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The conventional wisdom on cleaning mirrors is DON'T!!!
Oftentimes, the dust (if in focus) is actually under your camera's screen
and may be blown out without risking damage to the mirror. If not, a
local camera store repairperson may be able to clean your mirror for a
nominal fee (often $10 to $15 is quoted). Some technicians use a special
cleaning solution (similar to collodion) to dry and pick up any dust on
the mirror.
Finally, CAVEAT Repairer! Some of the more modern cameras in particular
may have integrated electronics as part of the mirror, and cleaning
attempts may cause serious problems with metering.
The good news is that the dust that is driving you crazy in the
viewfinder won't show up on the film image. So try to forget it and
ignore it if you can!
From Nikn MF Mailing List:
Date: Mon, 02 Aug 1999
From: Rick Housh rick@housh.nu
Subject: Mirror cleaning
"LINUS TAY" linusjen@mbox3.singnet.com.sg wrote:
>A friend suggested using a cotton bud dipped >in Kodak lens cleaning fluid but warned me to be really gentle as the >mirror surface is soft...any comments?
I don't ever touch the surface of the mirror, unless there is a fingerprint
on it, or something else I believe will eventually be destructive to the
mirror's service if not removed. When I do, the method you describe above
is the one I have used, with universal success, although, for a cleaning
fluid I generally use about 50 ml of distilled water with one drop of
"hand" dishwashing detergent dissolved in it. I have found the small bit
of detergent to be necessary to emulsify the oil from a fingerprint.
However, I use no pressure at all on the "cotton bud," and blow off all
dust first, with a bulb or with compressed air. Any dust at all will
scratch the mirror. Let the fluid do the cleaning work. I generally use
the side, "fat" part of a "Q-tip" with no pressure, instead of the cotton
bud. I try to use the most expensive kind of q-tips I can get, as the
cotton fibers seem finer and softer.
After I feel the mirror is as clean as it is going to get, I repeat the
process using a q-tip with pure distilled water to rinse off the detergent,
then with a dry q-tip, until the mirror is thoroughly dry, always with no
pressure. If I can still see the fingerprint ridges when I breath on the
mirror, I repeat the process until I can't.
Although this method has worked the few times I have used it, and has made
the mirrors literally sparkle, without any detectable damage, it still
makes me nervous, and I don't recommend it unless absolutely necessary. I
tried it on a couple of "parts only" bodies several times before I tried it
on a working camera.
-- Rick Housh --
From Nikon Mailing List:
Date: Wed, 4 Aug 1999
From: Joseph Chiang Joseph.Chiang@trw.com
Subject: [NIKON] RE: Cleaning mirrors
Tim A,
Don't clean the mirror on your F4 (unless you get expert advise)! I did it
once and totally screwed up the timing on the mirror. Apparently the whole
reflex mirror system is quite delicately balanced and pressure placed on the
mirror can offset that balance. That is what I surmised after I cleaned my
mirror once (with a Q-tip moistened in alcohol) and caused it to become so
slow that, even at high shutter speeds, the camera would no longer frame
advance at maximum fps. The best thing to do is have a Nikon service center
do a thorough cleaning.
Joe
From Hasselblad Mailing List;
From: "Joe Codispoti" joecodi@thegrid.net
Date: Sun, 9 Jul 2000
Subject: Re: Reflex Mirror Cleaning
Vick,
ROR (Residual Oil Removal) is a lens cleaner whose active ingredient is
ammonia. You can check the web page at:
www.ror.net/index.html
You might also check ClearSight on my page:
http://www.thegrid.net/joecodi/clearsight.html
Cheers,
Joseph Codispoti
From hasselblad Mailing List;
Date: Sat, 08 Jul 2000
From: Vick Ko vick.ko@sympatico.ca
Subject: Re: Reflex Mirror Cleaning
I did it on a very old body of mine.
Here's what I did:
1) use KODAK lens
2) used lens cleaning fluid
3) dropped a couple drops of fluid onto mirror (in up position)
4) folded lens paper into rectangular wad and VERY VERY VERY carefully
swished fluid around all of mirror
5) do not apply any finger pressure - use the stiffness of the
rectangular wad only
6) take a second DRY sheet of lens paper, and make another rectangular
wad
7) tear off one end, to make a torn edge - like a paint brush
8) use that to dry the mirror
9) cock the mirror and let it dry (1 hour). DO NOT fire the body - you
will
get splashes of fluid on the mirror again. This method gets fluid
into
spots that you can't dry, and must let air dry
Since it was an old body, and getting frustratingly annoying, this
worked out
well.
