My pelican series from last December was all done
with a 560mm lens, many with birds flying toward the camera, and none
were tossed due to missed focus.  I also have photos of ducks exploding
off a pond, where I follow-focussed as the birds transitioned from
resting to full flight in a fraction of a second.  In the photos the
pond and the spray from the duck's jumping off the water are out of
focus, while the duck is perfectly sharp (1/500 sec @f/6.8).

With an appropriate design, manual focus isn't as difficult as the
marketing people would have us believe.  Most camera makers have chosen
to invest in AF rather than optimize for manual focus, and we as camera
users/consumers choose which type of system meets our needs.  The choice
you and many others have made to use AF systems is none of my business
but the popular thinking that AF is required for sports and wildlife
photography sounds like dogma where my experience has been that other
design philosophies are also effective.  Each type of system has its
strengths and weaknesses but to say that one or the other is nessesary
(or useless) is more a reflection on the photographer's working style
than anything else.

Doug Herr
Birdman of Sacramento
http://www.wildlightphoto.com


From leica topica mailing list:
Date: Wed, 29 Aug 2001 
From: Godfrey DiGiorgi ramarren@bayarea.net
Subject: AF and MF discussion - The 10% Beyond


Gawds, i'm in a "manifesto" mood. I've been reading and thinking about
these topics too much over the past several months...

I am one of those who does not believe that marketing drives everything in
the universe. I've seen engineering drive a lot of things that marketing
adopts as dogma, through lack of understanding or through the need to
Believe in order to Sell.

Autofocus is an engineering response to a problem faced by many
photographers ... inaccurately focused photographs, whether through
neglect, incompetence, or because focusing conditions are just empirically
difficult. The basic goal of autofocus designs is to provide quick,
accurate focus for the average conditions of most photographs; the
additional goal catering to the action photographer has become to
incorporate predictive focusing capabilities for moving subjects has
become a natural extension of this. No engineer will tell you that an AF
mechanism will *always* focus 100% accurately. No engineer will deny that
accurate targeting and responsiveness are the difficult problems that AF
mechanisms have to surmount. For that 90th percentile photograph that is
most of what most amateurs and pros alike shoot, modern AF systems coupled
with the high quality averagel lenses of today are remarkably accurate and
responsive, produce amazingly good results.

For the 10% beyond that, nothing replaces a super high quality lens
focused with extreme precision by an experienced photographer. It just so
happens that a large percentage of what I and many others on this list are
trying to achieve is in that 10% Beyond category.

Marketing might say that "AF is better than MF"  because they drive more
sales from it due to a higher percentage of accurately focused, pleasing
*average* photographs produced. That's just a marketing rationalization,
not engineering and design ideas that go behind the technology, not the
reason FOR the technology. Sometimes that notion seems to get lost.

AF is similar to the multimode automated exposure systems of modern SLRs
also. These are an engineering response to a daunting problem: for many
years, the professional standard in films were transparency emulsions
which have limited latitude. So many different techniques for exposure
measurement and evaluation came out of the quest for accurate exposure of
these difficult emulsions! But they were necessary ... We didn't need such
sophistication for the relatively broad exposure latitudes of B&W; and
color negative emulsions. Professional photographers demanded improved
exposure evaluation to reduce costs in film and produce results -- to stay
competitive -- and the advantages to the relatively unskilled consumer
photographic market became obvious very rapidly too. Again, Marketing
adopted the technology after engineering drove it and called it "better"
because satisfied customers with well exposed pictures will buy more
equipment, film and processing. That great 90th percentile need is well
served by the plethora of AE systems now available.

Again, our 10% Beyond needs often outstrips the capabilities of modern
exposure automation  systems ... we thrill seekers are looking for things
that exist beyond the norm, for which many times the automation of focus
and exposure simply cannot produce the kind of results that skilled
operation by a thoughtful photographer can.

As we move into the digital photographic era, the mass adoption of
automation systems into the first wave of cameras is natural: that's what
makes them desireable, viable en masse to the consumer users, drives
adoption and profitability which fuel more research and development
dollars. The 10% Beyond crowd is not there yet because the base imaging
technology is still young, not yet capable of returning the results that
the mature and well developed film technology can achieve at a price we
can afford. As the digital technology matures, more options and more
capabilities for the 10%ers will arise. Market dynamics, demand and profit,
will drive what is economically feasible to produce based upon
engineering solutions to problems expressed by the users.

There is space for all of us to be happy. There are uses for AF that MF
cannot easily suffice for, there are situations for which AE makes perfect
sense over manual control of exposure. Conversely, there are lots of times
when manually setting the focus and exposure will deliver results that
automation systems cannot reliably deliver.

What is required is that we not be afraid of change, that we look upon
technological innovation as an opportunity to find new ways to express
ourselves, to accomplish our goals and further our photography. I love my
Ms, I have yet to find an automated or digital camera that becomes so
invisible in my hands, so transparent to my sight, when I am reaching past
the 90% into the 10% Beyond. But as I explore a modern automated SLR
system, I become more appreciative of its advantages and merits, that
which it allows me to achieve which is different from what I would be able
to with manual means. I can also see how fine the design of user interface
to these automated machines must be for them to be useful and achieve that
transparency I love in my M.

Enough soapbox....  ;-)

Godfrey


From leica topica mailing  list:
Date: Thu, 30 Aug 2001 
From: "Ted Grant" tedgrant@home.com
Subject: Re: AF and MF discussion - The 10% Beyond


Has anyone asked what we did before auto focus came to be the ass saving
gizmo for many unskilled photographers of today?

Now that should grab some attention! ;-)

I hate to bring up the "we did it sharp long before" auto focus was a
twinkle in some engineer's eye, but many of us still focus by hand today.
And, we still do get a very high ratio of in focus Leica glass cutting sharp
images shooting sports, dancing girls, flying birds and whirly gigs without
any aids to focus vision. One eyed or not!

Sure we miss some, but I'd put money on the auto folks miss more than the
manual folks on any given day. Personal experience with and without
autofocus and what I see and hear from other pros..... wire service and
sports shooters, that they __"turn off"__ the auto stuff more than they
leave it on!

A thought provoking comment from a pro of many years who started using AF
when it arrived on the scene and has upgraded as new stuff comes along.  "
AF is a good thing, as I get more images sharp out of 36 frames, however,
that doesn't mean I get 36 sharper better pictures!"

Hmmmmm! So my manual focusing R8's and all that glass I own isn't so bad
after all!

Yep I've used auto everything cameras and I thought the auto stuff was neat.
However, my experience was... I became a "lazy technical photographer!"
What I mean by that is........ I just let the camera do the walking through
the exposures and focusing without any thought to the photographic process
in the same manner I did when doing MF!


I found myself with a higher ratio of throw always with AF than without,
maybe  because I accepted the auto stuff  too freely and just let it become
too loosey goosey on technique.  Not saying others get into that mode.

But you can be a good technical fast action photographer, shoot the
Olympics, bikes races, white water rafting, cars on the big ovals and never
use AF once! And still be published with award winning photography!

Just thought you might like a thought or two from the old guy! ;-)
ted

Ted Grant Photography Limited
www.islandnet.com/~tedgrant


From leica topica mailing list:
Date: Thu, 30 Aug 2001 
From: kirk tuck kirktuck@kirktuck.com
Subject: RE: AF and MF discussion - The 10% Beyond


One thing I think everybody is missing on the auto versus human focus
stuff is this:  Sometimes there is not one point that is "the" point
that has to be in focus.  Sometimes we're splitting depth of field
between two objects or people.  Yesterday I shot photos in my kid's
kindergarten class with the 80 1.4.

When I wanted to focuse on one child it was obviously an easy enough
proposition for either type of camera.  BUT when I wanted to split focus
between two kids at slightly different distances using available light
and wide aperatures I had to carefully think about where I was going to
place that slice of focus to keep both kids acceptably sharp.  I used to
shoot with an F5 and I know that I would have gone with the ineria of
the system and just locked in on the closest kid.  Or put on a flash and
go for f8.  With the MF R8 I was able to focus on the first and then
shift focus so that it fell in between both the kids.  Then, at f3.5 I
checked depth of field on the screen with the stop down lever.  Now,
some genius will chirp in that all of this could also be accomplished
with the Nikon, Canon, etc.  but it would require extra steps, locking
AF and then shifting to MF  and then trying to distinguish sharpness on
a screen that's optimized for brightness instead of sharpness.  Then,
when I go back to shooting individual kids I would have to set the
switches back to AF.  My conclusion, borne out by experience is that MF
cameras are faster for photography that requires thoughtful practice for
good results.  They have not yet made AF cameras that can focuse
accurately on the empty space between two objects.

Kirk. 


From minolta mailing list:
Date: Thu, 6 Sep 2001 
From: "Ze'ev Kantor" zeevk@netvision.net.il
Subject: RE: Re: AF operation

It might be because the "film" of the digital camera is an array of CCD
sensors - so why not using them? The only drawback I can see is a slower
response of CCD vs. phase-detection sensors, but they have higher
sensitivity. My guess is that this is the reason for Dynax7's slow AF
but very good performance in low-light conditions. This is my "educated"
guess.

Ze'ev Kantor
zeevk@netvision.net.il



From: Alex Z [mailto:alexz@nogatech.co.il]
Sent: September 05, 2001 
To: minolta@yahoogroups.com
Subject: RE: [minolta] Re: AF operation


It's interesting while modern AF systems in SLRs has been chosen to be
phase-detecting rather then contrast-edge type (is it used today in some
of digital P$S cameras). Any clues ?

Alex


From leica topica mailing list:
Date: Thu, 06 Sep 2001 
From: "Alexander Koz" alexanderkoz@excite.com
Subject: Re: AF operation

My first guess is that phase-detection system allows camera to decide
where the focal plane is, behind or in front of subject, and minimize
hunting.  Secondly, it uses contrast-edge type CCDs as its main
detectors, i.e. it is improved contrast detecting system. Am I right,
Ze'ev?

Alex.



From Nikon Mailing List:
Date: Fri, 23 Mar 2001 
From: ken rockwell kenrockwell@kenrockwell.com
Subject: [NIKON] Focus Errors with Nikkor Consumer Zooms

Hi Ross:
            
I hope I didn't give the impression of "major" focus errors.

I'm unsure if I make it clear, however these focus errors are something a
very careful eye may see at full aperture, but also subtle enough that most
people will probably never notice them in real photography unless they look
for them.

It all comes down to limitations of modern day AF lenses and systems.

Different samples of lenses display different propensities for this 
effect, too.

Stopped down these effects also are insignificant.


They become important if you shoot wide open as I do on 50 speed Velvia.

Oddly, I just got a new 17-35.  It's a fantastic lens!  The sample I had,
however, only at 28mm, would focus a little bit off such that at f/2.8 it
was less sharp than other lenses at 28mm.  I just got a replacement sample
and it appears to be fine.

I hope I haven't distracted people to go off and look for flaws to distract
them from the important parts of photography.  I'll check my pages and try
to put these issues in perspective.

Ken Rockwell


From Nikon Mailing List:
Date: Sat, 24 Mar 2001 
From: "Ed Mathews" itzed@erols.com
Subject: Re: [NIKON] Focus Errors with Nikkor Consumer Zooms

     Well,  being a manual focus fan, I'm also very picky and actually quite
"anal" about AF performance.  And that's actually one of the reasons I
bought a F100.  I've always owned Nikon equipment, but for the past several
years have been shooting mostly with another brand, which I had invested
heavy amounts of money into.  The problem I had with the other brand was
identical to what Ken described, in that some lenses would consistently
auto-focus correctly, and others would consistently not.  I also found that
it was usually the lenses with aspheric elements or glass with high
refraction properties that had problems.  Oddly, the cheaper, less
complicated designs focused perfectly.

     So when I was in the market for a new "pro" level camera, I looked at
the other brand and found that with my lenses, that pro body exhibited even
greater focusing errors than my old body.  So I looked at and decided on an
F100 instead, and took a chance that what I ordered would focus well with 
my leftover AF (non D-type) Nikkors.  I was prepared to send the body back if
it did not meet my standards.

     I've done test after test with this new F100 body, and I am pleased as
can be with the AF performance and my lenses.  I can find absolutely no way
to improve the focus manually using the following lenses:

50mm F1.8 AF (non D)
85mm F1.8 AF (non D)
24mm F2.8 AF (non D)
Sigma 28-105 F4-5.6 AF (D version)

     However, I am soon in the market for a telephoto zoom, and I recognize
that it is indeed quite possible that focusing errors can exist with any
particular AF body and lens combination, so I will indeed be quite picky
about what I purchase, and will test any lens I consider thoroughly before I
accept it's performance with my F100.

Thanks,
Ed



From: Anders Svensson anders.-.eivor.svensson@swipnet.se
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Camera robustness: do they make 'em like they used to?
Date: Fri, 30 Mar 2001 


ShadCat11 wrote:

> Perhaps in optical quality, but the mechanics are simply not up to the MF
> versions.  AF Nikkors are well finished, but wear out faster.  I have mostly MF
> versions, AI and AIS, and a couple of AFs.  Some of the MFs are 20+ years old,
> none younger than 15, all mechanically sound after considerable use.  None have
> required repair of any kind.  The AFs, OTOH, are of recent vintage and under
> similar use, show signs of loosening up.  Both have needed repair.

There is, ofcours a easily understandable reason for AF
lenses to be less solid. The tiny AF motor must be able to
focus them, so they can't have solid, large bearing areas
(read: helicoid) and a smooth, nice feeling movement (read:
tight tolerances).

It is part of the price we pay for fast, precise AF.

That said, I compare the Nikon first generation AF lenses to
the newer ones, and if anything, the problem has got worse.
I use some of the older AF lenses like the 35-70 f/3.3-4.5
and the first version 28 f/2.8 AF lenses in manual mode on a
EM sometimes. These lenses were considered "budget" in their
days, but compared to the last version of the 35-80 cheapie,
they are marvels of mechanical sturdiness...

Anders Svensson
mail: anders.-.eivor.svensson@swipnet.se




From: Tony Polson tony.polson@btinternet.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Camera robustness: do they make 'em like they used to?
Date: Fri, 30 Mar 2001 

Anders Svensson anders.-.eivor.svensson@swipnet.se wrote:

> There is, ofcours a easily understandable reason for AF
> lenses to be less solid. The tiny AF motor must be able to
> focus them, so they can't have solid, large bearing areas
> (read: helicoid) and a smooth, nice feeling movement (read:
> tight tolerances).
>
> It is part of the price we pay for fast, precise AF.

