Related Links:
Field Flash X-synch Test
Fill-in, Flashguns, and FP Shutters
Flashbulb in Caves.. (5/2003) Megaflash Flashbulbs Source
Underground Photographer Flashbulb Resource Page (added 3/24/99)

Flashbulbs can provide an extra set of problem solving tricks for you if you use a focal plane shutter medium format (or 35mm) camera. Cameras such as the Bronica S2a/EC and Pentax 6x7 are examples of focal plane shutter medium format cameras. These cameras typically have a slow flash synch speed, due to their large cloth shutters having to uncover a 6x6cm square film area. Unlike leaf shutter cameras, most focal plane cameras have flash synch speeds ranging from 1/30th to 1/90th second, with the range from 1/45th to 1/60th second being typical.

The problem is that you would prefer to have a faster flash synch speed in many brighter lighting situations to prevent ghosting. Ghosting happens when there is so much light that your slow flash synch speed (e.g., 1/60th second) provides a second exposure. This second or ghost exposure is often blurry if the subject was in motion. Your sharp strobe photo is ruined by the second ghost image.

Leaf shutter lenses provide flash synch at any speed, providing more flexibility. You can use a faster flash synch speed up to 1/500th second, and eliminate or minimize the ghosting effect.

Many focal plane shutter systems provide one or two lenses in their lineup which have a leaf shutter built into them. Examples include the 105mm leaf shutter nikkor for Bronica S2a/EC series and several leaf shutter lenses for the Rollei SL66. But using these dual shutter option lenses is often cumbersome, and they are expensive as well due to the built-in shutter. Moreover, you usually only get a few lens choices, usually a short telephoto for portraiture being most popular.

You can mount lenses in shutters in adapters to fit your focal plane shutter camera. Many older folder and press camera lenses will cover medium format 6x6 to 6x9 quite easily. Costs are low. See Homebrew Lenses for details.

But most focal plane cameras have a hidden fill-in flash synch option. They can take FP or focal plane flashbulbs. These FP flashbulbs put out a longer blast of light than the instantaneous flash of an electronic strobe.

If you pick a faster shutter speed up to 1/1000th of a second, these FP bulbs will provide a very bright light source during the entire exposure time.

Understand that the actual exposure time is much more than the 1/1000th of a second period, which is governed by how far apart two shutter curtains are during the exposure. The actual time for the shutter curtains to move across the 6cm film plane is still about 1/60th second or so. But the focal plane flashbulbs put out a relatively continuous amount of light during this entire 1/60th second period.

A few sophisticates studio strobe units solve this problem by flashing hundreds or thousands of times during this shutter traveling time (1/60th second etc.). Each short flash exposes a small strip of film, which taken together yields a uniform exposure. Unfortunately, even such specialty strobes are only able to perform this trick at very limited distances, due to the huge amount of power needed to flash hundreds of times in 1/60th of a second or so.

Flashbulbs aren't a replacement for electronic flash in general use. Yes, they are bulky and expensive per shot. However, they are lightweight, and put out a whole lot of light. You might have to pay hundreds of dollars to get an electronic flash as powerful as a small flashbulb. The larger flashbulbs put out more light than most studio flash setups!

A pro photographer friend shooting a corporate report needed to light up a train in a daylight shot for an annual report. Trains are rather big, too big to bring into his studio. The cost of electronic strobe rentals for such a project was much more than the cost of three #5B flashbulbs needed for the shot. The flashbulbs were a compact source of a lot of light, and provided the freedom of fill-in flash synch at any speed too. Unfortunately, we had to make several polaroid test shots, and so it took an armload of flashbulbs and a bit of running around to make it happen. But at least I know how to light a train now!

My own experience with flashbulbs has mainly been in underwater photography, using flashbulbs with both my housed Bronica S2a and nikonos underwater cameras. You lose a lot of light underwater, so a powerful light source is needed. You also want fill-in flash options. Mixing fill-in flash with sunlight in shallow water provides the most depth of color and background light. Unfortunately, the little fish in shallow water tend to move fast, so you can't use a slow flash synch speed without ghosting. You need a fast shutter speed shot to freeze their motion. Enter the focal plane flashbulb as a solution to this problem. Now you can balance your fill-in flash with the ambient light at a speed fast enough to freeze your fast moving fish. The original nikonos flashbulb unit was very popular, with many divers taking a mesh bag full of flash bulbs underwater to shoot a roll of film.

In short, flashbulbs are a potential solution to infrequent fill-in flash needs. If your focal plane shutter camera system doesn't support a desired lens focal length in a leaf shutter mount, flashbulbs may be a solution.

You can buy a flashbulb holder for very low cost, as they are unpopular. Bill Cress offers flashbulbs at his site (see Links table). You can also buy them for sale at EBAY and other online sites, again very inexpensively. Many pros stock up at these close-out prices to prepare for that future job where flashbulbs offer the cheapest, lightest, and lowest cost solution.