Raymond Wong wrote:
> Does anyone know what is the best way to clean the Hassey's reflex > mirror?I know it is not something one should do all the time. But > there are situations where one just cannot stand it any more. Do I use > lens cleaners?Q-tips? Kodak lens paper?Water? Any > idea/suggestions/experience will be much appreciated. Raymond Wong
From Hasselblad Mailing List:
From: BobR38@aol.com
Date: Sat, 8 Jul 2000
Subject: Re: Reflex Mirror Cleaning
Ray,
Personally when cleaning mirror, I will only use a very soft brush and don't
apply any pressure at all. Since the mirror is internal, the only particles
that it seems to attract are dust, so I've never had the need to use any
fluids for cleaning. When using tissues or cloths, I'm afraid that a tiny
particle can cause a surface scratch to the mirror, and I therefore avoid
this technique, but this is only my method of cleaning.
Bob R.
From: InfinityDT@aol.com
Date: Sat, 8 Jul 2000
Subject: Re: Cleaning with Microfiber?
To: paolop@snet.net, hasselblad@kelvin.net
paolop@snet.net writes:
I have heard a lot about cleaning lenses with Microfiber cloth, but
where does one get it?
Also, is the method:
(1)blow dust off
(2) wet Kodak tissue with Kodak Lens cleaner, and gently clean,
(3) final pass with Microfiber cloth...
the recommended method for cleaning the beautiful Hasselblad lenses?
Microfiber cloths are available in almost every camera store and photo
department in department stores, plus through all the major mailorder houses.
You can use them with or without lens cleaner (I recommend ROR, it contains
ammonia which cuts any grease, like fingerprints, whereas most alcohol-only
cleaners just smear them). My personal preference is to keep a Hasselblad
UV-Haze filter on all lenses all the time (except shooting into the sun or
when using another filter). I can clean those filters as often as I wish
with most any kind of cloth, and as long as I'm reasonably careful they don't
get scratched. I once gently cleaned a 50 C T* with (I thought) a clean lens
cloth after blowing (I thought) all the dust/grit off with a blower and then
breathing on the lens. When done, there were circular scratches in the
coating. Somewhere there was a speck or two of grit I hadn't seen. Since
then, the "image degradation of UV filters argument" has bowed to the $1100
cost of replacing that front element.
From Hasselblad Mailing List:
From: InfinityDT@aol.com
Date: Sat, 8 Jul 2000
rwong@powersurfr.com writes:
Does anyone know what is the best way to clean the Hassey's reflex
mirror?
I know it is not something one should do all the time. But there are
situations where one just cannot stand it any more.
The most that should get on it is dust, which can be blown/brushed off with a
bulb blower/soft camel-hair brush. If there's anything left on the mirror
like spots, you could clean it *very very gently* with a drop of ROR on a
microfiber cloth wrapped over the tip of your finger. Then consider using a
body cap whenever the lens is off the camera. Those mirrors scratch a lot
easier than a lens.
From Hasselblad Mailing List:
From: "Joe Codispoti" joecodi@thegrid.net
Date: Sat, 8 Jul 2000
Subject: Re: Cleaning with Microfiber?
>My personal preference is to keep a Hasselblad > UV-Haze filter on all lenses all the time (except shooting into the sun or > when using another filter). I can clean those filters as often as I wish > with most any kind of cloth, and as long as I'm reasonably careful they don't > get scratched. I once gently cleaned a 50 C T* with (I thought) a clean lens > cloth after blowing (I thought) all the dust/grit off with a blower and then > breathing on the lens. When done, there were circular scratches in the > coating. Somewhere there was a speck or two of grit I hadn't seen. Since > then, the "image degradation of UV filters argument" has bowed to the $1100 > cost of replacing that front element
Breath does not provide enough liquid to emulsify the dust on a lens. The
use of a good liquid cleaner with emulsifiers in its formula will avoid or
at least minimize cleaning problems.
Most of the grit in a cloth is attracted in storage. Keep the cloth in a
zip-lock bag.
Any cloth must be washed often to eliminate whatever grit may have become
trapped in it; change the bag from time to time as well.
Lens tissue also should be kept in a zip-lock bag.
Lenses should be cleaned after each assignment. They should be checked
frequently for dust etc. The lens cap is the best insurance against
accumulation of dust (don't forget to remove it prior to shooting....smile).