Most of the smooth feel to the focusing ring of an AIS Nikkor comes from
the lubricating grease.  If you come across a rare example of a Nikkor
where the grease has almost gone, the focusing action is nearly as loose
as that of a typical AF Nikkor.

I recently saw an extreme case where a 75-150mm f/3.5 Nikon Series E
lens had its focusing/zoom action transformed by a CLA.  The zoom/focus
ring was very loose and could be zoomed in and out merely by tilting the
lens.  The lens was relubricated with the correct specification grease
and now has a firm and smooth zoom/focus action, just like new.  The
owner had been ready to trash the lens after 20 years' service despite
its optics being unmarked.

The point is worth making that Nikon Series E lenses were derided in the
1970s and 1970s for their inferior build compared to AIS Nikkors.
That's because some plastics were used in their construction.  It's
ironic, because the Nikon Series E lenses have better build quality than
many Nikon AF lenses including some that are unashamedly aimed at
professional users.

--
Tony Polson



From: Anders Svensson anders.eivor.svensson@swipnet.se
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Camera robustness: do they make 'em like they used to?
Date: Fri, 30 Mar 2001


Tony Spadaro wrote:

>     If lighter lenses are more delicate we are getting advantages as a trade
> off - and quite frankly I'm not so damn sure they are delicate at all. What
> is the big objection always stated - It FEELS sloppy - isn't this the same
> as "Eeoo Plastic - Nasty nasty."

One area where sloppiness do count is when the tolerances
are so sloppy that lens groups wobble. When I shake my
(admittedly very cheap) 35-80 Nikkor, the front group
wobbles independently of the aft group. This must be bad,
optically.

--
Anders Svensson
mail: anders.-.eivor.svensson@swipnet.se





From leica mailing list:
Date: Wed, 06 Feb 2002
From: Jim Brick jim@brick.org
Subject: [Leica] APS out ?

BJP Quote

"One of the world's leading camera manufacturers is switching its
research and development team away from the Advance Photo System format
in favour of digital.

The decision by Minolta to stop developing new APS camera models
provides the first sign that the 24mm format, introduced just over five
years ago, may be entering its first death throws."

Jim





From minolta mailing list:
Date: Wed, 16 Jan 2002
From: "giuseppe stama" giuseppe.stama@tiscalinet.it
Subject: Re: Reversing  a lens

Hi, Manfred

Look at this link in the MUG page

6.2.1 How to disable the lens mount check

http://www.sds.com/mug/af-tips.html

Here You can find what you want.

And ... Manfred, I have bought the HAMA 9544/5 reverser adapter for 55mm
filter thread, thank you again for your useful information. Is very simple
to use, and the f-stop ring is very precise. And I am very happy that is
on offer, only 7.5 EUR.

Ciao Giuseppe
...



From Nikon Mailing List:
From: "Phil Considine" philcons@bigpond.com.au
Subject: RE: [Nikon] Consumer vs. Prosumer vs, Pro
Date: Fri, 8 Mar 2002 

Let me spell it out.  Hunting is less a factor of glass (or Fstop up to a
point) than of light and contrast.  So any AF lens will hunt, in situations
of low light, of low contrast or confusing lines on a subject (like a
venetian blind).  If NIKON say AF is optimal at F2.8 they are doing no more
than stating the obvious and they carefully word it to mean optimal rather
than reliable. They also say a given camera will support AF up to F 5.6 they
don't say AF stops at F5.6. So with high contrast and lots of light, I can
get my 300 F4 to AF with two 2x extenders - I don't say that is practical or
desirable, only possible. ..I can also make my 85mm 1.8 hunt in low contrast
situations. It doesn't mean anything other than for any given condition and
camera, AF works or it doesn't and fast lens only extend these conditions by
allowing a few stops more light.



From: eos10fan@hotmail.com (dan)
Newsgroups: rec.photo.equipment.35mm
Subject: FYI: Minolta ditches APS for digital
Date: 19 Feb 2002


http://www.bjphoto.co.uk/cms/words/news_and_news_features/22.shtml

"One of the world’s leading camera manufacturers is switching
its research and development team away from the Advance Photo System
format in favour of digital.
The decision by Minolta to stop developing new APS camera models
provides the first sign that the 24mm format, introduced just over
five years ago, may be entering its first death throws. Laurie Moore
from Minolta UK told BJP that the company has ‘no plans to
introduce new products into the range’. The company’s
current stock – including many higher specification models
– will be available for a further 15 months."


http://www.bjphoto.co.uk/cms/words/news_and_news_features/22.shtml

More info at the above link.

May the Light be with you.Y
-----
dan



From hasselblad mailing list:
Date: Mon, 18 Mar 2002 
From: Tom Just Olsen tjols@online.no
Subject: Re: [HUG] the death of Hasselblad (all MF)

Mark,

"Are things this bad everywhere..?"

- Not at all.  Scandinavia, possibly the part of the world with the
relatively highest sales of digital equipment to pro photographers
(according to a newspaper org. magazine), sales of Hasselblad is going
well. They are just excellent together with the new Kodak pro backs (and
other excellent digital backs). Surely, the weight of new equipment
investments among pros might have been into digital stuff lately,
possibly with marginal effect on buying of new cameras and lenses.

Analog large format is not dead at all.  Nor is digital established as a
high end quality provider yet (- whatever teh digital shooters say). A
good example is a news interview given by the the author of a picture
book on the royal wedding here in Norway last year.  She claimed that
'hardly any' of the 'digital picture raw material' made it to the book
'since they were not good enough'.  It hit the 'digital photo gear
miljeu' here in Norway as a bomb-shell and quieted down the digital v
analog debate for quite a while.

My neighbour daughter is studying 'media' in England and had a chance to
attend a shooting of a whiskey commercial for TV.  Imagine, some ice
cubes are thrown into a glas of whiskey and cascades the fluid around:
The 'whiskey' was glycerine with artificial colour, the ice cubes, some
specially made plastic cubes. One should think that this would be a
typical 'digital application', but no.  The camera?  A 23 x 23 cm ex.
spy camera from the Vietnam war, the only one of it's kind for
commercial use, speeded up to double speed, - with an enormous use of
'special made Kodak film', some two pallets of it, as a result.  This
was the only tool that could give the 'very high resolution', - for a 28
-to 32 inch TV screen, demanded of the whiskey destillery. The heat from
the lamps illuminating the sceene forced the crew to 'run about half
naked', my neighbor's daughter claimed (what is she attending, over
there??) after half a days work.

As for AF, it is a matter of price and cost efficiency. For
action-shooting it might give you a small advantage, but it is obvious
(through tests and experience) that AF gives only marginally more sharp
pictures than 'the old manual way'.

Of the same reason as many, I changed to AF (from Canon FD ot EOS/EF)
because of having problems focusing when my eye sight grew worse when
passing 50.  What was really good about the change was the much brighter
view finders of the EOS3 to the old A1. 'Bad focusing' has NEVER been a
problem with my Hasselblad shooting after changing to Accute Matte
screen. Deffinately the strong point with the new 200-series is just
'very bright viewfinders'; the absolutely the most important thing if
you want to focus right.

Much is 'focused' (sic) on AF speed, these days. Reliablility should be
more of an issue.  Tests (Dimage Chasseur) show that both Canon and
Nikon, - and the best of them, really haven't that much more 'AF
reliability' than you would manage yourself.  In the most simple of
applications, it is closer to 50% than they would like to tell you. That
is 'focusing-accuracy by flipping a coin'!  It is in 'some' extreme
action-situation that AF do really get better, - sometimes.

Still; the market wants AF and Hasselblad (or rather Carl Zeiss) do
indeed have it up their sleaves. The obstacle (like all camera producers
have to face) is to bring it to the market to a price that the customers
are willing to pay for it.  Obviously (and as confirmed with Nikon and
Canon), if you are going to provide AF 'to the same price as manual',
you have to sacrefice something else; like resolution power or 'general
sturdiness' (which is all to high for most Hasselblad/Carl Zeiss
products anyway).  So, what we are going to get is new Carl Zeiss AF
lenses and ditto camera bodies with a 'life expectancy' of 10 - 15 years
to that of 35 years + + today.  That would be the most profitable
solution.  Much cheaper digital backs is on it's way too.  There will be
several on the market next year to 'about 5000 dollars' as well as even
better 'high end/high price' tools.

I think digital is a immense step forward in photography, but I am not
at all sure that AF is.

Tom of Oslo


 Kronquist wrote:
>
> "I know what you mean about Hasselblads being slow, the market is flooded
> with them.  I am on most of the professional photographers list-servs, and
> the consensus is that within another six months most pros will have dumped
> them and bought the new digital cameras.  You can make a lot more money for
> a fraction of the work.  It is doubtful that any professional will be doing
> medium format film several years from now.  Even if you use RVP film in your
> hassleblad you cannot get the quality of the new digital, and whatever you
> get with a drum scan from film is going to be three times the file size with
> less image information than a born-digital file.  Most people can't afford a
> lot of drum scans, and the 4000 dpi slide scanners for the medium format
> film cannot compare with a born digital file."
>
> The cases are full at local dealers. Sales seem to have slowed to a crawl...
>
> One local camera store guy said it's been 9 months since he sold a Blad lens
> or body and 2 YEARS since he sold a Mamiya or Bronica. and that Large Format
> sales are even worse...
>
> Are things this bad everywhere?
>
> Mark


From minolta mailing list:
Date: Mon, 29 Apr 2002 
From: "ctgardener" ctgardener@yahoo.com
Subject: Re: How Autofocus Cuts Your Lens Potential Resolution by Half

 In Minolta@y..., Erik Stiegler erik@m... wrote:
> You're being taken for a ride. That page and the Pop Photo article are severely flawed.
>
> The Pop Photo "tests" that claim higher resolution for manual focus lenses are rigged in favor
> of the manual focus lenses. Pop used viewfinder magnifiers on the manual focus lenses, giving
> them a clear advantage. How many photographers even own a viewfinder magnifier?

I do !  Two, actually :)  And they're for use with my AF cameras and
lenses !  There are times when I can focus manually far better than
my camera can focus automatically, and vice versa.  An AF camera
gives you the option ... MF doesn't.

- Dennis
...


Date: Tue, 08 May 2001
From: "Mxsmanic" mxsmanic@hotmail.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: How about manual focus?

"Amy Hughes" amyhughes@my-deja.com wrote

> 1) If you get an AF camera and want to manually
> focus, turn off AF. But if you get a MF camera
> you can't AF.

A lot of AF lenses are extremely unpleasant to focus manually, however.
The travel of the focus ring is very small (because it makes AF more
efficient), and it often has play or a cheap feel to it that makes
adjustment difficult.  The resistance of the drive mechanism works
against you, too.  The exceptions are some lenses using piezoelectric
drives (USM, AF-S, whatever you want to call it), which allow not only
MF override of AF, but also may have extremely smooth and positive MF
feel.  The AF-S lenses I've used are all a pleasure to focus manually,
but the other kinds of AF lenses are very frustrating.  Neither has the
ultimate smoothness of a purely MF lens, though.


From: drfleming@altavista.com (DFleming)
Newsgroups: rec.photo.misc
Subject: Re: Canon lenses with no depth of field scale
Date: 29 Apr 2002

"Robert J. Wood" robert@robertjwood.net wrote
> I have no idea why the good people at Canon choose to not include depth
> of field/distance information on their lenses.  This completely
> eliminates the option of prefocusing and using hyperfocal distance,
> etc.

There are a couple of reasons why many modern lenses don't have the
depth of field scales.

First, it is difficult to put a depth of field scale on a zoom lens.
Because depth of field is a function of focal length, the depth of
field marks change when you change focal length.  "One-touch" zooms,
on which the barrel slides forward or back to zoom, sometimes have
scales.  I don't believe that Canon makes one-touch zoom lenses.

Second, the throw (amount of rotation) to change focus is short on a
modern auto-focus lens, in order to enable fast auto-focus.  On many
of these lenses, the distance scale is so short as to be useless.  For
example, the Canon USM 100mm macro lens has only about a 5 degree
rotation to change focus from infinity to 5 feet.

> Does anyone know of an online depth of field chart for Canon lenses or
> any other solution that could help me get around this?
>

Canon has tables of depth of field and hyperfocal distance for most of
the Canon lenses at:

    http://www.canon.com/camera-museum/camera/lens/f_lens.html

(Select a type of lens, and then select a lens.  Links to DOF data are
at the bottom of the lens specification pages.)

Here's a link to two free depth of field calculators:

    http://www.dofmaster.com

The DOFMaster program for Windows can print depth of field scales
(circular slide rules) for use in the field.  The DOFMaster LE program
is for Palm devices.

DOFMaster was designed to emulate the depth of field scales on lenses.
You can duplicate the Canon DOF data with DOFMaster by using a circle
of confusion in the range of 0.030-0.033mm.  It seems to vary from one
lens to the next.

--
Don Fleming
http://www.dofmaster.com


From minolta mailing list:
Date: Thu, 02 May 2002 
From: "ctgardener" ctgardener@yahoo.com
Subject: Re: Autofocus?

--- In Minolta@y..., "tedshaw" tedshaw@a... wrote:
> I shoot mainly landscapes and horse/people sports on an old Pentax ME Super
> but am seriously thinking of buying the Dynax/Maxxum 7. However, because
> I've never used an autofocus camera I'm looking for some advice:
>
> 1. Is autofocus accurate? I've heard that resolution can be lost due to
> inaccurate focusing.

AF is accurate, but when focus has to be critical, there's no way for
the camera to know exactly where you want to focus ... I'm thinking
of photographing an animal with shallow DOF where the camera will
focus on the animal just fine, but you want to tweak it to get the
eye sharp - the eye is just too small for any of the sensors.  The 7
is particularly nice because you can let the camera "rough focus" on
the subject, then you can easily tweak it with DMF.

For what it's worth, I shoot most of the time in manual focus,
because my subjects simply don't demand AF - still shots - scenics,
landscapes, etc.  For macro work, in particular, manual focus is
nearly necessary because DOF is usually so shallow.  I also use a
viewfinder magnifier a lot to help me with critical focus in these
instances.  For my scenics, I use DOF preview on the 7 frequently,
and often end up focussed on nothing in particular ... so I know I
wouldn't get the same results with AF in some cases.  For other types
of photography - any kind of action, vacation photos, pretty much
anything not on a tripod, I use AF and believe that in those
circumstances, it does a better job than I would by focussing
manually.  I guess that's my method, now that I think of it - when
using a tripod, I focus manually; when shooting handheld, I use AF.