Another use for flashbulbs is the immense amount of light the larger flashbulbs can put out. We have already suggested that when you need to light a really big object like a train or conference hall, flashbulbs may solve that problem. Due to their lightweight, flashbulbs are also very handy for lighting up caves and other remote sites. Here, electricity and large strobe packs would be hard to pack in and dangerous to setup (e.g., due to wet ground or standing water).

Flashbulbs are often fired by small voltage batteries, and can even be used in simple holders underwater. The next time you have to light up the bottom of a nuclear submarine, keep this in mind!

What if you need to light up a large building, or a mammoth underground cave. Your calculations show you need dozens or hundreds of flashbulbs to make it happen. Some nuclear bombs put out less light than you need, what to do? The answer may lie in flash-powder, that old time magnesium based ultra-bright light source.

Flashpowder was used by photographers with painted on emulsions in the ASA 0.1 to 2 range and view camera lenses that performed best at f/45. No problem! A little flashpowder in the pan, and poof - your lighting problem was solved.

Several companies used to offer magnesium photographer's powder in the near past (late 70s), but neither seems to do so anymore. Still, you can buy magnesium powder from some chemical supply houses and make your own. You need to observe various safety precautions in using it, which I can not elaborate here (e.g., static electricity is a no-no). Considerable care is needed in handling and storing flashpowder, as is probably obvious to you already why!

But flashpowder is simply the brightest no-nuclear source of light you are likely to get your hands on. A kilogram of flashpowder is brighter than a thousand flashbulbs the size of 150 watt light bulbs! Now that's a lot of light. You will usually use more like under an ounce for dazzling effects to light up a cathedral.

In summary, don't forget that flashbulbs are often part of your classic medium format camera's capabilities. Flashbulbs offer a low-cost way to solve infrequent fill-in flash synch problems. You can also count on them to provide an immense amount of light with minimal weight and cost. The low voltages needed are also handy in some environments (underwater, wet caves).

Finally, don't forget those old timers with their ASA 1 film and f/45 lenses use of flashpowder lighting. You would need dozens or hundreds of studio strobes for the same amount of light from a handful of flashpowder. The next step after that requires a tactical nuke!

Related Postings

Meggaflash Technologies Ltd. is an Irish company which still manufactures flash bulbs and distributes them world-wide. Flashbulbs are used in a number of applications including large and medium format photography, high speed photography, special effects and many more. Please visit web site http://www.meggaflash.com for more information on the range of flash bulbs manufactured or email meggafla@iol.ie with any questions.

Are there particular flashbulbs you would require and would like to be manufactured - please let us know!!!

Postings:

Date: Fri, 19 Mar 1999
From: TLC tomclark@sprynet.com
Reply to: hasselblad@kelvin.net
Subject: Re: Flash for SWC

Another technique to try is multiple flash with the shutter set on B. You can wear a head-to-toe black Ninja suit and walk around inside the cave with your electronic flash in hand popping away here and there to light up all the nooks and crannies.

Tom Clark

-----Original Message-----
From: LEO WOLK bigleo@worldnet.att.net
To: hasselblad@kelvin.net hasselblad@kelvin.net
Date: Friday, March 19, 1999
Subject: Re: Flash for SWC

>Have you tried flashbulbs?  One of the larger screw-base types (#3 or #22 or
>#50, etc) would give you this kind of coverage.  Speleophotographers
>routinely use flashbulbs, it's the prefered method of illuminating those
>large cave interiors.
>
>Best,   Leo.    
>
>
>-----Original Message-----
>From: Dr. Ulrik Neupert 
>To: hasselblad@kelvin.net 
>Date: Friday, March 19, 1999 
>Subject: Re: Flash for SWC
>
>
>>> What subjects do you plan on shooting with the flash/wide angle?
>>
>>Different subjects. Nature, caves, interior of houses for insurance
>companies, etc..., non professional, just for my pleasure.
>>
>>Many thanks for the answers so far
>>
>>Ulrik   

From Hasselblad UG:
Date: Fri, 19 Mar 1999
From: LEO WOLK bigleo@worldnet.att.net
Subject: Re: Flash for SWC

While I don't have the specs for all bulbs in front of me, at hand I do have them for 25B and M3B, two popular types. Both indicate that they can be used with "X" or "M" sync up to 1/30, after that they are to be used on "M" sync only. Of course, there's always the "B" setting!

I think the limiting factor on most flashbulbs (or electronic flash, for that matter) is the reflector. Most reflectors are designed to be confining, that is to throw the light in a fairly narrow beam. I think if you could devise some kind of flat reflector for the flashbulb, or bare flashtube, you could get the coverage you'd need. However you'd have to make some kind of exposure compensation off published guide numbers, to allow for the greater diffusion of the light.