My cleaning kit consists of camel hair brush, blower (ear syringe), liquid
cleaner (ClearSight of course), and microfiber cloth; all kept in a plastic
zip-lock bag.
Joe
From Hasselblad Mailing List;
Date: Sat, 08 Jul 2000
From: "Paul B. Hill" pbh@MIT.EDU
Subject: Re: Reflex Mirror Cleaning
I'm not so sure that the method described in the earlier posting is such a
good idea. The object to be cleaned is a front-surfaced mirror. This means
that the rubber cement is placed in contact with the reflective surface,
not the glass. I don't know the adhesive strength between the reflective
surface and the backing material, but if it is weaker than the bond between
the rubber cement and the reflective surface, pealing the cement off would
take the reflective coating as well. Not exactly the desired outcome.
In general the only group of people that are more meticulous about the
cleaning of optical surfaces than photographers are scientists. The
astronomical community is pretty good, they like accurate results. People
that deal with high powered lasers tend to be even more careful; in their
case damaged optics can damage other equipment, or even people. (A poor
surface can lead to absorption of the energy, which can in extreme case can
cause the material to fracture spectacularly.)
Try searching at www.google.com with the search terms: cleaning optical mirrors
You find one document from Newport and some advice from various educational
labs to their students and staff. I recommend reading a number of the pages
returned so that you can see the variety of opinions and recommended
techniques. When I worked in a laser lab we only used optical grade
acetone on front-surfaced mirrors, but as you can see others have other
preferences.
BTW, I also tried the same search as above but added "rubber cement" as
search terms. A number of documents were returned but on a cursory
inspection I didn't find any that suggested the technique that was
suggested by the earlier posting to the list.
Paul
Raymond Wong wrote:
>Good idea, Joe: >Will try this. > >Thanks > >Ray >>----- Original Message ----- >>From: mailto:joecodi@thegrid.net Joe Codispoti >>To: mailto:hasselblad@kelvin.net hasselblad@kelvin.net >>Sent: Saturday, July 08, 2000 >>Subject: Re: Reflex Mirror Cleaning >> >>I had always heard that the best way to clean a front-surfaced mirror is >>to cover it with rubber cement. Once the cement is dry, peal away and it >>the grit and dust goes with it. >>I have tried it once but cannot remember whether the result was worth the >>trouble. >> >>Cleaning with a cloth or paper is not good for it will scratch the >>mirror. I clean with a cotton swab barely moistened with alcohol making >>sure that I swab very gently. >>So far I have had no problems with this system. >> >>Joe >> >>>----- Original Message ----- >>>From: mailto:rwong@powersurfr.com Raymond Wong >>>To: mailto:hasselblad@kelvin.net hasselblad@kelvin.net >>>Sent: Friday, July 07, 2000 >>>Subject: Reflex Mirror Cleaning >>> >>>Does anyone know what is the best way to clean the Hassey's reflex mirror? >>>I know it is not something one should do all the time. But there are >>>situations where one just cannot stand it any more. >>> >>>Do I use lens cleaners? >>>Q-tips? Kodak lens paper? >>>Water? >>> >>>Any idea/suggestions/experience will be much appreciated. >>> >>>Raymond Wong
From hasselblad Mailing List:
From: "Charles Jay Pilzer" cjp@ursaco.com
Date: Tue, 11 Jul 2000
Subject: RE: Reflex Mirror Cleaning
A Hasselblad technician told me to use scotch tape. Apply it carefully over
to spot that you want to clean and remove it. Do not use any method that
causes you to wipe anything across the mirror surface.
cj
From Hasselblad Mailing List;
Use nothing other than air from an ear bulb. The under side is a plastic
lens. Almost all fluids will damage. Any friction will also.
cj
From: "Ric Trexell" rtrexell@vbe.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Cleaning SLR mirrors
Date: Wed, 4 Dec 2002
David Nebenzahl nobody@but.us.chickens wrote
> If I ask "how do you clean the mirror?",
David: I would say this. I attended the National Camera Repair school when
it was in operation in Denver. (Actually Englewood.) We were taught to use
acetone on a wooden or paper Q-tip. The acetone evaporates super fast.
Alcohol can bead up and if you use a plastic Q-tip you might get a blue
streak on the mirror. If you use acetone you certainly will get a streak.