> 2. Is it necessary to let the camera focus first before moving the camera so
> that the object isn't in the center of the frame?

Not necessary, though that method works fine and keeps you in
control.  Wide area focus is pretty good at identifying subjects, and
you also can select a particular focus point.

> 3. Does the manual focus work as well on the 7 as it would on a
manual
> camera? Does it feel right?
On Maxxum cameras, there's a linkage between the motor in the camera,
and the lens, that involves a screwdriver-like blade engaging a slot
to turn the lens.  On most Maxxums, switching to manual focus
disengages that linkage.  On the 7, to enable the direct manual focus
(DMF), there's a clutch mechanism that keeps the linkage engaged
without harming the motor in the camera.  There's a little more
resistance this way, but most AF lenses I've used focus more freely
(in manual mode) than the manual focus lenses you're probably used to
anyway.

> 4. Is there anyone who regrets his or her move to autofocus for any
reason?

I had some regrets with my older (10+ year old) camera, because the
controls weren't very intuitive (but not enough regrets to want to
switch back).  With the 600si and the 7, none whatsoever.  The
advanced metering and flash capabilities on any Maxxum in the last
ten years alone are worthwhile !

- Dennis


From nikon mailing list:
From: "rollin" rollin@natuurfotografie.be
Date: Fri, 3 May 2002 
Subject: [Nikon] delay times

Hello Nikonians and others,

I wrote an artikel on my website about the shutter lag-times of the F100 and
F90x. I'm a photographer of flying bats and insects, so this interested me.

The shutter lag of the f100 is 56 ms, the F90x is even worst at 86 ms, this is
1/11 th of a second!!

Did you know the shortest flas burst of a SB28 is 1/12345 th of a second?

You can see more details at my site

http://home2.planetinternet.be/rv047190/

go to the English content page and you'll find a link at the bottom of the
page.

Rollin
....


From: "R.C. Johns" nospam@att.net
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: Rnd 2: Pentax 645N  vs Contax 645
Date: Wed, 12 Jun 2002 



First of all, I wouldn't think that the fact of the 645N using inserts only
rules out digital backs. In fact, I read somewhere on the Web (perhaps a
more reliable source that a Usenet group :-/ ) that some of the design
changes in the 645 NII were made precisely to facilitate use with some
future digital back/insert/device. So I wouldn't rule out the Pentax 645N on
those grounds alone, though I'm not quite sure why AF would matter, given
your interests. As noted by a previous poster, the Mamiya non-AF 645 system
is worth considering. The Mamiya 120 f.4.0 macro has a good rep. Both Pentax
and Mamiya have lots of used goods available; the Contax has virtually none.

Just before reading your post, I was about to ask if anyone had any
experience with the relative tracking performance of the Pentax/Contax AF
systems. I realize it won't be up to modern EOS standards; just handling
tasks like slowly moving people. I have poor eyesight and pretty much need
autofocus now.

Thanks!

"Eric Stral" estral@ekc.com wrote...
> Hi all.  Thanks in advance for all your comments.
>
> I am about to purchase a 645 autofocus system, I know I need removable
> backs, for future digital back, so the Pentax 645 is no longer a
> consideration.
>
> I need help deciding between the Mamiya and Contax systems.
...


Date: Thu, 25 Jul 2002 
From: David Albrecht davidwMork@writeme.com>
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Lens dilema


My problem with non-OEM lenses is that the camera manufacturer is busily trying to
break the compatibility of non-licensees when they come out with new bodies. Further,
you often sacrifice focusing speed and the relative quiet of USM lenses vis-a-vis the
Canon lenses and frequently some amount of optical quality.  The EOS-3, for instance,
was incompatible with every non-OEM lens I owned.  Since then I decided it wasn't
worth the price difference to potentially have to go and rebuy a relatively expensive
lens to use it with a new body.  In my case it was the Sigma 28f2.8 which was upgraded
for free, and the Tokina AT-X Pro f2.6-2.8 and AT-X 80-200f2.8 which were not.

Dave

Jodee wrote:
> I need some help!
>
> I own several Canon EOS 35mm bodies, and have always purchased high quality
> Canon lenses.  As my hobby is getting terribly out of control (and I love
> it!)  I have to start to question spending the extra cash for name brand
> specific lenses.
>
> I am looking at a F 2.8 Tokina AT-X m 100mm lens for a backup portrait lens,
> but am somewhat apprehensive about making the leap :-)
>
> I figure that I can't be the only one who has winced at the thought of
> spending more than necessary on lenses.  Can anyone here relay their
> opinion, experience or advice regarding this conundrum?
>
> Thank you very much in advance!



From: T.P. tp@nomailthanks.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Leica is so overpriced.
Date: Thu, 04 Jul 2002


stking+++@duke.edu wrote:
>
>From my point of view, the M6's meter may be extremely accurate,
>but is also as primitive as you get.


Primitive is all you need.  Anything more, and you might as well get
an automatic camera (or someone else!) to take your pics for you.

I question the high percentage success you put on your auto-everything
SLR's metering system.  If you are getting such a high success rate,
you must be shooting almost entirely with negative film and/or in
straightforward lighting conditions.

My own experience of some of the so-called "very best" auto exposure
systems is that they rarely work well in difficult lighting, certainly
for less than 50% of the time.  And when they don't work, they don't
work in a big way and - more to the point - you have little hope of
knowing how far out they are.

In most situations, especially those with difficult lighting, using an
incident light meter takes away the guesswork and gives you one single
repeatable reading of the light falling on the subject.  And that's
it.  With reflected light readings you have a lot more work to do, and
you need knowledge in order to get it right.

Realising that is the key to success with the M6(TTL) built-in meter.



From hasselblad mailing list:
Date: Tue, 23 Jul 2002 
From: Anthony Atkielski anthony@atkielski.com
Subject: Re: [HUG] Auto Focus or Focus Confirmation

Beau writes:

> I guess that's why I'm often drawn to AF lenses.
> But if and when I do get things right, the HB
> sure is worth it.

AF is one of the best things to come along in photography in decades, but it
is not without pitfalls.  AF focuses accurately on whatever it is pointed at
... but making sure it is pointed at the right thing can be almost as
difficult as focusing manually, in some situations.  Sometimes it focuses at
the wrong moment (because you briefly released the shutter button), or it
cannot decide which of two very tiny elements in an image at greatly
different distances deserves the focus, and so on.  And some cameras will
not fire until the AF says the image is focused, and sometimes you lose a
shot.

For telephoto action shots of skaters in mid-jump a few days ago, I used the
AF to focus on an object at the distance where they would be jumping--and
then I shut the AF off and shot like that.  Had I left it on, it would have
tried to refocus every time I pressed the shutter, and more often than not
it would spend time deciding how and where to focus, causing the shot to be
lost.  Since the focus plane wasn't going to move, I didn't need this
aggravation.

AF is also a problem when you have multiple elements at different distances
and you need to rely to some extent on DOF.  Usually it's better to focus
manually and then carefully fit things into the DOF; sometimes I let AF hit
some intermediate spot so that the DOF covers the range I want, but it's a
delicate proposition.

> It's certainly not the fault of the camera - I
> couldn't believe it when I first looked thru' my
> HB viewfinder and saw how bright it is!

The WLF on the 'Blad is a pleasure to use.  Like those tiny LCD screens on
the digicam toys that the tourists use, except that my screen is bigger, has
a much sharper and clearer image, and requires no batteries!

> My mom's old TLR Rollei was the last MF camera
> I had picked up and man, what a difference 4
> decades makes!

I used an old Rollei some days ago.  The viewfinder was really dim.  Not
sure if that was because of a slow viewfinder lens, or a dim focusing
screen, or what, but it was very dark compared to my 'Blad screen.

> Yeah, I recall muttering under my breath that
> they sure put the hassle in Hasselblad.

It's not so bad.  And you forget the hassle when you see the results.

I have a night shot taken from a tripod on my site.  In the Web version, you
can see the gleaming lights of shops in the far distance.  But in the
original slide, not only can you see the individual shops, but you can read
all the signs in the windows!

> Yep, that's a good point!

A lot of people consider primitive function a drawback, but I see it as an
advantage--at least in situations that require nothing more complex.  I
still haven't gotten used to the fact that I can put my Hasselblad away in
the back without "turning it off"; every other camera I have (even the
Leicas) has _something_ that needs to be turned off before it is stored.

> But I've noticed that in my current state of
> ineptitude, if I spot a ray of fleeting
> light, I just might as well pull out the 35mm.

Me too ... at least then I'll get the shot.  Unfortuately, I'm still a bit
depressed by the thought of how the same shot would have looked in MF.
Especially for stuff that requires details, like landscapes, cityscapes,
group shots, etc., the Hasselblad results are astonishing.  My best Leica
lens produces pin-sharp images on film, images so clear that you feel you
can walk right into them ... but there's no getting past the limitations of
the smaller negative.  (FWIW, the Zeiss glass on the 'Blad appears to be
pin-sharp, too, although I've not yet examined it extensively.)

> For example, I find bracketing useful - because I'm
> just not that good - and that too can take quite
> a bit longer.

If you have the time, you can avoid bracketing by metering very carefully.
For night shots, I meter extensively with a spot meter, until I can come up
with an exposure that will squeeze as much of the interesting stuff as
possible onto the negative.  With care, I only need one shot, and that shot
will be perfectly exposed.  But it takes ten minutes per shot, minimum, it
seems.

> True. It's just that if I see a 35mm slide that
> turned out well, I think "Man! That would've looked
> SO much better on the Hass!"

Same here.  This is one reason why I stay away from large format.  I can't
afford to be spoiled by something even larger.  And MF is really more than
good enough for everything I've done up to now, anyway.  Indeed, 35mm is
good enough for 90% of my work at least; but when I need MF, I need it
badly.

> Another area I'm having a hard time adjusting to
> is going from rectangular to square framing. I
> never *thought* square before.

Thus far, I've found that a square frame is no more or less convenient than
a rectangular frame.  It does have the huge advantage of not requiring any
90-degree rotations.  In any case, while some subjects don't fit very well
into a square frame, I've found that other subjects fit perfectly into a
square frame (whereas they never fit very well into a rectangular frame).
And a great advantage of MF is that you can crop to rectangular and still
have a very nice image, whereas cropping 35mm to square sacrifices a lot of
resolution because the negative is already smaller.



From hasselblad mailing list:
Date: Tue, 23 Jul 2002 
From: Tom Just Olsen tjols@online.no
Subject: Re: [HUG] Auto Focus or Focus Confirmation

Anthony,

OK, that one.  I have an even better system on my EOS3 with a red square
(out of 24) lighting up to show what the AF has 'found' as contrasty
anough to focus on.

I have used my father's EOS300 (a cheap and rather 'plasticy' SLR
camera.  It has AF alright, but no 'indicator'.  Which was a relief in a
way.  You simply had to consentrate on 'getting the image sharp'. Which
is the whole point.

AF is wastely overexagerated with a reliability far below expectations.
Nor can I remember having problems with focusing with my Hasselblad.
Even though my eyesight is getting worse. I am so totally satisfied with
it's bright (waist level) view finder.

What I 'want for Chrismas' out of the Hasselblad product development is
a new and cheaper 205 with a few different light measuring alternatives.
Like spot.

And an improved pro-shade that can 'manipulate' filters better.

Tom of Oslo

 Atkielski wrote:
>
> Tom writes:
>
> > What is a 'electronic focus confirmation'?
>
> A light or other electronic display indicator in the viewfinder that is
> turned on when the AF circuits detect that the image is in focus.  On my F5,
> for example, there is a little green dot outside the image frame that comes
> on when the AF feels that the image is correctly focused.


From: "Skip" shadowcatcher@cox.net
Newsgroups: rec.photo.equipment.35mm
Subject: Re: The worst SLR ever?
Date: Fri, 30 Aug 2002

There, that one has my vote, too.  I'd forgotten about the EF-M.  A manual
focus body designed to work only with autofocus lenses.  Like you said,
"Why?"

> Well if it isn't the worst, then the most stupid is the Canon EF-M -
> huge compatibility problems and never answered that most important
> question - WHY?



From: T.P. t.p@noemailthanks.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: The worst SLR ever?
Date: Fri, 30 Aug 2002

"Skip" shadowcatcher@cox.net wrote:
>There, that one has my vote, too.  I'd forgotten about the EF-M.  A manual
>focus body designed to work only with autofocus lenses.  Like you said,
>"Why?"

It was so Canon could appeal to a key market and sell them EF lenses.

The market consisted of those students of photography whose teachers
insisted that they use only manual focus cameras for their
assignments.  Without the EF-M, students would have bought cameras of
brands other than Canon.


From: haijack@onr.com (RD)
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: Medium Format vs. 35mm
Date: Fri, 13 Sep 2002

rmonagha@smu.edu (Robert Monaghan)
wrote:

>Many of us use DOF scale marks from 1 or 2 stops more
>conservative settings to ensure the subject is really crispy ;-)

Yeah, crispy, that's the ticket!!

Seriously, that's really good advice for anyone. I had a showdown with
my AF SLR (Nikon) regarding the AF/MF issue about a year ago. Once I
realized the significant improvement that was possible, I turned off
AF for good. Of course, then I discovered my manual focus skills (and
my eyes) weren't quite up to the task. The non-changeable focus screen
seemed a sore spot, so I bought but then sold two manual bodies (also
Nikon) when their screens turned out to be no better. I finally solved
the problem through several months of intense practice, forcing myself
to apply better concentration while focusing, learning to focus
faster, and by closing the aperture two or three more stops than
usual. I'd gotten into the habit of doing just the opposite, opening
my lenses unnecessarily, and the two or three I use most are just too
fast for that. Closing things down exactly the way you've suggested
still pulls me out of the fire occasionally when I haven't placed the
focus quite where I intended.

It's too bad I didn't realize the AF shortcomings sooner. I shot for
nearly a year in mainland China right after I bought the camera, but
have only recently begun enlarging my favorites. It's a great
disappointment to realize that many are too soft to deserve
enlargement even to 8x10. It's been a hard lesson.