Most speleophotographers use open flash...that is, open the shutter in a black room, fire the flash, close the shutter. This also allows for "painting with light" that someone else mentioned.

Best, Leo.

From: Meggaflash Technologies meggafla@iol.ie
Newsgroups: rec.photo.equipment.large-format
Subject: New flashbulb - PF50
Date: Fri, 04 Jun 1999

Meggaflash Technologies Ltd. is pleased to announce a new addition - the PF50, to it's current range of photographic flashbulbs. The PF50 is a smaller flashbulb than the other bulbs manufactured by Meggaflash and is better suited to large or medium format photography.

Why not visit our website for more information? http://www.meggaflash.com

Date: Mon, 24 Jan 2000
From: AKroehle@aol.com
To: rollei@mejac.palo-alto.ca.us
Subject: Re: [Rollei] Flash cubes needed

These two sources may have what you're looking for:

Wagon Photo Sales at 1-800-343-3290

-or-

Bill Cress
PO Box 4262
Wayne, NJ 07474-4262
tel 973-694-1280  fax 973-694-6965
e-mail at wcress@ix.netcom.com or website at www.flashbulbs.com

Hope this helps!

Alice Kroehle

Date: Mon, 29 Nov 1999
From: Ron Klein panorama@gci.net
To: panorama-l@sci.monash.edu.au
Subject: Re: Flash Pans

> There is no slit panorama flash photography, period.

I know and old cirkut photographer that used a long row of flash bulbs that were touching each other. When the first one was fired, the others would self ingnite one at a time. His only complaint was that the people on the end of the photo all had their eyes shut. I wonder why.....

Ron in Alaska

From Rollei Mailing List:
Date: Sat, 22 Jan 2000
From: Jon Hart jonhart51@yahoo.com
Subject: Re: [Rollei] Off topic: uses for flash bulbs

--- "imagineero ." imagineero@hotmail.com wrote:

> One more point, just out of curiosity; do these long
> burning bulbs have a
> fairly consistent output during their burn or does
> it peak and then fall
> off?

Shaun,

The M synch bulbs (such as Press 25's, 5's, M3's, et al.) were made to peak at the 20-30 millisecond delay, whereas the FP bulbs had a very long, relatively straight burn in comparison. As I recall (probably wrongly), synch delay for FP was adjustable on a number of cameras to take advantage of the full light output.

Jon
from Deepinaharta, Georgia

From Rollei Mailing List:
Date: Sat, 22 Jan 2000
From: Richard Knoppow dickburk@ix.netcom.com
Subject: Re: [Rollei] Off topic: uses for flash bulbs

you wrote:

>>Other uses beside trains are stately homes i.e. large buildings
>>which are not lit up at night.
>>On a more tecknical note flash bulbs can be used to get around the
>>maximum shuter speed limitation of focal plane shuters as unlike
>>electronic strobe for the period that they are firing they are a
>>continious light source.
>>This also would make them usefull with a high speed motor drive as
>>they get round the problem of lash recharge time.
>>Some bulbs can burn for as long as 3 seconds.
>>Finally and related to the above theyre used for much the same
>>reasons for very high speed movie work such as watching the volvo
>>hit the wall, the rocket go by etc.. apparently nasa buy them by the
>>pallet load!
>>Hope this helps
>>Larry Cuffe
>
>Indeed, that was very informative.  Thanks for the tips Larry.  I knew of
>their high power, but had never though of the possibilities as a continuous
>light source with high speed cameras.  Too bad you'd have to stop shootping
>every 3 seconds to change flash bulbs....  I am sure it is possible to rig
>some kind of contraption that would fir them in a series at a pre-determined
>interval.  Given todays modern SLR's, you could go through a whole film in
>around 4 seconds with just 2 flashbulbs.  Hardly my cup of tea though I must
>say.  I'm happy enough with my flex and 12 shots :-)
>
>One more point, just out of curiosity; do these long burning bulbs have a
>fairly consistent output during their burn or does it peak and then fall
>off?
>Thanks again
>Shaun
>South Korea

The bulbs used by NASA must be specials, none of the standard bulbs will burn for anything like three seconds. For high-speed motion analysis photography arrays of flash bulbs triggered sequentially have been used to produce fairly steady light of very high intensity for a couple of seconds.

This may be what is being thought of here.