I would never use any more pressure than the weight of the Q-tip. (Well, ok
I would sometimes use a little.) The best cleaning agent is air from a
blower brush or something not too hard. Canned air can sometimes get the
propellant on the mirror I have heard. I have never used it for that
reason. Remember that unless it really bothers you, it doesn't have any
affect on the actual picture. When it gets really bad, either have a pro do
it or buy a new camera.
Ric in Wisconsin.
From: "Mike Elek" melek@fptoday.com
Newsgroups: rec.photo.equipment.35mm
Subject: Re: Cleaning SLR mirrors
Date: Thu, 5 Dec 2002
Several of my cameras needed the foam seals replaced. The foam had turned to
goo, and with a Nikon EM, the foam would cause the mirror to stick to the
pentaprism housing for several seconds.
I used rubbing alcohol and a large number of facial tissues to remove the
goo. It worked well, and it didn't mar the surface. While generally you
shouldn't mess around with it, if you're careful, you can clean it correctly
without scratching the surface.
--
Mike Elek
[Remove 'NOSPAM' from the e-mail address]
See my camera collection:
http://host.fptoday.com/melek/pages/cameras.html
From: "MJR" mjrodney@comcast.net
Newsgroups: rec.photo.equipment.35mm
Subject: Dust & the digital SLR - A Canon recommendation
Date: Sat, 7 Dec 2002
Earlier this morning, I attended a photographic event where Canon
Technicians were available to clean and confirm the proper operation of
attendee owned Canon cameras and lenses.
A Canon technician quickly made the announcement to a rapidly growing line
of photographers that they would be unable to remove a lens or a body cap
from any D30 or D60 SLR for an interior cleaning.
The technician explained that the CCD element is a natural dust magnet and
remains electrically "charged" in the same sense as the face of a television
screen (CRT); particularly so when the camera is on, and for an unspecified
time after the camera is turned off. This natural charge is a dust magnet.
Canon did not want to take any responsibility for dust falling onto the CCD
by way of their opening the camera and/or by stirring things up with a can
of compressed air and a cotton tipped swab.
This was followed by a "recommendation" to the D30 and D60 owners, advising
them not to leave the body open for any longer than it takes you to change
the lens. In a dust blown environment, where dust is likely to be swirling
about, it was recommended that you do not remove a lens or body cap at all,
unless you are willing to have the camera professionally serviced on a
regular basis.
Cleaning of the CCD element must only take place in a controlled, dust
conditioned environment, with the proper equipment and with the proper
solutions, that are designed for the purpose. In other words, he
recommended, don't try cleaning the inside of the camera body at at home. At
the very least, you may cause dust to fall on the sensor. At the worst, you
could damage the mirror (if you can get it up with the lens off) and damage
the CCD, a problem the warranty will not cover. His vocal emphasis was
intended to convince us all of the fragility of that CCD sensor.
On the plus side, the Canon rep offered one week turn around on D30's and
D60's sent in for proper cleaning. I didn't ask how much a clean and
calibration was to cost.
One might think the Technician was only trying to promote Canon's
professional cleaning services; but at 2K plus a pop for these cameras, I'm
inclined to believe him.
Every 3 months or 3000 miles........just like the car.
From: brianc1959@aol.com (brian)
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: MIRROR LENS Special problems
Date: 21 Jan 2003
...
Bob:
When you put a cutout in front of a catadioptric lens the cutout
*becomes* the aperture stop, and the DOF is increased accordingly.
Essentially what you are doing is creating an unobscured system with a
front stop. The main problem when you do this with a 500/8 is that
the f/# gets really large, which will cut down the resolution. If you
want to do this trick a 500/5 would be a better choice to start with.
Brian
www.caldwellphotographic.com
From: Tom Dove tomdove@toadmail.com
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: MIRROR LENS Special problems
Date: Fri, 17 Jan 2003
> from: flexaret2@aol.com (Sam Sherman) 1-17-02
>
> Anybody know about the special problems in using mirror lenses,
> including going from warm indoors to cold outdoors and not
> being able to get sharp photos.
>
Yep. What you're experiencing is the problem that astronomers have with all
catadioptric telescopes (your mirror lens is probably actually a small
Maksutov telescope). The optical tube is enclosed, and it takes some time
for the air inside it and the glass elements to cool. Until that happens,
air currents inside the tube alone will cause all sorts of optical problems.