Of course, then there was the other foreigner I met there, the one who
had all his slide film developed as C-41.  :(

JL



Date: Wed, 25 Sep 2002 
From: Tom Just Olsen tjols@online.no
To: hasselblad@kelvin.net
Subject: Re: [HUG] Hasselblad H1

Anthony,

I agree with you. I see not the big advantage in AF anymore (after
having switched from Canon FD to EOS).  And certainly not on any MF
equipment.  It makes it all to heavy.  Nor is AF reliable, - a very
little talked of issue. With AF; still you have to check thoroughly that
the AF has focused on the right thing.

Tom Just Olsen


 Atkielski wrote:
>
> Austin writes:

> > Personally, I think AF for MF is silly...
>
> I suppose some applications of MF can use it, but I have to admit that just
> about everything I've shot with MF has been in situations where there was no
> particular rush to focus, and AF really would not have changed anything.
> When you spend ten minutes just making sure the frame is exactly horizontal,
> you don't need split-second autofocus.
>
> I wonder if we'll ever see AF for LF.
>
> By the way, does anyone know if pro camcorders are using AF?  Last time I
> was into video (some years ago), they were not, and I suspect that they
> still aren't, but I was just wondering.


From hasselblad mailing list:
Date: Wed, 25 Sep 2002 
From: Jim Brick jbrick@elesys.net
Subject: Re: [HUG] Hasselblad H1 AF

 Tom Just Olsen wrote:
>I see not the big advantage in AF anymore (after
>having switched from Canon FD to EOS).  And certainly not on any MF
>equipment.  It makes it all to heavy.  Nor is AF reliable, - a very
>little talked of issue. With AF; still you have to check thoroughly that
>the AF has focused on the right thing.
>
>Tom Just Olsen


AF lenses, when used in AF mode always have less resolution (lp/mm) than
the same lenses manually focused. This is because AF cannot achieve
critical focus. If it does, it is just luck.

Focus is typically achieved by digitizing the analog signal from a CCD
sensor and creating a histogram from the digitized result based on contrast
differences. As the focus gets closer, the histogram center spike gets
larger. When it passes through and starts to get smaller, then the AF
system backs up the number of steps it went past the high point. The
problem is that there is considerable slop in the focusing that produces
the high point. A range + and - from the critical focus point that allows
electronic focus to think it is there.

There is no solution for this. Other than using your eye and brain to do
manual critical focusing.

And... AF frequently cannot focus on the very thing that you want to focus
on. It cannot see it. There has to be a contrast line between what you want
to focus on and the surrounding area. But if this line runs in the opposite
direction of the how the CCD focus sensor is positioned, you are out of
luck again.

Many of the latest AF systems have attempted to fix these problems.
Orientation is the easiest to fix. Having little or no contrast between the
focus point and the surrounding area is almost impossible to fix.

I played with a Contax MF AF camera a while back. I tried to focus on a
Plexiglas magazine holder, from the side, on the counter at KSP. It was
holding View Camera magazine. The AF hunted forever. We all had a good
laugh. It took about 1/2 second to manually focus on the edge of the
magazine holder.

I believe that the H1 will sell very well. It has all of the features that
wedding (and similar) photographers really want. Auto everything. Auto
exposure, auto flash and auto flash fill, auto focus, 32 frames per roll,
interchangeable backs with an LCD that tells what's in the back and how
much is left, among other things, motor, hand grip, remote, seamless
integration of digital, etc, etc, etc...

My dealer, who sells more Hasselblad equipment west of the Rockies than
anyone except Samy's, say that they can sell the h*** out of these things.
And I believe them.

Me... Im a square. I have enough trouble dealing with my rectangular 35mm &
4x5!

Jim


From hasselblad mailing list:
Date: Wed, 25 Sep 2002 
From: Anthony Atkielski anthony@atkielski.com
Subject: Re: [HUG] Hasselblad H1 AF

Jim writes:

> AF lenses, when used in AF mode always have
> less resolution (lp/mm) than the same lenses
> manually focused. This is because AF cannot achieve
> critical focus. If it does, it is just luck.

AF is quite capable of focusing better than any manual focus system operated
by a human being.  However, most production AF systems are not this precise,
mainly to prevent them from constantly hunting for perfect focus.  A
too-precise AF system will adjust itself continuously just because of the
subject's movement in breathing or pulse.

> Focus is typically achieved by digitizing the
> analog signal from a CCD sensor and creating a
> histogram from the digitized result based on
> contrast differences.

Not so.  High-end AF systems use an electronic rangefinder.  The subject is
sighted through opposite sides of the lens, and the images thus obtained are
examined separately.  When they are aligned, the subject is in focus.  When
they are misaligned, the subject is out of focus.  The direction of the
misalignment indicates in which direction focus must be adjusted, and by how
much.  They are very fast, and very precise.

> There has to be a contrast line between what
> you want to focus on and the surrounding area.

There has to be contrast on the target.  The surrounding area doesn't
matter.

I've had AF rangefinder systems hunt excessively on low-contrast targets.  I
still resort to MF sometimes in consequence, especially with telephoto
lenses.



From hasselblad mailing list:
Date: Wed, 25 Sep 2002 
From: Anthony Atkielski anthony@atkielski.com
Subject: Re: [HUG] Hasselblad H1

Tom writes:

> With AF; still you have to check thoroughly that
> the AF has focused on the right thing.

Yes.  I've been bitten by that many times on my F5--and the F5 has some of
the best AF you can find on any camera.  But all it really does is turn the
focus ring for you (quickly!).  You still have to look very carefully at the
image to see if the AF really agrees with you on what should be in focus.
With telephoto lenses, it gets really delicate (the AF-S 80-200 has a collar
with buttons to stop AF for exactly this reason).




From: "ROBERT BELLIN" CINDRAROB@ATTBI.COM
To: contax@photo.cis.to
Subject: Re: [Contax] New Hasselblad H1 645 Autofocus
Date: Wed, 25 Sep 2002 


When Kyrocera proposed an autofocus camera,German Ziess balked and said do
it yourself.So was born the AX.Zeiss didn't want to compromise the quality
of the lenses by going autofocus.They left it up to the Japanese Zeiss r/d
team .The G1 and G2 were the same way.

 IMO the Contax 645 was designed and produced tis way.

 Hasselblad has had a successful relationship with Fuji(XPAN),and
Rodenstock(FLEX BODY?).Rodenstock and Schneider do not make cameras.Fuji
does.

 Fuji has had medium format cameras on the market for years.It wouldn't
surprise me to see the same Hasselblad sols in Japan under the Fuji name.

 The largest market for Hasselblad is Italy followed by Japan and the
U.S.A.I believe Hasselblad has seen the dramatic sales of Mamiya 645 and
Contax 645 and decided to up date their catalogue. A Hasselblad A16 back
sells in the U.S.A. for about $775.The Mamiya back is about $440.Without
leasing a camera,most people will opt for the less expensive
route.Hasselblad had to do something.

                             Robert B.
...


From sigma lenses mailing list:
Date: Sat, 28 Sep 2002 
From: "Peter Blaise Monahon peterblaise@yahoo.com" peterblaise@yahoo.com
Subject: Re: Minolta 600SI with Sigma 400/5.6


Hello Henk van Egmond,

OUCH - another sad Sigma auto focus lens incompatibility
story.

Tokina lenses are equally likely to not work on all
Minolta auto focus cameras, there are just fewer of them out
there.

Tamron seems to be the only lens manufacturer willing to
pay Minolta a royalty for the rights to use the original
Minolta programming in their lens chips.

Sigma and Tokina (in my experience) try to reverse
engineer their chips, and apparently fail miserably at being
truly compatible.  Sorry.  May I suggest the following label,
as now used by Cameta Camera NY in their advertising (at my
prodding - they also finally differentiate between Minolta SR,
MC and MD lenses at my prodding - it's worth talking to and
writing to people and suggesting, nicely, what would be a
better service offering!):

         
[For Minolta 5000/7000/9000 only]

Print this, cut it out and glue/tape it to the Sigma lens
barrel and at least stop anyone else from being trapped by
it's incompatibility.
         
Also, everyone, make sure there is a 100% buy back promise
when you purchase any Sigma or Tokina auto focus lenses
intended for Minolta.

         
How about Vivitar and Phoenix and Samyang and Cosina -
does anyone have any experience with these brands of lenses
working on older AND newer Minolta auto focus cameras?

         
Henk, on the Minolta 600si, you can use this lens as a
manual focus fixed aperture lens by telling the Minolta 600si
to go ahead and take pictures even though it does not 'sense'
a lens by doing the following:

Shutter Release Lock

Remove the lens first.

By sliding the Main Switch from LOCK to ON while
 pressing and holding the ISO Film Speed Button and
the Lens Release Button simultaneously, [On] or
[OFF] appears in Data Panel depending on the
previous setting.

 Pressing the ISO Film Speed Button will change
the display:

 [On] = Shutter can be released when film is
loaded and no lens is attached.

[OFF] = Shutter is locked when film is loaded
 and no lens is attached.

The Minolta 600si will then adjust only shutter speed
according to center weighted ot spot metering (your choice)
see
http://www.geocities.com/minolta507si600si650si/minolta507si600si650si-checklist08.html
and related pages for this information, and so much more about
your wonderful Minolta 600si camera.

         
You can also try writing to the other Sigma service
centers (see web page reference below) around the world to see
if another location still has the ability to service the
lens.  Since world wide communications and shipping is
available, why not use it?  It's a small world after all!

Good luck,
Peter Blaise
Minolta Photographer


from contax mailing list:
From: "Richard Wozniak" ric_woz@hotmail.com
Date: Sat, 05 Oct 2002 
Subject: [Contax] shutter lag time

Seems there are three components, logically, to lag time.~~

The first and longest is the time it takes an autofocus camera to
autofocus.~

The second is the amount of time it takes a camera to calculate
autoexposure.~ Note that if it is an autofocus camera the time spent
doing this can occur during the focusing operation and probably adds
nothing to the total lag time.

The third amount of time, which must take place after the two above is
the actual time between the shutter release trigger and the actual
shutter firing.~ This mostly has to do with the mechanics of the shutter,
trigger, etc.~~~ This last is very similar to a concept from guns called
"lock time" which is the time between trigger release and primer strike.

Logically this may be slower on a SLR than other camera types because the
mirror has to get out of the way.~~ On the RTS III the vacume

I recall that the "RTS" moniker of the original RTS I stands for Real
Time System and the claims were that the combination of 2 and 3 above
were extremely small, making it as fast in autoexposure mode as
traditional cameras were without AE.~

Here is some information on the Contax N1 from Pop. Foto.

http://www.popularphotography.com/Camera/ArticleDisplay.asp?ArticleID=9

here are the pertinent details:

Autofocus and time lag: Autofocus speeds (tested without AF assist light)
from EV 12 to EV 5 were clocked at approximately 2/3 to almost 3/4 sec,
an average-to-above average performance. From EV 4 to EV 1, AF time
measured nearly 3/4 to 1 sec, in the good to very good range. Results
were the same for high- and low-contrast test targets at all light levels
except EV1 where AF speed measured 2 sec, about average. The AF assist
light engages at EV 4 and lower light levels. Shutter lag time between
pressing the release and the shutter opening was a very short 1/10 sec.

Many sites also state the shutter (as opposed to autofocus) lag time in
milliseconds, or MS, which is 1000s of a second.~~ 100ms = 1/10th of a
second.~~~

Here is some other random stuff I found surfing on this topic.~

CrashDisc
PS:

here are some claims from photonet:

  Pentax 645n = 250ms (long)

  Rollei 6008--1/10 second. The report (Pop~Foto again) ~stated that
  this was the fastest they had tested for ANY slr. (They just tested
  the Contax 645, but I forgot to check that report before I left
  home.)

  For comparison:

  Nikon F100--140ms;

  Maxxum 9--1/6 second (=160ms)

  Rollei 6008i, after mirror lock-up: 2 (two!!!) ms.


From contax mailing list:
From: "Austin Franklin" darkroom@ix.netcom.com
Subject: RE: [Contax] shutter lag time
Date: Sat, 5 Oct 2002 

Richard,

> The second is the amount of time it takes a camera to calculate
> autoexposure.

It's important to be aware that it exists, but it is entirely deterministic,
and takes no appreciable time, as in, at the longest no more than 1ms but
more than not, far, far less.  Autofocus is the biggest killer...then
shutter/mirror/aperture deployment.

Regards,

Austin



From: "Jeffrey Frankel" jeffreyfrankel@mail.telepac.pt
Newsgroups: rec.photo.technique.people
Subject: Re: How to focus accurately with tele lens?
Date: Tue, 29 Oct 2002


I use a Canon so my experience may be different.  I found with autofocus on
200mm telephoto that I push the shutter button halfway to focus then if I
release it to move the camera position or talk to the subject, when I push
the shutter button again  the autofocus comes into action again, which means
it goes out of focus and then back into focus.  This process is a bit
disturbing.  So now I focus with AF, then switch to MF and then the subject
remains in focus (I may manually adjust).


Date: Mon, 20 Jan 2003 
Newsgroups: rec.photo.equipment.35mm
Subject: Autofocus Observations
From: Robin Burns r_f_burns@hotmail.com


I got my first autofocus camera recently (Maxxum/Dynax 9) and have noted
some interesting observations on its autofocus performance. First off, let
me say that I don't care too much about autofocus speed. I'm mainly a
landscape photographer, so speed isn't important to me, but accuracy is.

I tested by mounting an Air Force 1951 resolution chart on a wall and
photographing it with the camera mounted on a tripod. I lit the chart with
a 500w halogen spotlight (EV 10) to make sure the AF system had plenty of
light to work with.

With a 50mm 1.4 lens at its closest focus distance, I found that the
camera's AF system focused probably 99% as well as I could do focusing
manually. It was fairly repeatable too.

When I moved back to 15 feet, I started getting results that surprised me.
At f/1.4, most of my shots were not in focus. This is doubly surprising,
since at 15 feet the calculated DOF is 2.16 feet (14.0' to 16.2'). Why the
AF system couldn't focus to +/- 1 foot at 15 feet on a well-lighted, high
contrast target is beyond me. I tried various other targets, but saw no
difference in the results.

Switching to MF mode, I found that the focus confirmation LED in the finder
goes on well before critical focus is reached and stays on well past it.
This is also interesting and tells me that the AF system has plently of
slop.

Comparing AF to MF results, I found that the AF system consistently focuses
at the far end of its range, e.g. the point right before the focus
confirmation LED would go out when focusing manually and moving towards
infinity.

I also noticed that the lens distance markings are not calibrated too
accurately. When focusing on the target at a measured 15 feet from the
camera's focal plane indicator, the lens distance scale reads just slightly
closer than the 20' marking, and not exactly in between the 10' and 20'
markings as I would expect.