The half-peak intensity duration of ordinary Class-M bulbs is around 13 or 14 miliseconds (General Electric data). Bulbs made for focal plane shutters, Class-FP have extended peaks. Those made for use with 35mm and other small cameras have 1/2 peak durations of around 27 milliseconds. The GE #31, intended for use with 4x5 Speed Graphics has a duration of 53 milliseconds. The output is reasonably flat but _icreases_ slightly as it burns, probably to compensate for the acceleration of the shutter curtain in these cameras. This was about the longest duration bulb made. Focal Plane bulbs had a delay of 15ms between firing and reaching 1/2 peak output. Standard Class-M bulbs reach their peaks at 20ms. The synchronizer was generally set so that the shutter would be wide open at its highest speed whe the bulb reached its peak. When using slower speeds a shorter delay would result in a somewhat greater amount of useful light. The only shutter I know of which took advantage of this is the Wollensak Rapax, also sold as the Graflex Graphex. It has two settings for Class-M bulbs.

Mid 1940's prices were about fifteen to twenty cents per bulb.

----
Richard Knoppow
Los Angeles,Ca.
dickburk@ix.netcom.com

From Rollei Mailing List:
Date: Sat, 22 Jan 2000
From: Jon Hart jonhart51@yahoo.com
Subject: Re: Re: [Rollei] Off topic: uses for flash bulbs

--- ShadCat11@aol.com wrote:

> Altho I burned off thousands of the little bastards
> during the 50s and until
> @ 1967, I consider electronic flash to be a better
> alternative and don't miss
> flashbulbs at all.

Frankly, neither do I except for those occasions when I could use them to light very large, dark spaces. Of course, these are few and far between. To tell the truth, the last time I used them seriously for just such an occasion was back in around 1976 when I used them to light up the interiors of the walls of old Fort Mifflin in Philadelphia. That type of firepower was required in this context. I recall using 3 different bursts of 2 or more bulbs with the shutter set on Bulb in order to get the depth of field required. Everything was done by touch in the dark.

What a job! What nicely fried fingertips! A lot of knowledge penetrated this thick skull with that shoot! Oh well, live and maybe learn. As to the AG-1's, they were very convenient compared to the Press 25 or 5. You didn't lose that much light going to them, especially if you got hold of the adaptor that fit into the socket of the 25's reflector and allowed you to use them in the place of 25's or 5's. As a matter of fact, I still have it in one of my "junk" boxes. I came across it the other day and thought about how I used to utilize it. And also how the shots I took with it are no longer with me, thanks to a person who shall go nameless, here.

Jon (Gramps for the third time)
from Deepinaharta, Georgia

From Rollei Mailing List:
Date: Sat, 22 Jan 2000
From: Jon Hart jonhart51@yahoo.com
Subject: Re: [Rollei] Off topic: uses for flash bulbs

.....

Richard,

I believe that one of the big points of the Copal Square shutter in Konica T's and A's was its ability to use the full capacity of flash bulbs at the slower shutter speeds. In what manner they did this I haven't the foggiest. Just that they worked. I used them for this purpose back in the 70's.

One other point that may be of interest, as to FP bulb burn time, I seem to recall (faultily, no doubt, as it has been rather a long time) that #2 bulbs were made for some ungodly long burn times (as well as blinding the model and photog) in the studio setting.

My venerable Kodak Professional Photoguide c.1975 states a guide number (in feet) of 150 with E.I. 25 and an output greater than 16,000 BCPS. The #2 was not FP while the 6B and 26B were and had BCPS of about 6,000 with guide number of approx. 90. They were not of particularly long burn time, as I remember, nor over-great power even when used in their relatively huge reflectors. These power ratings are at 1/30 sec. or shorter shutter speeds. Ever use any of these?

Jon
from Deepinaharta, Georgia

From Rollei Mailing List:
Date: Thu, 20 Jan 2000
From: Richard Knoppow dickburk@ix.netcom.com
Subject: Re: [Rollei] Flash Synch

you wrote:

>Just out of curiosity, what types of applications are people finding for
>these bulbs?  Although they are a cheap (in the short term) method of
>obtaining large amounts of power, who really needs that much power?  I have
>heard that cavers use them.  Are there any list members using them on a
>rollei?  Is it simply the novelty appeal?
>
>Shaun
>South Korea
>
>>They still make flash bulbs in Ireland.

The Irish made bulbs are expensive. A little searching will find tons of old bulbs at more reasonable prices.

Flash bulbs have the advantage of power and very light weight. The guide number for a GE #5 bulb, one of the smaller ones, for ISO-100 film at 1/100th sec shutter speed is about 200. The #50, a biggie meant to be used in studio reflectors with open flash has a guide number of 600 for ISO-100 film. The Sylvania (formerly Wabash) Press 40 has a GN of around 360 for ISO-100 at 1/100th sec. Strobe units which can match this are pretty large.

OTOH, having had to use bulbs when there was no other choice I can say they were a PITA. Expensive and a mess. Good flash holders would spit out spent bulbs without having to touch them but sometime they needed help at the expense of burned fingers.

The later bulbs were treated to keep them from going off enmass but most of flash bulbs would go off if they were next to another which went off. In fact, it was an old press photographer's trick to wedge an extra bulb in the reflector when some more light was needed. The bad part was having a pocketful of bulbs go off all together. They would also go off if a radio transmitter was keyed nearby.