My 5-inch diameter Mak telescope, for example (1540mm focal length, F/12.1)
typically requires an hour to accomodate from indoor temperature to outdoor
temperature at this time of year. Photographic mirror lenses are smaller
than that, so they'll cool faster. Still, I wouldn't be surprised to find
that a typical 500mm catadioptric lens might take 20 minutes to stabilize
outdoors.
Dew formation on the front element can also be a problem, but that's visible.
--
-- Tom D
From: john@stafford.net (J Stafford)
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: MIRROR LENS Special problems
Date: Sat, 18 Jan 2003
hartmut@mail.ru wrote:
> Apart from this, I've found that a major drawback of the mirror
> lens is the missing diaphragm.
Has anyone tried adding an aperture. I propose something like this:
http://wind.winona.edu/~stafford/mla/
From nikon mailing list:
Date: Mon, 20 Jan 2003
From: Irving Birkner iabirkne@uchicago.edu
Subject: Sigma 600 Mirror lens
Hello,
A few months ago, I found a pretty good deal on a Sigma 600 f/8 mirror lens
on eBay (~$120 or so) and went looking for opinions on the lens from this
list and on google. There wasn't much, but what I found were mixed opinions
on mirror lenses themselves. Since the topic comes up on the list every so
often so I thought I'd give a brief review now that I've had a chance to
use it. I am presenting my opinion as fairly serious but still amateur
photographer. A 600 f/4 or a Nikon mirror lens wasn't really an option
thanks to the lack of free graduate school in the US, and the nearest focal
length lens I had before this was a Sigma 75-300 4-5.6.
First, the lens itself. It's well made, with a good tight focusing ring and
it mounts securely to my F2 Photomic. It's actually not much longer than a
105 2.5, but it's about a 95mm filter ring (you drop filters in the back)
-- and when you add the included metal lens hood to the front of lens, it's
a huge set-up. You won't be able to drop it in your camera bag. Even with
the hood reversed, I had to rearrange the dividers in my big Tamrac bag to
get it to fit.
One thing that I didn't see emphasized in any reviews was that at 600mm,
your depth of field is nil, even at a fixed aperture of f/8 (duh! say you
pros). It can be hard to get precise focus with this lens -- which is
aggravated by its size -- if you were standing in a bright field, you might
be able to hand hold this, and get reasonable shutter speeds. For every
other situation, you need a tripod.
The biggest issue with the lens is always the bokeh (out of focus areas)
one gets with a mirror lens. It's definitely not as nice as my 105 2.5, but
it seems like if you use it carefully you can do pretty well (at least I
think so. Maybe my standards are low).
Anyway, here's some pictures I took at the Lincoln Park Zoo using this lens
on my F2 with Fuji 400 Superia mounted on my Bogen Jr. tripod. The shutter
speeds were around 1/125 or 1/250 sec. Definitely not fast enough to
capture action, but since it was really cold, nothing was moving much. The
scans are unretouched (note the dust, sigh) from my HP 3500c.
http://birkners.org/images/newscans/eagle600.jpg
http://birkners.org/images/newscans/eagle2600.jpg
http://birkners.org/images/newscans/specbear600.jpg
Actually, looking at the bear's eye, I think this one isn't focused as well
as it could've been.
Irving
From: danielwfromm@att.com (Dan Fromm)
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: Lenses - yesterday, today and tomorrow
Date: 19 Jun 2003
Mxsmanic mxsmanic@hotmail.com wrote
> Bob Monaghan writes:
{snip}
>
> I've always read that mirror telephotos were relatively poor performers
> optically, anyway.
Bob, this is a little off topic because the lens just barely covers
24x36, but don't despise the humble Questar 700.
At 1:4 with flash illumination mine produces slides that can't be told
from ones made with at 1:4, f/8, flash with a 55/2.8 MicroNikkor. It
is, like all long lenses, an absolute son of a bitch to use
out-and-about, demands more steadiness than I can often provide.
Cheers,
Dan
To:
Subject: RE: Cleaning Acute Matte Focussing Screens
> -----Original Message-----
> From: Ken Brass [mailto:mckandb@ozemail.com.au]
> Sent: Monday, July 10, 2000
> To: hasselblad@kelvin.net
> Subject: Cleaning Acute Matte Focussing Screens
>
>
> Great to get so many good ideas for cleaning mirrors, but I'd
> still like to
> know the best way of cleaning Acute Matte focussing screens.
> Mine are a bit
> grimy and I'm worried about either scratching them with a
> cloth or damaging
> them if I use a chemical. Cheers
> Ken