Anyone else have the same experience with AF? How and when do you use AF?
All of the time? Most of the time? Rarely?

- Robin


Date: Tue, 21 Jan 2003 
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Autofocus Observations
From: Robin Burns r_f_burns@hotmail.com


Mike Lipphardt wrote:

> No "seems" about it :)  Repeating patterns can and do confuse AF
> systems. Newer ones like the Maxxum 7's dual cross sensor are less
> subject to that problem (if one segment of the cross is confused, it
> chooses a different one), bit it still happens.

I used several other 'targets' and it didn't made any difference
whatsoever. In all cases, the zone of 'good focus' (as determined by the AF
system) was about 1.5 feet at a target distance of 15 feet and the AF
system *always* focuses at the far limit of that range. Unfortunately, at
large aperture (e.g. f/1.4), the focus point thus chosen is outside the DOF
limit and the image appears blurry.

Another interesting point: in all my tests, regardless of target or light
levels, I could *always* nail the focus better manually than the AF system
could (at f/1.4. At smaller apertures, it didn't matter as the AF system
could usually manage to focus within the DOF limits.)



From: rpn1@cornell.edu (Neuman - Ruether)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Autofocus Observations
Date: Fri, 24 Jan 2003

...
>Anyone else have the same experience with AF? How and when do you use AF?
>All of the time? Most of the time? Rarely?

Welcome to the wonderful world of AF (and AE...;-).
Manual still works better, and MF is still generally
faster and more accurate *if* your camera has sharp
VF optics (many do not), and *if* you can sharply see
at the VF screen effective focus distance (see
www.ferrario.com/ruether/articles.html#glasses for
a good glasses solution that can work for many for
both general seeing, and for 35mm camera focusing - wait
until the long page fully loads, and it will then "pop"
to the article...). A few years ago I developed a problem
with large, soft eye "floaters" which made me (kicking
and screaming) buy AF bodies and start acquiring those
icky, floppy plastic AF "lenses"... - but fortunately,
Nikon's first really good AF bodies had just appeared
(the F100 and F5). Previously, I had watched with
amusement as every new body from the 2020 forward was
introduced, and people announced that "finally, this
time Nikon has it right" only to find that none did
much better with AF than the lowly original 2020.
All could focus fairly well about 50% of the time,
missing slightly the rest of the time - and the
"electronic focus" was a bad joke, showing "correct
focus" over an amazingly wide range, with focus
"clearly" incorrect over most of the range... Now
I scale-focus (beyond 3' or so) the 20mm and shorter
lenses, and use AF with 24mm and longer lenses, and
this works well enough 95% of the time with the F100...
(BTW, AF accuracy depends on both the quality of the
camera design, and also the quality of the AF adjustment
on the particular body you use - testing for "centering"
of the AF within the DOF range is a useful thing to
do when buying an AF body...)


David Ruether
 rpn1@cornell.edu
 http://www.ferrario.com/ruether


From: Bill Jameson bjameson@mail.med.upenn.edu
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Autofocus Observations
Date: Fri, 24 Jan 2003


Robin Burns wrote:
...

> The point I'm trying to make is that autofocus systems are good, and
> getting better every year, but for applications where one can take the
> time, focusing manually still yields better results.

Thought I would repost this here, a discussion of the the 'precision
autofocus' on Canon's professional cameras. It does explain 'autofocus
slop' and the reasons for it:

______________________________

Date: Thu, 9 Aug 2001 
From: "Ken Lin" kenlin@idirect.com
Subject: EOS:  Re: centre cross sensor

The following was posted on the EOS3 user group, it was very good info that
I though to post this to the EOS group, the contributor is bigjohn813@netscape.net


As I go through the technical details of both, I noticed that EOS3's
central cross sensor AF point works only with f4 or larger. Why is    that?
What's the point of this? I clearly don't understand why is it    limited.
Is it supposed to be faster than other focusing points with    lenses with
aperture of f4 or larger ?
     No one really answered this initail question:  why do Canon's
professional AF SLRs use a cross-type AF sensor that requires use of a
fast lens to take advantage of both the horizontal and vertical cross-
type AF coverage provided?  To understand why, you have to understand  what
happens on the actual AF sensor iself during AF operation.
    All current AF SLRs focus by using at least one pair of light-
sensitive pixels, arranged in a straight line and separated from each
other (something like "--") on the actual AF sensor or "chip".  Cross-
type sensors use four such lines, two arranged 90-degrees perpendicular  to
the others.
    The camera's AF optics, located under the mirror in the base of the
camera body, split the incoming light into two separate beams for each
light pair using a very precise and tiny optical system.  The pair of
light beams is projected sharply on the line of pixels, and by  detecting
where on each line pair the light beams are focused, the AF  system can
detect whether the subject is in-focus, front-focused, or  back-focused,
and in either of the latter two cases send a signal to  drive the lens's AF
system in the proper direction.
    Here's where it starts to get interesting:  just as you have depth-
of-field at the subject itself, within the camera at the AF sensor you
have "depth-of-focus" -- a designed-in range of acceptable focus within
which the camera gives thumbs-up and declares the subject to be  properly
focused-upon, at which point the lens drive is stopped.  It's  a tolerance
designed into any AF system -- they all have it in one way  or another.
    It's a fact that the farther apart a pair of line sensors are, the
more exact and the less "wiggle room" there is in its decision as to
whether a subject is truly in-focus or not.  This is where the concept  of
"high-precision" AF comes in.  By using line sensors on their pro  SLRs
(starting with the first EOS-1) that are spaced further apart on  the
actual AF sensor, there is a significant increase in precision of  AF
evaluation and much smaller tolerance for the system to determine  what is
truly in-focus.
    This issue of precision is really a moot point when using a
moderate-aperture lens at normal focusing distances, like a 28-80 f/4-  5.6
zoom lens.  But it becomes relevant in terms of guaranteeing tack-  sharp
results when using fast professional lenses like the 400mm f/2.8,  200mm
f/1.8, 85mm f/1.2, or even wide-angle lenses like the 24mm f/1.4.  With the
closely-spaced line pairs of a consumer level camera like an  Elan or Rebel
(EOS 30 or 300), it's possible with these fast lenses and  their
tissue-thin depth-of-field to run into shots which are OK but  upon close
inspection are not tack-sharp, because of the range of  acceptable focus
settings that the closely-spaced line sensors have.
    The problem is this:  as the maximum aperture of the lens in use  gets
smaller (such as, from an f/2.8 lens to an f/5.6 lens), the  diameter of
the twin beams of light being projected onto the AF chip by  the AF
system's optics becomes smaller as well.  It has nothing to do  with either
the amount of light you're shooting in, nor the actual f/  stop you're
going to use -- it's only related to the lens's widest  maximum aperture.
    Thus, as you move the line pairs farther apart to increase their
accuracy and precision, you require a wider beam of light than some  lenses
can provide.  Knowing this, when an EOS-3, or any version of the  EOS-1
detects a lens is mounted with an aperture slower than f/2.8 (f/  4.0 at
the center-most point only for EOS-3 and 1v), it simply turns  off the
sensor pairs that are located far apart, knowing that such a  lens won't
fully cover all the pixels on the line pair(s) on the AF  chip.
    You can see this if you look at a picture of the AF sensor in the
brochures of a camera like the 1N, EOS-3 or 1v -- some sensor pairs on  the
chip are located far apart, while those arranged at a 90-degree  angle are
much closer together.  The latter guarantees operation with  the entire
range of lenses down to f/5.6 (f/8 at the center point only  with EOS-3 and
1v), while the sensors further apart provide much more  precise information
and focusing accuracy for those fast lenses that  need it -- IF you're
using one of those lenses.
    Cross-type sensors are a good thing, because in general you're  giving
the AF system twice as much information to work with to read the  subject's
detail and assess proper focus.  On their pro bodies like the  EOS-3 and
1-series, they've taken advantage of the cross-type design to  basically
give dual types of coverage, optimizing some of the  information for truly
professional lenses that can really benefit from  it.  With slower lenses
than f/2.8, all 45 AF points in the Area AF  provide the same level of
coverage (using vertical line sensors only,  closely-spaced so they're fine
with all lenses down to f/5.6), reacting  to horizontal and diagonal
detail, as mentioned in earlier posts.
    Bodies like the Elan and Rebel series, and the previous EOS A2/EOS-5
series, used a center point with cross-type coverage, but both  horizontal
and vertical pairs of line sensors on their AF chips were  closely spaced.
There was no high-precision AF claimed on these  cameras.  The benefit?
True cross-type coverage -- twice as much AF  information, very useful when
shooting subjects without much detail --  was available with any lens down
to f/5.6 (thus, pretty much any lens  in the system).  The problem?  For
those using very high-speed lenses,  if you were really critical, sometimes
there could possibly be little  frame-to-frame focusing inconsistencies,
even shooting a static subject  multiple times from the same camera
position.
    I know this is long and sort of involved, but it's necessary to  answer
the original question which is "why", and what are the benefits  of this
system as its currently constituted.  I hope this is helpful to  some of
you.



Date: Thu, 30 Jan 2003 
From: Robert Monaghan rmonagha@post.cis.smu.edu
To: D M ihate_ms@hotmail.com
Cc: Robert Monaghan rmonagha@post.cis.smu.edu
Subject: Re: AF vs MF.

thanks for your note and comments! see notes below bobm

D M wrote:

> Regarding the article here:
> http://medfmt.8k.com/third/af.html
>
> It is great that you can provide some numbers, but for those of us who do
> real world shooting rather than shoot LPMM and MTF charts, AF can be a life
> saver.
>
> There have been many instances when I was able to get shots of my highly
> mobile kids when I would have missed the shot with MF. And I've been an OM
> user for over 2 decades now, having cut my teeth on MF.

some AF users are missing these shots due to long delays in shutter release;
a zone focused lens set for lighting conditions would be faster, yes?

>
> You must realize that the end result of photography, at least for me, is
> getting a good image, not measuring LPMM / MTF. The great photographers like
> Henri Cartier Bresson used shooting techniques you would probably hate!
>
Bresson didn't use an AF camera, as Leica doesn't make an AF M series
leica ;-) There isn't much correlation between using AF or MF and getting
a great image, although it may be harder using AF for reasons I noted

> "AF is tripod "unfriendly" due to central AF sensor location(s) "
> When was that? 15-20 years ago? Almost all cameras today come with multiple
> AF sensors.
>
yes, and nearly all of them are still centrally located for reasons I noted,
they may not be dead center, but they aren't usually at the rule of thirds
points for example. there may be a few cameras with AF sensors outside the
central region, but vast majority of AF cameras are still center biased...


> "AF sensors are highly sensitive to orientation of vertical or horizontal
> edges in subjects (or lack thereof) "
> Can you manually focus on a blank wall?
>
sure, and when I focus on a fence, I don't get confused by the regular
black/white vertical zones, but some AF sensors may have problems with
orientation, again well documented in referenced articles...

> "Small aperture zoom lenses can readily poop out and starting "hunting" for
> focus lock in dim or low contrast lighting "
> Depends on what camera you use. If you are using some piece of crap like a
> Nikon N50 or EOS-5000 then good luck. In fact, manual focus with small
> aperture lenses is even worse. Half the split image circle will go black.
> Try focusing with that.

good point, but that's life for 95% of the AF camera users, since 95% of the
AF cameras sold are "pieces of crap"; as I repeatedly noted in the article,
if you want great AF, you can get it with very pricey pro lenses and fast
pro cameras at many kilobuck prices; but for vast majority of AF users, AF
is neither fast nor fun, and the slow zooms used make it even worse, yes?
> "AF is useless in macrophotography "
> Many times AF has saved my butt in macro photography. The 100/2.8 USM macro
> makes AF very useable. There are times when there has been no chance to set
> up a tripod, and I have had to take handheld shots with a flash and AF.
> Images have been excellent. I could simply not achieve that with MF.

handheld macro shots are a toss of the dice, regardless of what setup you
use; it is generally held by pros such as John Shaw (quoted on my page,
author of best selling Closeups in Nature) that AF is nearly useless in macro


> "AF is not very useful in ultrawide and very wide photography "
> MF is very difficult with wide lenses on an SLR. Unless you have superman's
> eyes. Better to have AF than struggle trying to focus a very wide lens.

generally, I don't struggle to focus a very wide lens, I just set the
distance scales conservatively based on the apertures in use (less one stop)
in my typical daylight or flash shots, that's accurate enough. However, if
you check the focusing with AF on ultrawides (and I have a 14mm AF on nikon
mount as experiece, still left from my trials of nikon AF kits), the focusing
done by AF is basically close but not exact either.

>
> "first generation image stabilized AF lenses are "tripod hostile" "
> Big deal. Turn off the IS when using a tripod. If you take the time to read
> the manual you would know this.

as the section at the bottom noted, this is a problem with the first
generation lenses, cited by users; the IS actually adds instability on
a tripod

>
> "Lack of DOF preview reduces utility of AF cameras for many users and owners
> of third party lenses etc. "
> Almost all Canon EOS bodies have a DOF preview feature, except for the
> bottom end cameras.

again, the same bottom end cameras that the vast majority of AF buyers
buy and are stuck using ;-) If people who champion AF had to use the crap
that the average user has been sold, i.e., the bottom of the lines, you
would not hear so much praise from many folks on AF cameras ;-)

>
> "Lack of mirror lockup adds vibration to many kinds of telephoto and other
> shots using many AF cameras "
> Almost all Canon bodies support some form of MLU or prefire.

and the ones which don't are the most popular and cheapest models which
have dropped this feature; but you are right, canon is better here than
say nikon or minolta; but for those wanting MLU, few cameras today have
true MLU or even prefire pseudo-MLU...
> "lack of depth of field and even distance scales on lenses makes use of
> hyperfocal techniques hard on many AF lenses "
> Most Canon zooms and primes have distance scales, except for the low end
> ones.

again, some high end lenses in some lines have full sets of scales, but
probably 90% of the AF lenses sold, i.e., the consumer models, don't. I
don't understand how much $$ they can be saving by not printing a scale?