I got to like the smell of frying plastic from the bulb coating and the interesting "crunch" when steping on them, not unlike walking on snails after a rain storm ("not on my carpet please")..

I still have a few "glamour" shots of girls I knew in highschool made with a Speed Graphic and bulbs. They were blinded long enough for me to make a get away.

Still, they are the easiest way of obtaining really large amounts of light easily

----
Richard Knoppow
Los Angeles,Ca.
dickburk@ix.netcom.com

From Rollei Mailing List:
Date: Thu, 20 Jan 2000
From: Richard Knoppow dickburk@ix.netcom.com
Subject: Re: [Rollei] Flash Synch

you wrote:

>Just out of curiosity, what types of applications are people finding for
>these bulbs?  Although they are a cheap (in the short term) method of
>obtaining large amounts of power, who really needs that much power?  I have
>heard that cavers use them.  Are there any list members using them on a
>rollei?  Is it simply the novelty appeal?
>
>Shaun
>South Korea
>
>>They still make flash bulbs in Ireland.

The Irish made bulbs are expensive. A little searching will find tons of old bulbs at more reasonable prices.

Flash bulbs have the advantage of power and very light weight. The guide number for a GE #5 bulb, one of the smaller ones, for ISO-100 film at 1/100th sec shutter speed is about 200. The #50, a biggie meant to be used in studio reflectors with open flash has a guide number of 600 for ISO-100 film. The Sylvania (formerly Wabash) Press 40 has a GN of around 360 for ISO-100 at 1/100th sec. Strobe units which can match this are pretty large.

OTOH, having had to use bulbs when there was no other choice I can say they were a PITA. Expensive and a mess. Good flash holders would spit out spent bulbs without having to touch them but sometime they needed help at the expense of burned fingers.

The later bulbs were treated to keep them from going off enmass but most of flash bulbs would go off if they were next to another which went off. In fact, it was an old press photographer's trick to wedge an extra bulb in the reflector when some more light was needed. The bad part was having a pocketful of bulbs go off all together. They would also go off if a radio transmitter was keyed nearby.

I got to like the smell of frying plastic from the bulb coating and the interesting "crunch" when steping on them, not unlike walking on snails after a rain storm ("not on my carpet please")..

I still have a few "glamour" shots of girls I knew in highschool made with a Speed Graphic and bulbs. They were blinded long enough for me to make a get away.

Still, they are the easiest way of obtaining really large amounts of light easily

----
Richard Knoppow
Los Angeles,Ca.
dickburk@ix.netcom.com

From Rollei Mailing List;
Date: Fri, 21 Jan 2000
From: Laurence Cuffe Laurence.Cuffe@ucd.ie
Subject: [Rollei] Off topic: uses for flash bulbs

Other uses beside trains are stately homes i.e. large buildings which are not lit up at night.

On a more tecknical note flash bulbs can be used to get around the maximum shuter speed limitation of focal plane shuters as unlike electronic strobe for the period that they are firing they are a continious light source.

This also would make them usefull with a high speed motor drive as they get round the problem of lash recharge time. Some bulbs can burn for as long as 3 seconds. Finally and related to the above theyre used for much the same reasons for very high speed movie work such as watching the volvo hit the wall, the rocket go by etc.. apparently nasa buy them by the pallet load!

Hope this helps
Larry Cuffe

From Rollei Mailing List:
Date: Fri, 21 Jan 2000
From: Bob Shell bob@bobshell.com
Subject: Re: [Rollei] Flash Synch

That's be Winston Link, the world's finest photographer of trains in my opinion. A great book of his photos came out last year and has him and an assistant on the cover surrounded by bulb flash equipment.

The problem with using massive numbers of flash bulbs as he did was that you only got one shot, and if something wasn't right you were done in for that night. Also, using lots of bulbs like these could be dangerous since static electricity could set them off.

Bob

From Rollei Mailing List:
Date: Fri, 21 Jan 2000
From: "Carl Wegerer, III" colibris@swbell.net
Subject: Re: [Rollei] O Winston Link

Small world. I was visiting Santa Fe, NM yesterday to photograph trains and landscapes. I parked my car in the municipal parking lot and "stumbled" upon the Andrew Smith Gallery across the street (my goals were only to visit the Georgia O'Keeffe Museum and the Museum of Fine Art). It was fate! The gallery had a O. Winston Link photograph in the window, so I just had to go inside. Inside were "Taking Water NW 104", "Horse and Y6 Bridge 425" and my personal favorite, "Hot Shot Eastbound, Iager, WV" (this is the image of the drive-in theater showing the film with the airplane on the screen just as the train passes by). I told John Boland, the associate director, that the timing and subjects of the photograph are truly amazing - cars, planes and trains all in one shot. The price is too, $3,500.