>
> "AF cameras are often more complex, harder to learn, and may have hard to 
> use interfaces and controls " 
> Maybe a Nikon, but in the Canon system, most cameras have similar interfaces 
> and are very easy to learn. OTOH I have had nightmares with the Nikon N70. 


lots of us have had nightmares with the nikon interfaces (note plural ;-);
A few AF cameras have full controls (see pentax series) and are very easy
to learn, but most have 50+ page instruction manuals (some over 200 pages)

I can generally work out use of features on any manual 35mm SLR,
rangefinder, TLR, Med Fmt SLR and view camera in a few minutes. The same
is not true of most AF and some electronic cameras with LCD interfaces;
you need a key to figure out what the Icons mean on many models...


> "AF cameras may read ASA directly and provide limited overrides, producing
> problems when trying to shoot at night (e.g., reciprocity) "
> Have you heard of manual ISO setting? Even the bottom end canon cameras
> allow that. And there is something called exposure compensation on almost
> all cameras. And Bulb exposures. And cable releases. This point is totally
> invalid.
well, it is valid for lots of AF cameras whose only override is a
backlight button (e.g., many 35mm SLR models at lower end, and point and
shoots AF models - also covered under AF cameras after all). There are lots
of AF cameras (and some manual ones too) that don't have ISO manual
adjustments, or bulb exposure options. At best, you get a backlight button
one adjustment, and only two stops.  Again, I said there are AF models
that "may" not provide overrides. Statistically, circa 80% of all AF
cameras sold are point & shoots that probably fall in this category...

> "AF cameras with on-camera flash is a recipe for "red-eye"
> Big deal. Get a cheap shoe mounted TTL flash, just as with the older MF
> SLRs. The on camera flash is just there for convenience, in case you are
> caught without a flash.

is that why so many red-eye pens are sold at minilab print counters? In
some cases, it is hard to defeat the mini-flash without pressing a lot of
buttons and missing a shot. Some small cameras don't have a flash shoe,
i.e., the low cost ones sold most often to consumers wanting "AF" ;-)

>
> F cameras coming with short range "normal" zooms (35-70mm) can't replace the
> normal 50mm lens - the fastest, sharpest, and lightest lens most of us own
> and use "
> Big deal, again. The normal 50/1.8 costs around $65. So get it already. In
> fact, except for the bottom end SLRs you can choose not to get a kit zoom,
> and get the 50mm instead.

sure, but very few 50mm lenses are now being sold, as I noted, and most kits
feature the zooms, and that's what folks buy. On some cameras, the zooms
are fixed, that's what you get. ;-)

do you know that the average number of lenses sold per SLR body sold is 2.4?
few folks are going to buy a 50mm lens if they already "cover" that with
their zoom, as shown by lower sales nowadays of normal 50mm lenses.
> "If autofocus were really all that great, then why aren't all the pros using
> it (e.g., on medium and large format)? What do the pros know that you don't?
> "
> Almost all MF manufacturers offer AF today. Contax, Mamiya, Hasselblad,
> Pentax and Rollei included. I know many pros who use AF medium format
> systems for portrait shooting. That said, the style of working with medium
> format is quite different from 35mm AF systems, so you might not really need
> MF. And if you want AF on large format cameras, I wish you all the best.

AF sales on med fmt remain in the 10-15% of sales range; so again, not a big
market segment. Most of these buyers are probably 35mm users "upgrading"
to med fmt who demand these features, not realizing as you correctly note
that med fmt and 35mm are different, and in med fmt quality is the key issue,
while in 35mm I think convenience and economy are more of an issue IMHO...
> At the end of the day, it is getting the image that counts for me, not
> measuring LPMM and numbers. Modern AF systems work extremely well and allows
> me to capture the images I like. I agree that with careful manual focusing
> you might get better resolution but in most cases it really doesn't matter.
> When I shoot sports, it's capturing the moment that matters. Same with
> parties. With portraits, I know exactly what workflow to use, and AF helps
> me get the right shot - a lot easier than MF. (I still use manual focus on
> medium format for portraits though, but that is with older people who can
> stay still, not small kids / babies).

As I have noted, there are areas like sports where AF can work well, esp.
with good pro cameras and fast lenses. I think we both agree that the
"piece of crap" low end AF bodies, which are what most folks buy, don't
work well here either, esp. not with slow zoom lenses. For most AF users
and buyers, the experience fails to deliver the many promises, while
limiting many areas of photography (I have a long list at af.html end).

> So in short, it doesn't matter if you can get 50 or 60lpmm, it is capturing
> the image that matters.

yes, agreed, but many times AF causes problems for the average AF user; the
pros know this, which is why they buy the high end bodies and faster glass.
Right? I mean, I routinely use an old SRT101 or pentax spotmatic or nikkormat
with manual lenses and get the same quality of results as I would with
the top of the line models (F2..). I don't think that is the case with
the low end "piece of crap" (quoting you ;-) AF bodies and slow lenses today.

the other point is that many folks are paying major $$ for high end pro
quality faster lenses, but the AF limitations are not delivering the full
100 lpmm the lenses are capable of delivering. That was my experience
with nikon AF, and why I have kept my 14mm AF and 35mm f/2 AF etc. lenses
but got rid of the clunker AF bodies. The lenses work great on a manual
focus body, with care on a tripod you can get the benefits you paid for.
but with the same lenses on a AF body, you can't, you are lucky to get
40 or 50 lpmm (and in some cases, get a lot less, as test scores noted).

Paying big $$ for pro OEM AF lenses (because they are compatible, but
the third party lenses aren't available or may be problematic), and then
finding you are only getting a modest level of performance due to the
limitations of AF design and operation of sensors, is a problem in my book.

This is one reason I moved on to medium format; I couldn't get more quality
for more $$ on newer AF cameras in 35mm, but small $$ invested in medium
format yielded big quality and enlargeability gains.

If you are doing modest enlargements, the failure to get more than 40 or
50 lpmm resolution is okay, up to about 8x10" or even 11x14" viewed at a
greater distance. But if you want the best quality that 35mm can deliver,
the average AF system can't deliver it even today, while many manual
focus systems can do so with careful technique.

but you are right, most folks don't do enlargements beyond 5x7" so they
are happy with even crappy AF results ;-)

grins bobm



Date: Fri, 24 Jan 2003
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Autofocus Observations
From: Robin Burns r_f_burns@hotmail.com


 wrote:

> Just got a new Canon for Christmas. This is my first camera with
> Autofocus. Since Christmas have had 4 films done. I have only had
> three pictures that were out of focus. Those were because I was
> getting a feel for the focus and accidentaly tripped the shutter. Just
> got back my last set yesterday afternoon and both myself and the wife
> continue to remark how sharp the pictures are. In fact my first two
> rolls were of the Christmas family gathering and some of the pictures
> were so sharp that on facial closeups they were in some cases
> unflatttering. I dont know if this camera is fast or not, it certainly
> seems fast enough to me. I do notice that on some objects it seems to
> take a little more time. I do know that it is much faster than my
> grandson. So far I have done some portrait, landscape and closeup of
> flowers and I was very satisfied with all of them. I am using the DOF
> setting more and more and getting better results all the time. I'm
> very satisfied with the quality and the speed that I am getting.

But have you performed a critical test of AF? It sounds like you just took
a couple of snapshots and were satisfied with the results. Try a worst-case
situation (maximum aperture, minimum focusing distance) with a target where
you can really see small focusing errors and see if you still feel the
focusing is adequate.

Here's a simple test I'm sure you'll find enlightening: put the camera on a
tripod, switch to manual focus, and focus on a high contrast object while
watching the in-focus indicator. You'll probably find it comes on well
before you reach true focus and goes out well after you pass focus. When
you're focusing on something 1.5 feet away at f/1.4, the depth of field is
less than 1/4", but the autofocus 'slop' is considerably larger.

There is a wide spectrum of what people find acceptable. I've seen people
who have no problems with fuzzy prints that have large color shifts. Others
will accept nothing less than perfect focus and color. Yet others make
16x20 prints from a 35mm negative and pronouce them 'grainless' whereas I
see the grain in 4x6 prints from the same negative.

The point I'm trying to make is that autofocus systems are good, and
getting better every year, but for applications where one can take the
time, focusing manually still yields better results.



From: rpn1@cornell.edu (Neuman - Ruether)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Autofocus Observations
Date: Sat, 25 Jan 2003

...

I've never found these AF indicators very accurate - they
show "OK" when the focus is far from correct... BTW, if
the eye problem is one of age-related inability to focus
over a wide range of distances, there is a very good
glasses solution that works well for optimizing both
camera VF seeing, and also general seeing - this has
worked well for me for many years. It is described at:
www.ferrario.com/ruether/articles.html#glasses (let the
page fully load, and it will snap to the correct article).

David Ruether
 rpn1@cornell.edu
 http://www.ferrario.com/ruether


Newsgroups: rec.photo.technique.nature
Subject: Help with AF
From: "Joe A." jogging_to@hotmail.com
Date: Wed, 26 Feb 2003

I recently bought an Auto Focus SLR, something I didn't have before. It's
taking time to adjust. I enjoy nature photography, particular birds.

Over the weekend I visted an large arboreum to practice with the camera.
Shooting birds on the feeder was a snap. The AF homed in quickly and the
focus turned out to be perfect.

However, when I tried to shoot birds in low shrubbery it, (AF), didn't work
very well. It kept re-adjusting, first at the shrubbery and then at the
bird -- back and forth without settling down on the bird. I tried spot
center-weighted and matrix without any success. My brand of camera (Nikon)
does not snap the shutter unless focus has been achieved. 

Am I doing something wrong?

Joe 


From Manual SLR mailing list:
Date: Tue, 7 Jan 2003 
From: Dante Stella dante@umich.edu
Subject: Messraster

Does anyone have a picture (drawing) of a Messraster from a
Reflex-Korelle?  This is a funky focusing screen with the groundglass
in stripes on both sides of the glass.

Thanks
Dante


From: Bill Tuthill ca_creekin@yahoo.com
Newsgroups: rec.photo.equipment.35mm
Subject: Chasseur d'Images & slow AF on digicams
Date: Thu, 23 Jan 2003


I won't repost them here, but the latest test by Chasseur d'Images
of digital camera autofocus merits discussion.  Here are my notes:

 http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=004PM5

The test writeup is available in French at the following URLs:

 http://www.photim.net/Acrobat/CI-250-Speed-Intro.pdf
 http://www.photim.net/Acrobat/CI-250-Speed-Mouv.pdf
 http://www.photim.net/Acrobat/CI-250-Speed-Late.pdf



Date: Fri, 24 Jan 2003 
From: Robert Monaghan rmonagha@post.cis.smu.edu
To: Robert Monaghan rmonagha@post.cis.smu.edu
Subject: af speeds etc great quote on AF D60 << F100

I hope Chasseur d'Images follow this report with one on film based SLRs.
My personal experience is that my D60 focuses much slower than the F100 I
had previously. The autofocus on the D60 is nearly useless in daylight
and completely useless in low light. The F100 focused quickly and
accurately even when shooting high school football games played at night
(ISO 2500, F2.8, 1/250 sec).

-- Chris Hawkins (USA, Ohio) , January 22, 2003

from http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=004PM5


From: Le Grande Raoul raoul@olympus.net
Newsgroups: rec.photo.equipment.large-format
Subject: Re: How to shot LF handheld?
Date: Tue, 04 Mar 2003 

Marv Soloff
 wrote:

> Classic LF 4 x 5 handheld was all the shots by Weegee. No nonsense - he
> just picked up the camera, loaded it with film and shot. Became very famous.

Somewhere on www.graflex.org, there is a description of WeeGee's
techneque (I think it is in the FAQ).

He had two focussing marks on the bed- near and far. He used those
bigassed flashbulbs and usually shot at f-11 or f-16. (I think if he
was shooting at the "far" position, he used f 11, f-16 if shooting at
the near setting.)

I beleive he was more of a 'decisive moment' photographer rather than a
'technically perfect' photographer. It's amazing how worried we are
about technical perfection- in focus, perfect exposure and, in fiddling
with the controls, we miss the moment.

On a related matter, in talking with a working news photog friend, I am
reevaluating the use of zoom lenses. He was shooting basketball and
was using fixed focal length lenses. He was using a Nikon D1X
(according to him, the news photog's friend) and a 60 mm and an 80mm.
Due to the size of the sensor in the digital camera, this equates to an
80 and 135 with a silver 35mm. I asked, "Why no zoom?" He said, "Can't
think that fast. I find it's better to take fiddling with the zoom out
of the equasion and just concentrate on the shot." He does really good
stuff. Been working for three daily and weeklies for about twenty
years.

Jeff


From: "Roger N. Clark" rnclark@qwest.net
Newsgroups: rec.photo.technique.nature
Subject: Re: Autofocus with fast action photography
Date: Sun, 20 Apr 2003 

Scott Elliot wrote:

> Roger, if the subjects are accelerating or moving how is one shot auto focus
> going to be any better than AI servo?

Scott:

I have sequences of birds taking off and landing, and of dogs
running toward me where the first frame is in focus but
each subsequent frame is more and more out of focus.
The AI seems to get progressively off (I've observed this
within the last 6 months on 3 Canon cameras: Elan 7e,
D60, 10D).

However, with one shot mode, the focus system locks on to the
subject and fires. The focus error is as good as the
first image in AI mode, and better with each subsequent
frame. Note that in multi-frame mode (where you hold the
shutter down and the camera frames away), each subsequent
frame is more and more out of focus. So for rapidly moving
subjects, the best solution seems to be to raise your
finger off the shutter button between frames so that each
image has a new focus when you press down on the shutter.

The AI systems lag too much. Here is a simple test:
Standing, point your camera straight down and focus
on the ground. Have the camera in AI mode. Now pan
upward with your finger on the shutter, pressing
half way to engage the focus system. Listen to the
camera's autofocus. You'll hear it move in little
jumps even though you move at a smooth angle.

Because the ground distance is moving away as the tangent
of the angle from straight down, it is effectively
accelerating, and the system can't handle it.


The focus error builds up, and if you are shooting, you
get poorly focused images.

Roger


From: "Ken Wyatt" ken@wyattphoto.com
Newsgroups: rec.photo.technique.nature
Subject: Re: Autofocus with fast action photography
Date: Sat, 19 Apr 2003 
Hi Roger,

Michael Reichmann recently addressed this in hi mini-review of the 10D.
Here's the link: http://www.luminous-landscape.com/reviews/cameras/10d.shtml

The D60 was never known for it's fast focusing...

Regards, Ken
...