Also inside were "Georgia O'Keeffe" by Karsh and "Pablo Picasso" by Irving Penn. There were two images by Annie Lebovitz: "John Lennon/Yoko Ono" and "Greg Louganis".

I have an old railfan magazine that told the story of how Link did his work and lighting diagrams. This man must have spent a great deal of money on flashbulbs!

Carl Wegerer, III
Mesquite TX

P.S I now need to find all the messages on this subject in my trash folder and read them to see what I missed.

From Rollei Mailing List:
Date: Mon, 01 Nov 1999
From: Richard Knoppow dickburk@ix.netcom.com
Subject: RE: [Rollei] 2.8GX

you wrote:

>All of the cameras that have a "B" on their shutter speed dial.
>That's what it was there for.
>
>Now if your question was which production camera still has "M"
>synch?
>That may be more difficult to answer.
>
>Leonard
>-----

No, the "Bulb" the B stands for is an air bulb. It is simply a setting where the shutter stays open for as long as the tripping lever is pushed. although it can be, and often was, used for "open flash" i.e. non-synchronized flash, that isn't why its there.

Flash bulbs requrire that the bulb be fired a few milliseconds before the shutter is tripped so that the bulb can get going before the exposure is made. Different bulbs required different amounts of delay. Class-M (for Medium delay) bulbs requrire 20 milliseconds to reach their peak after being fired. So shutters made for them had a time delay mechanism built in to provide the delay. Strobe or "X" synch fires the flash at the moment the shutter reaches the fully open point. If its used for flash bulbs at normal shutter speeds the bulb will go off after the shutter has opened and closed again.

There were two other classes of bulbs meant to be used with synchronizers: Class FP, a long-peak bulb for for use with focal plane shutters, and Class-F (for Fast) bulbs which required only a five millisecond delay and could be used with X synch if the sutter speed wasn't too high.

There were also Class S (Slow) bulbs meant to be used with open flash and slow shutter speeds. These bulbs delivered a perfectly enormous amount of light and were intended to be used in standard photo-flookd reflectors.

You now know more about flash bulbs than you probably want to.

......

Richard Knoppow
Los Angeles,Ca.
dickburk@ix.netcom.com

From Panoramic Mailing List:
Date: Wed, 26 Jul 2000
From: Edward Meyers aghalide@panix.com
Subject: Re: Question on Noblex Panorama

One answer about flash was partially true. With conventional flash or flash bulbs the duel-time is too short to produce a proper exposure for the entire frame. But long-duration flashbulbs, which have a duel-time of a few seconds would work if the turning time is within the duel-time. These large flashbulbs were made and sold by Sylvania for use with high-speed cameras which exposed 100 ft. of 35mm film in just a few seconds. I don't know if the bulbs are still manufactured, but I have about 100 of them for future use. Twenty odd years ago I asked a friend at Sylvania to send me a sleeve (10 or 12 bulbs). He made a mistake and sent me a case. Ed

From Speleonics Mailing List:
Date: Tue, 31 Oct 2000
From: Gordon Cole gcole@fred.net
To: speleonics@altadena.net
Subject: Flashbulb Power

I was on a cave photo trip a week ago and we had problems with some of the flashbulb guns that were being used not setting off the bulbs. This caused us to lose a lot of the shots. Our M3B, 5B, and 25B flashbulbs and their flash guns all worked fine. However, my friends 2B and 3B flashbulbs and or flash guns did not always fire. These bulbs are the ones the size of a normal household 100 watt light bulb. We had three flash guns with us for these bulbs and at least two, and maybe all three, failed to fire at least once. Each gun is made the same and consists of a socket epoxied onto a plastic box and wired through a button to a battery holder with 2 new alkaline C cell batteries. After the trip we measured the resistance of a couple of the bulbs that failed to fire and they measured about 1 ohm, the same as a bulb that hadn't been tried. A voltmeter at the flash gun's bulb socket terminals measured 3.1 volts when the button was pushed. When a bulb failed to flash during the trip, replacing it with another usually didn't help as the second bulb usually also failed to fire. One test that we haven't done yet is to make sure there is circuit continuity when the bulbs are screwed in.

My question is, can anyone tell me what voltage we should be using to fire these 2B and 3B flashbulbs? I believe manufacturer's data indicates 3 to 120 volts. If we should be using a higher voltage, can a capacitor/resistor be used in some combination to increase the instantaneous power made available to the bulb when the button is pushed? If three volts is enough, do C cells provide enough current to ignite the bulbs? I wouldn't think it would take much.

Thanks for your help.

Gordon Cole

From Speleonics Mailing List;
Date: Tue, 31 Oct 2000
From: Al Jagnow al-jagnow@uiowa.edu
Cc: speleonics@altadena.net
Subject: Re: Flashbulb Power

Hi Gordon,

OK - 3 volts across 1 ohm = 3 amps = 9 watts It may help to measure the actual current with one of the bulbs that fails to fire. My guess is that you have too much series resistance in your batteries or in the circuit or in the push button. You may want to check the voltage across the bulb socket with a one ohm load connected. I would suspect that it will be a bit less than 3 volts. Take some emery cloth and clean the contacts on the bulbs before putting them into the socket and clean the ends of the batteries and the contacts in the battery box - get that series resistance down. Going to D cells may help. Using a nice heavy duty snap action push button may help. It may also help to put a capacitor in parallel with the batteries. It would also help to use a higher voltage - say 6 or 9 volts.

I have an ancient flash (1940's) that uses two D cells with a 100 mfd capacitor in parallel. It seems to work every time but it is death on flash sync contacts in most cameras so it needs to be fired manually. It has a spring loaded plunger that operates a cable release to open the camera shutter and then closes a contact to fire the flash. I believe that you could reliably fire the 2B and 3B bulbs with two 9 volt transistor radio batteries connected in series (to give 18 volts) with an electrolytic capacitor in parallel to provide the current needed to vaporize the trigger wire.

You should note that many of the smaller flash units for the M3B, 5B and 25B bulbs use a 22 volt battery and a capacitor. Perhaps that would be another approach to try.

You may also want to check (though I'm not sure how) the quality of the 2B and 3B flashbulbs. Many of these are of relatively ancient manufacture. I can see several possibilities for them to lose quality with age and handling.

BTW - the 2B and 3B bulbs fire nicely (though perhaps a bit too violently) with 120 vac as demonstrated in dorm room pranks almost annually.

Al

From Speleonics Mailing List:
Date: Fri, 3 Nov 2000
From: David Gibson david@caves.org.uk
To: speleonics@altadena.net
Subject: Re: Flashbulb Power

In article "Flashbulb Power" in , on Thu, 2 Nov 2000 Richard Rushton richard@yabon.demon.co.uk writes

>You may also be interested in an article that I have published in the
>CREG journal relating to a flashbulb gun. CREGJ 31, March 1998.

Ive done some further work on this circuit (Richard's circuit was based on an earlier circuit of mine, also in the CREG journal). My latest version combines the capacitor discharge bit with one of my slave units and is therefore similar to the Firefly bulb firer. There are several differences though - one of which is an LED to tell you if the unit has fired. This is helpful because you can set up your shot and 'test' that all the slaves are working, without wasting flashbulbs. Im going to be selling kits of parts for this later in the year - Im still dithering, wondering what sort of box to put it in :-) Details are at

http://www.caves.org.uk/flash/

--
David Gibson

From Speleonics Mailing List:
Date: Thu, 2 Nov 2000
From: Richard Rushton richard@yabon.demon.co.uk
Cc: speleonics@altadena.net
Subject: Re: Flashbulb Power

Hello all,

I've been following the discussion on firing big flash bulbs and agree that boosting the voltage is the best solution.

You may also be interested in an article that I have published in the CREG journal relating to a flashbulb gun. CREGJ 31, March 1998. The gun uses a battery to charge a capacitor via a simple circuit that checks the bulb contact resistance. Basically if there is a poor contact then the resistance will be higher than a reference and the capacitor circuit is not turned on. A green LED informs the user that he has a good or bad contact. When the bulb is fired (by slave or camera contact or manual push button) a thyristor is triggered that dumps the current from the capacitor into the flashbulb. This means that the slave, camera or batteries do not see the high current that is used to fire the bulb. It also has the ability to short out the bulb holder contacts to make loading the gun a lot safer - a big bulb going off whilst you are holding it is not to be recommended.

I have used a 9V PP3 battery in this circuit and have had no problems with the bulbs failing to fire once the green LED is on to indicate a good contact. In fact since using this gun I note that bad contact is very common (at least with my bulbs and holder) and I quite often have to jiggle the connections to get a good contact.

The circuit is very simple and should be well within the capabilities of most hobby electronics dabblers.

--
Richard Rushton

From ROllei Mailing List:
Date: Tue, 05 Dec 2000
From: "Arlo T. Dog" ArloTDog@earthlink.net
Subject: Re: [Rollei] OT flash bulbs/ demolition

Also, check out the railroad photography of O. Winston Link, who specialized in lighting moving trains at night with lots of flashbulbs.