From: "Roger N. Clark" rnclark@qwest.net
Newsgroups: rec.photo.technique.nature
Subject: Re: Autofocus with fast action photography
Date: Sat, 19 Apr 2003 
...
Ken:
My post was meant to be more general than just D60/10D discussion.
It is well known that the 10D is faster than the D60. I have a
fair amount of in the field experience now with both D60, 10D, and
with film cameras (all canon in the last 10 years). While
the 10D has a snappy response and is quite similar in response
to my elan 7e film cameras, all fail about equally in achieving
critically sharp focus. Having spent the morning reviewing
my 1800 shots in detail from this week's Florida trip, I find I
have about 288 nice compositions plus good focus, a 16% ratio.

But many are not in critical focus, in fact far less than I
originally thought. While I gained a higher percentage of
close, I don't think the percentage of critically sharp
ones are any better than with the D60. The main reason
appears to be focus error on accelerating subjects.

I think I will never use AI servo or AI focus again, but always
stay in one shot.

Roger


From: "Roger N. Clark" rnclark@qwest.net
Newsgroups: rec.photo.technique.nature
Subject: Re: Autofocus with fast action photography
Date: Fri, 18 Apr 2003 

This website shows plots of bird velocities.

http://www.biology.eku.edu/RITCHISO/554notes3.html

It shows speeds in the 7 to 16 m/sec
which equals 33 to 76 miles/hour.
This indicates my previus numbers regarding focus and
smear are 3 to 8 times too low.

Roger


From: "Roger N. Clark" rnclark@qwest.net
Newsgroups: rec.photo.technique.nature
Subject: Re: Autofocus with fast action photography
Date: Fri, 18 Apr 2003 

Scott Wuerch wrote:

> I use AV mode and set my aperture at f8 or higher so that my
> depth-of-field will cover some focusing boo-boos. As you know the wider
> the aperture the narrower the DOF. I am using either a EOS Elan7e or a
> 620 with "L"-series optics also.

In my first experiments with action photography, I thought I
had depth of field problems causing the focus error. However,
I found that unless exposure the time was at least 1/2000 second,
(preferably 1/4000) closing the aperture just made motion
blur worse and made overall image sharpness decrease.
I found I must keep the aperture wide open unless I hit the
upper shutter speed limit of the camera. All this is regarding
bird flight photography and dogs at play.

With bird photography with a 500 mm lens and 1.4x TC and either
sharp film or the Canon D60/10D digitals, the film resolution
is on the order of 3 arc-seconds. A bird moving at
10 miles per hour at a distance of 50 feet traverses a
3-arc-second angle in only 1/20,000 second (if I did the
calculation right). You must expose faster than that
to not see smear (probably at least half, perhaps 1/3).
Thus you need very fast exposure times. You can compensate
by tracking.

Now if the bird is moving toward or away
from you at 10 mph = 14.7 feet/sec, the focal point is
changing 15.8 mm/sec or 12 microns in 1/1000 sec.
At f/4, a point source 12 microns from optimum focus
would be 3 microns in diameter (using geometric optics),
and at f/8 1.5 microns.

A search on the web for bird flight velocities, I found geese
migrate at 19 meters/sec ~ 90 miles/hour. Then consider birds
much closer than 50 feet (ideally filling the frame). This could
increase the speed requirements many more times. Thus, the above
numbers can be low by more than 10 times, again pointing to
the need for very fast shutter speeds to attain sharp focus.

Roger Clark


From: PWW Nomail@nomailplace.com
Newsgroups: rec.photo.technique.nature
Subject: Re: Autofocus with fast action photography
Date: Fri, 18 Apr 2003 

Roger,

I shoot with Nikons, but some thoughts, which might apply and might not.
With Nikons there is a big differences with different lenses. An
example; the 80-400 VR Nikon (VR Vibration Reduction) lens has had a lot
of people saying that it is very slow to focus and loses focus track
relatively easily. But the new 70-200 Nikon VR lens has super quick
focus and tracks very well, at least in the bird shots I shoot. So it is
not all the camera's responsibility. I even think that it is the lens
which is more important for that type of focusing.

I personally never did like just pressing the shutter button and letting
the camera buzz through the action. I did try that technique in the
beginning but it seemed the shots that were recorded were never the ones
I wanted. So I went with the technique that when I press the shutter
button it takes a photograph. I also don't us the focus lock technique
It seemed limiting to me in the wildlife arena.

In the end a don't think there is a perfect system, yet. But sure is a
lot better than the old days, when we were trying to get those flight
shots with a non-focus lens. Ohhh man, I used to fill trash cans with
slides that did not make it.

PWW

"Roger N. Clark" rnclark@qwest.net wrote:

> Hi
> I've been doing bird in flight photography and have some issues
> with autofocus during fast action.
> For successful examples, see:
> http://www.clarkvision.com/galleries/gallery.bird
>
> Most of the above images were with a Canon D60, but I just
> got back from Florida where I tested a Canon 10D with about
> 1800 images (very successful trip with lots of bird action).
> I've also used canon film cameras up to Elan 7e.
> All cameras behaved similarly (except the D60 was the poorest
> response of the bunch; the 10D best).
>
> There are generally 3 autofocus modes on the Canon cameras I've
> used (10D nomenclature below):
>
> 1) One Shot: camera will not fire unless focus is locked,
> and you can do one frame. Each frame must achieve focus lock.
>
> 2) AI Focus: same as one shot, but if the camera detects movement,
> it changes to AO Servo (#3 below). It apparently must achieve
> the focus lock before the first frame fires.
>
> 3) AI Servo: camera continually tracks focus and fires whenever
> you press the shutter.
>
> Add to the above modes are the drive:
> A) 1 frame or
> B) multiple frames.
> In one frame, you must push the shutter for each image, with
> multiple frames, you can hold down the shutter and multiple
> frames are taken.
>
> QUESTION: Which modes give the sharpest images on fast
> moving / accelerating subjects?
>
> I have done a lot of testing of both film and digital cameras
> on rapidly moving subjects: birds in flight, and dogs at play.
> Both subjects often have fast movement that can change direction
> rapidly. Further, there is rapid acceleration or deceleration.
>
> My experience is that the canon autofocus tracking may work
> for constant velocity but fails with acceleration.
> I have gotten the most consistent (see above) sharp images
> in single shot mode (#1) with either drive mode (A or B).
> However, in mode B, if the subject is accelerating (like a bird
> taking off or landing) subsequent frames are in poor focus.
> The focus system tracks, but just not well enough. At least not
> enough for even sharp 8x10 prints. (If you would like, I can
> post examples of sharp versus not sharp.) Of course, if the
> subject is moving mostly across the field of view, and changing
> distance little (like side view of a bird taking off), the
> autofocus system works very well. But with face on shots of a
> bird taking off, it is accelerating, so autofocus fails.
> In these situations, fast exposure is critical too. I use
> use L lenses (e.g. 500mm f/4 IS) at 1/2000 sec and faster.
>
> So, have others experienced these issues? If so, how do you
> deal with it?
>
> Roger Clark


From minolta mailing list:
Date: Mon, 28 Apr 2003 
From: "Magnus Wedberg" mw@9000.org
Subject: Re: Continuous Autofocus...

> For those of you who shoot sports, or other moving subjects often, can
> you really tell much of a difference when using Continuous AF, rather
> than Automatic AF? Are you able to get shots you wouldn't have gotten
> otherwise? 

I can't say that I shoot it "often", but sometimes I do (mostly birds
in flight and skiing) and then continuous AF is very good to have --
because it will never try to achieve "lock". Automatic AF works fine
most of the time even for moving stuff, but when a subject (a bird
changing direction for example) "stands still" for too long, the
camera will lock, but then the subject moves on... and you have to
start over again.

--
Magnus Wedberg
http://mw.9000.org/


From: "Scott Elliot" selliot@telus.net
Newsgroups: rec.photo.equipment.35mm
Subject: Re: I bought a Stigma...
Date: Sun, 27 Apr 2003

Skip, ask the Tokina rep where he got that information. Also get him to
explain why so many Tokina lenses had to be rechipped when the EOS 3 was
introduced.

Scott Elliot
http://www3.telus.net/selliot/

"Skip Middleton" shadowcatcher@cox.net wrote
> I had it from a Tokina rep that they licensed the mount, but I can't speak
> about the Tamron.
> --
> Skip Middleton


From: DFM mcindan@hotmail.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Cheapish 400 5.6 AF lens...
Date: Thu, 17 Jul 2003 

"Tim O'Connor" tbo@spamsucks.bigpond.net.au wrote:
>Can anyone recomend a decent 400 5.6 in the Nikon AF mount? Ive seen Sigma
>400 5.6 floating about the second hand markets, and it seems to be
>a reasonable performer, by all accounts.

I found AF to be of limited use for both long lenses and macro work back in my
Canon EOS 620 days. I now have a D100 (and F70) and have a Micro Nikkor 200/F4
and Nikkor 400/5.6 ED, both MF lenses. I had them "chipped" by Rolland Elliot
and they meter just fine in all modes.

..Dan


From: Mxsmanic mxsmanic@hotmail.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Auto focus accuracy
Date: Wed, 16 Jul 2003 

Al Denelsbeck writes:
> Try http://electronics.howstuffworks.com/autofocus.htm.

That page is in error. It implies that good SLRs use contrast-based
passive autofocus, but that it not true.

Good SLRs use rangefinder autofocus. The AF examines image detail using
rays from opposite sides of the lens. If the image is in focus, these
rays will converge on the AF target. If the image is not in focus, they
will be separate by a distance that is related to the focus adjustment
required to bring them into focus, and the direction in which they are
separated will indicate the direction that the focus must be adjusted.

You know you have a rangefinder autofocus system if your camera's AF
won't work with lenses that have a maximum aperture smaller than a
certain size (usually f/5.6). This is because the AF must see rays
coming through opposite sides of the glass, and this isn't possible if
the aperture is too small. Contrast-based systems don't care about
aperture and will work with any lens.
--
Transpose hotmail and mxsmanic in my e-mail address to reach me directly


Newsgroups: rec.photo.equipment.35mm
Subject: Re: Auto focus accuracy
From: Al Denelsbeck news@wadingin.net
Date: Wed, 16 Jul 2003 

...
> Can someone direct me to an explanation for how auto-focusing actually
> works? Where are the focus sensors located in the camera?

Try http://electronics.howstuffworks.com/autofocus.htm.

The location varies, but typically, there is a partially-nonsilvered
'semi-pass' portion of the SLR mirror, with another mirror behind it
oriented differently. This allows part of the image to pass through the
main mirror and be bounced downward to the AF sensor, which is often
coupled with the light sensor for metering. So the AF sensor is often
sitting flat on the bottom of the camera interior.

I seem to recall some models having the AF sensor located just behind
some surface of the pentaprism in the top of the camera, but not entirely
sure of this. I do know some models put their exposure sensors there.

- Al.


From: "Phil M" kamwm@netcomuk.co.uk
To: "Nikon Group" nikon@photo.cis.to
Date: Tue, 18 Nov 2003 
Subject: [Nikon] Are AF lenses durable and reliable?

I used to be very reticent to put lots of money into AF lenses. I bought a new
AF 35mm f2 which was so 'loose' that at times the whole optic-barrel would
displace during focussing and then view-finder image jump. I took it back.

I instead got a s/h 35mm f1.4 AI, which even has adjusters to make sure that
the optic barrel is snug even if the metal runners wear through massive use.
(AIS lenses don't seem to have these adjusters.) I know that AF requires a
lighter focussing action, and I have an AF 50mm f1.8, but I'm sceptical about
the 'plastic' loose threads on AF lenses. Are they 'suspended' in the
lubricant? It seems they need 'servicing' if the lubricant fails because they
then become floppy. (Canon EOS does too.)

(I also got a new 50mm f1.4 AIS and 105mm f2.5 AIS because of my doubts about
AF.)

I guess I'm wrong somewhere. Why do Leica manufacture their metal lens
components to such narrow tolerances if it doesn't really matter?

Puzzled,

Phil


From: Alan Browne alan.browne@videotron.canospam 
Newsgroups: rec.photo.equipment.35mm 
Subject: Re: shutter lag time (AKA time parallax) 
Date: Thu, 11 Sep 2003

Dave Bouvier wrote: 
> Check out the Nikon D2H previewed at 
> http://www.dpreview.com/articles/nikond2h/. It uses a mechanical shutter 
> that has a 38ms shutter lag. Significantly faster than the 50-70ms for the 
> R8/9. 
> 
> Dave 
IMPRESSIVE! Not the 37ms, but the 80ms total mirror blackout: 
"37 ms shutter lag, 80 ms viewfinder blackout - Nikon has concentrated 
on reducing shutter lag (the lag between the moment you fully depress 
the shutter release and the time the shutter curtain opens), the D2H's 
quoted 37 ms shutter lag is the fastest of any digital SLR. The 80 ms 
viewfinder blackout is something you have to see to believe. Depress the 
shutter release and its literally no more than the blink of your eye 
before the image returns to the focusing screen. The viewfinder also has 
a full 100% frame coverage." -- www.dpreview.com 


Newsgroups: rec.photo.equipment.35mm 
Subject: Re: shutter lag time (AKA time parallax) 
From: Magnus W vader@death-star.spam-trap.com
Date: Sun, 14 Sep 2003 

"David J. Littleboy" davidjl@gol.com wrote 
> "Alan Browne" alan.browne@videotron.canospam wrote: 
>> David J. Littleboy wrote: 
>> > 
>> > That's nothing. There are digital cameras with _negative_ shutter lag.  They 
>> > continuously record images and save the last one it recorded _before_  you 
>> > hit the button. 
>> Really? Which ones? 
> 
> Well, only one. An old 1MP Olympus had this feature at one point. 
The new Minolta Z1 has a similar feature -- it records images as long as 
the shutter release button is depressed, discarding the oldest all the 
time. When the button is released, it saves the seven (or so) latest 
pictures. This is the future of photography, and I think it's kind of sad. 
I didn't know of the Olympus though. 


From: Alan Browne alan.browne@videotron.canospam 
Newsgroups: rec.photo.equipment.35mm 
Subject: Re: shutter lag time (AKA time parallax) 
Date: Thu, 11 Sep 2003 

Peter Chant wrote: 
> Hmm, if anyone has said camera and a high speed videoi* (unlikely) it 
> ought to be relatively easy to measure. 
Put an accelerometer on the frame of the camera, bring the lead to port 
A of a digitizing O'scope. May need some analysis to figure the best 
point to place the accelerometer. 
Put a photo resistor in series with another resistor with 2 V across the 
two; measure the voltage accross the photo resistor with port B of the 
O'scope. 
Pre-trigger on B. 
The photoresistor should be placed in back of the shutter and then the 
whole are covered to reduce or eliminate light getting at it. This 
channel will detect the change in light when the shutter begins to open. 
Examination of the accelerometer channel should see the shutter release 
depression, a sharp mirror movment and the beginning of the shutter 
opening. The light channel will show the first light coming in the 
shutter. If the Leicaflex has a shutter release, this would be reccomended. 
Worth a try for anyone with a Leicaflax handy and a friend with the 
oscilliscope and variious doo-dads. The accelerometer can be borrowed 
from someone who works at a company that has a vibration lab. 
The Leicaflex is slow enough that Heisenberg's uncertainty principle 
will not result in significant error in the measurements. 

Cheers, 
Alan


From: gsm@mendelson.com (Geoffrey S. Mendelson)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Identifying AF or AI-S Nikkors ...
Date: Mon, 12 Jan 2004

William Graham wrote:
> In some cases, their non-AF lenses are more expensive than the AF lens of
> the same speed/focal length.....I would give an example, but I don't have my
> magazine ads with me right now........

That's on purpose. The manual focus lenses are made using a very expensive
helicoid (spiral) ring. The AF lenses use "rack and pinion" gears to focus
which are much cheaper to make.

Geoff.


From: "Jeremy" jeremy@nospam.thanks.com
Newsgroups: rec.photo.equipment.35mm
Subject: Carl Zeiss On Autofocus . . .
Date: Mon, 12 Jan 2004

> > So what the **** is the point of autofocus????
>
> Good question!!! ;-)
> If it were not for the loss of sharp vision in the center
> of my "camera" eye, I would not ever use it - a good
> matte viewing screen in a camera with good VF optics
> is both easier and faster to use than AF most of the time,
> and, I think, generally more accurate

Interesting bit of text in one of the Carl Zeiss lens datasheets--the one
for the Apo Makro-Planar T* 4/120 lens in the Contax 645 camera system. I
believe that all of the lenses for that system, with the exception of this
one, are autofocus designs. Look at what Zeiss says about this macro lens:

"The Apo Makro-Planar T* 4/120 lens is targeted at the meticulous close-up
photographer who is in full control of the technical aspects of the picture
taking situation, AND WHO EXPECTS UNCOMPROMISING IMAGE QUALITY AS REWARD FOR
HIS EFFORTS. He is used to do very careful and well thought placement of
the focus himself , AND HE WOULD NOT USE THE AUTOFOCUS ON HIS IMAGING
PROJECTS. CONSIDERING THIS NEED FROM PROFESSIONAL PHOTOGRAPHERS AND KEEN
AMATEURS ALIKE, THE APO MAKRO-PLANAR T* 4/120 LENS IS EQUIPPED WITH A HIGH
QUALITY PRECISION MECHANISM FOR SMOOTH FOCUSING AND NO AUTOFOCUS."

It certainly appears to me that Zeiss is making a statement about the merits
of manual focusing over autofocus. Like, maybe. good ole' manual focus
still has an edge over the newer, and more expensive, autofocus?



From: rmonagha@engr.smu.edu (Bob Monaghan)
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Nikon AI vs. Super Takumars
Date: 3 Nov 2003 

the key investment for most of us is in the optics for various 35mm and MF
systems. A digital camera body which could mount optics from various 35mm
camera systems and a larger sensor version for MF would be a nifty way to
add digital, especially if you could use different lens brands on the same
body (as with T4/TX automatic diaphragm mounts). This could probably work
with AF simply by moving the chip back/forward, as with the Contax SLR
design, thereby turning all manual focus lenses into AF operation on the
new digital body ;-) this would also simplify the problems mechanically to
a simple lens mounting system for most brands, expanding the range of what
one digital design box could do. Think of it as a third party body for
multiple makers lenses? ;=-)

grins bobm


From: stacey fotocord@yahoo.com
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: What was wrong with film?
Date: Sat, 17 Jan 2004 

steven.sawyer@banet.net wrote:
> Actually APS hurt all of them a lot. It was a brilliant idea, but the film
> size was ill conceived. 

Exactly. They were STUPID to make the film size smaller than 35mm. The 35mm
P&S;'s (Think olympus stylus) are about as small as a camera can get and
still be able to hold it. If they had made it like 35mm size without the
sprocket holes, given a larger negative than 35mm, they would have insured
film's life over digital for a longer time and actually given people
something for the upgrade. Greed got in their way.
--
Stacey


From: "David Ruether" rpn1@no-junk.cornell.edu
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Carl Zeiss On Autofocus . . .
Date: Wed, 14 Jan 2004 

"William Graham" weg9@comcast.net wrote
> "Jim Waggener" jimw@visi.net wrote 
> > " These days I think manual focus is better for things like portraiture,
> > macro, landscapes, and suchlike."

> > Pretty wide range of use, don't you think?

> With me, it depends on time and light....If I have enough of both, then I
> can do a decent job of manually focusing my lenses. If I were a sports
> photographer, then I think that I would have to go with AF because of the
> time restrictions. And now, with my failing vision, there are lighting
> situations where it is very hard for me to manually focus, and I have to
> depend on the little green LED in my rangefinder to tell me when I am in
> focus......

I tend to believe that given good camera VF optics (this is MUCH
rarer now than it used to be, with only a few cameras having really
sharp SLR VF images), with good eye-correction for the VF apparent
focus distance (generally around 1 meter) and astigmatism (if any),
using a lens that is an optimum speed (f2-2.8 for MF cameras and
the better AF cameras) and of good optical quality (not soft
wide-open) for good MF, and a bit of MF experience, most people
would find MF preferable to AF most of the time, regardless of age.
Unfortunately, these conditions are rarely met these days, and specific
uncorrectable eye defects can make AF preferable (I've lost sharp
sight in the center of my "focus eye", damn!) much of the time
(macro work still makes it pretty useless, though).

BTW, I consider the AF indicators useless for accurate or convenient
focus (too much "slop"), and for fast action with small moving subjects,
AF hunting can make the use of AF impractical.

Also, BTW, this may not apply to you, but I find most optomitrists'
idea of how glasses should be set up rather poor - more useful for me
for age-related narrowing of the range of eye focus is a simple
glasses set up described here: www.ferrario.com/ruether/articles.html
(look down the index for "Four-Distance Glasses"...).
--
David Ruether
rpn1@cornell.edu
http://www.ferrario.com/ruether



Date: Tue, 17 Feb 2004 
From: Gordon Moat moat@attglobal.net
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: homebrew AF confirmation for non-AF kits? Re: AF mf camera

Bob Monaghan wrote:
> I think the major benefit of AF for many of us using MF would be
> confirming focus, esp. for low constrast scenes and wide angle lenses?
> Rather than buying new AF bodies and all new AF lenses, I would like to
> find a means to modify a prism or chimney finder to indicate in-focus or
> not using LEDs or whatever.

The Rollei 6008AF does indicate focus confirmation on many of the manual
focus lenses. I have not tried one, so I have no comments on how well
that works (or not).

>
> One of the pentax transitional 35mm SLRs ( ME-F, IIRC?) was an
> intermediate design with focus confirmation but w/o AF mount or lens
> control interface. The lights in the prism indicated in or out of focus.
>
> Has anyone experimented with a focus indication module to see if these
> can be reworked for standalone use (e.g., Nikon Multi-CAM530 autofocus
> module etc.)? Perhaps a simpler sensor from a low cost P&S; unit could be
> used too?

One weird idea is to use the module from a Polaroid SX70. These are
sonar autofocus, but they have a simple mechanical drive to move the
lens. Perhaps a rework of one could be rigged. The device is easy to
remove from the SX70.

Ciao!

Gordon Moat
Alliance Graphique Studio
http://www.allgstudio.com


From: stephen@stevedunn.ca (Stephen M. Dunn)
Subject: Re: Auto-Focus 101
Organization: Followers of Bokonon
Date: Fri, 30 Jan 2004 

Al Denelsbeck news@wadingin.net writes:
$ 'Passive' Autofocus - This uses a strip of light-sensors (yes,
$exactly like a digital camera) directly in the focus area of the
$viewfinder. The camera measures the variance between readings of adjacent
$sensors ('pixels' is incorrect but gives the right idea), and adjusts focus
$until the maximum contrast is achieved between them all. Since a focused
$image will be sharp-edged, high contrast, and an out-of-focus image will be
$fuzzy and low contrast, this works reasonably well.

Actually, contrast-based AF was an older technology that is seldom
used these days, at least in SLRs. Most modern AF SLRs use phase
detection. There are two sensors used, which catch light taking
different paths through the lens. If focus has been achieved, the
light projected on the two sensors forms the same patterns at the same
spot; if focus has not been achieved, the patterns will be the same or
similar but will be offset. The direction and magnitude of the offset
indicates how far out of focus the subject is.

Passive AF cameras often have AF assist beams. Some simply use
the flash to throw more light at the subject; these systems will
only work if the problem is insufficient light. Others use deep
red lights which project patterns of lines or crosses onto the
subject; the pattern itself becomes the target for the autofocus
system, and such a system can even lock focus on a featureless wall
in a perfectly dark room (not that you're likely to want to take a
picture of that :-) These red beams are sometimes erroneously called
IR; they are not. You can see them, which means they're visible
light (IR is invisible to humans). And since lenses tend to focus
IR at a different distance than visible light, a system which projects
IR on the subject, then views the result through the main lens, would
end up taking pictures which were slightly out of focus.
--
Stephen M. Dunn stephen@stevedunn.ca


Newsgroups: rec.photo.equipment.35mm
Subject: Re: Auto-Focus 101
From: Al Denelsbeck news@wadingin.net
Date: Fri, 30 Jan 2004 

"Lunaray" yar@easystreet.com wrote:
> Can someone explain to me how most of today's auto-focus cameras work
> (infra-red?), or can you aim me to a good tutorial? I'm specifically
> interested in how the Nikon F4 works. I couldn't find much on the web,
> though I'm sure that it's there somewhere. Thanks all!


There are actually two methods, and I don't know how frequently
either are used, though I do know what types of cameras use them.

'Active' Autofocus - This is the infrared version, which actually
uses infrared beams aimed at the object that are bounced back into a
receptor. The camera measures how much and how fast it receives the pulses
and computes a distance. Can get fooled by other IR sources, bad IR
reflectivity, or something like shooting through glass. It doesn't work at
greater distances, but it does work in the dark.

'Passive' Autofocus - This uses a strip of light-sensors (yes,
exactly like a digital camera) directly in the focus area of the
viewfinder. The camera measures the variance between readings of adjacent
sensors ('pixels' is incorrect but gives the right idea), and adjusts focus
until the maximum contrast is achieved between them all. Since a focused
image will be sharp-edged, high contrast, and an out-of-focus image will be
fuzzy and low contrast, this works reasonably well. But they need a certain
amount of contrast within the sensor area, which is why manufacturers warn
that vertical or horizontal patterns might fool the sensor; the strip is
oriented that way and has no contrast to read. It's also why you hear some
cameras have "cross-type" or "diagonal" sensors. Moreover, without adequate
light, they cannot get a decent reading. This level usually falls between
f5.6 and f8 through the lens. So you'll see most AF lenses never exceed
this as maximum f-stop (some go as high as f6.3 or 6.7), and
teleconverters, which cause light loss, will cause the AF to fail unless
they're used on fast lenses.

Most better camera models use Passive AF, since it's most accurate
and less easily fooled. It also works regardless of the lens used, since it
reads the image itself, not camera distance. Point-n-shoots are more likely
to be Active AF, though some of the better models use both methods in
conjunction - the camera will automatically choose whichever one produces
the results. At least one model digital (Sony F717) will illuminate the
subject in IR and read contrast from an IR-sensitive sensor, thus making it
a Passive IR AF. There are probably others, but this one I know about
firsthand.

Hope this helps,

- Al.


[Ed. note: Sigma lens AF incompatibility listings...]
Date: Mon, 24 May 2004 
From: "Pistol Pete" gregarpp@icqmail.com
Subject: Re: Sigma lens clarification

www.sigmaphoto.com

They have a list of lenses with problems on Minolta and Canon

"llarson100" wrote:
> Way, way uptopic there was some discussion on an issue regarding the
> compatibility of Sigma lens' and the Maxxum 7(?). Would someone
> please clarify that issue for me? I currently own a (beloved)600si
> and a Sigma 170-400 (among others) but am thinking of purchasing a
> 7. ALSO, is there a possibility of that problem (if it is indeed a
> problem -- why I'm asking) carrying over to the D7 since it seems to
> be patterned on the Maxxum 7 body? While the 7 is a highly
> regarded
> camera, I find myself really hankering for a D7. When I'm out
> shooting, the 600si and a Minolta S414 are with me, and find I'm
> getting spoiled with the ease of digital. And impatient for more
> news on the D7..
> Thanks for any reply.
> --Lynn



From: "Bob Johnson, Earthbound Light" bobj@earthboundlight.com
To: nikon@photo.cis.to
Subject: RE: [Nikon] shutter lag
Date: Sat, 17 Apr 2004 

> Once I saw a web site that lists the shutter lag of all
> theses different 35mm and DSLR cameras. Does anyone know the link?

http://www.fone.net/~rfrankd/CameraCompatibility6/CameraCompatibility6.htm

Bob Johnson
Earthbound Light
Nature Photography from the Pacific Northwest and beyond 
http://www.earthboundlight.com



From: "Neil Gould" neil@myplaceofwork.com
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: missing MF converts (lost to digitals) Re: ideal cameras?
Date: Mon, 07 Jun 2004


[SNIP]
That process isn't made easier by the time lag changing depending on
camera settings.

This is from the 828 review:

Action Details Time, seconds
Half-press Lag (0->S1) Wide angle (Multi / Center AF Area) 0.4 - 0.6
Half-press Lag (0->S1) Telephoto (Multi / Center AF Area) 0.6 - 1.2
Half to Full-press Lag (S1->S2) Wide angle (LCD / EVF) 0.1
Full-press Lag (0->S2) Wide angle (LCD / EVF) 0.2
Off to Shot Taken Wide angle 1.6
Shot to Shot Wide angle, Auto Review Off 1.3
Shot to Shot Wide angle, Auto Review On 3.0

Good luck predicting those pauses and anticipating the attractive
expressions. With my film cameras, I know *exactly* when the image will be
captured after pressing the button.



[SNIP]
> Currently, the printers are clearly better than either the digicams
> or the dSLRs at A4 and larger.
>
That says it all. ;-)

Neil



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