Ed K

>   And take a look at "Naked City" by
> WeeGee to see what flashbulb photography can do--stunning!
> JMcFadden

From ROllei Mailing List:
Date: Mon, 04 Dec 2000
From: Richard Knoppow dickburk@ix.netcom.com
Subject: Re: [Rollei] Rolleiflex SL35

you wrote:

>> So "FP" stands for "Focal Plane"? And here I've been using Flash Powder
>(FP)
>> all these years... 8-)
>>
>> Naw, not really.
>>
>> Alex
>=-=-=-=-=-=-=
>
>The old master who gave me my basic grounding in photography way back in the
>Dark Ages told me that FP referred to "Fast Peak" bulbs made for use with
>focal plane shutters. He said that since the focal plane was fully open only
>for an instant and only at slower shutter speeds, it was necessary to get
>all the light on the subject at that instant. I remember using FP rated
>bulbs back then that were filled with a gas instead of the metallic filament
>of Medium Peak or Class M bulbs.
>
>Apparently at the higher shutter speeds the focal plane opening is a mere
>slit that passes rapidly across the film surface, effectively "painting" the
>image on the emulsion a little at a time. The leaf-type shutter remains
>fully open a little longer and a medium peak bulb provides full light for a
>few more milliseconds.
>
>The only thing I know for certain is that clear flashbulbs create a much
>"warmer" light than does electronic flash. Gad it was fun burning those old
>#2 and #22 bulbs in that Speed Graphic flashgun (and, to stay on topic, I
>also enjoyed slitting the plastic anti-shatter film around the base of those
>#5 and #25 bulbs and launching that little ball at people when using my
>friend's Rolleicord!).
>
>Bill, in KC

Class FP bulbs are wire filled lamps for focal plane shutters. Typically they have a peak duration of around 14 milliseconds, enough for 35mm cameras. 4x5 Speed Graphics could be used with FP lamps on with the shutter set for its highest speed, 1/1000 second. The idea is that the lamp has a fairly flat peak lasting long enough for the shutter to travel across the film. 35mm cameas with vertical shutters, like the Contax, could work with standard flash bulbs.

The lamps the old master was thinking of were General Electric type SM or Speed Midget. These were gas filled lamps with a very short flash duration to yield some motion stopping ability with cameras with simple shutters, like box cameras. They had a delay time of 5 millsconds, similar to other Class-F bulbs.

There were two delay times common for flash bulbs: Class-M, 20 milliseconds; Class-F, 5 milliseconds. Class-F lamps can be used with Class-X (strobe) shutters if the shutter speed isn't too high.

Very large bulbs were Class-S (Slow), about 30 ms delay. Usually these were used open flash in studio reflectors but could be used with Class-M synchronizers and slow shutter speeds.

Flash bulbs put out an enormous amount of light. The largest bulbs, GE #50 or Wabash #3 would have a guide number for ISO-100 film of something like 800. Try to get this sort of intensity with a strobe and remember this is with something you can carry in your pocket.

----
Richard Knoppow
Los Angeles,Ca.
dickburk@ix.netcom.com

From Rollei Mailing List;
Date: Tue, 5 Dec 2000
From: Bill Morgan billinkc@planetkc.com
Subject: Re: [Rollei] Way OT!)

'Way back in the 1960s, Life Magazine photographer Larry Burrows wanted to photograph a US Navy vessel in port in Hong Kong, at night.

He assembled a crew and strung wires throughout the ship's rigging with ordinary lamp sockets affixed, then screwed large flashbulbs into those thousands of sockets. I wish I knew the technical details but apparently the ship's crew was able to provide him a good source of DC power.

Larry then took up his vantage point with cameras set to Bulb exposure and all those flashbulbs were fired more or less simultaneously. The result was some of the most dramatic photographs I have ever seen. In the middle of the night that entire large ship was lighted up like daytime while the rest of Hong Kong harbor was wrapped in darkness.

Larry Burrows was a true genius and his untimely death in that misbegotten war is an abomination.

Bill, in KC

...

From Rollei Mailing List;
Date: Tue, 5 Dec 2000
From: JJMcF@aol.com
Subject: Re: [Rollei] OT flash bulbs/ demolition

Based on some experiments with a graphic 4x5 press camera and a Rolleiflex, I strongly recommend trying out flashbulb photography. I don't much like flash of any kind, but when you have no alternative to artificial sun, flashbulbs offer an interesting difference from strobe. The light seems to envelop the subject in a way that strobe doesn't. And take a look at "Naked City" by WeeGee to see what flashbulb photography can do--stunning!

JMcFadden

From Rollei Mailing List;
Date: Tue, 05 Dec 2000
From: Richard Knoppow dickburk@ix.netcom.com
Subject: Re: [Rollei] Way OT!)

you wrote:

>Richard,
>Did those bulbs let you use bounce flash outdoors on cloudy days?.....and did

No but flash powder practically does. The famous Kodak Aero-Ektar lenses were intended for night reconnaissance photography using flash bombs. Flash powder is useful where very large areas must be illuminated. I think O Winston Link used it occasionally and I've seen color pictures of the insides of caves illuminated with it (don't know what they did with the smoke).

>the power of those suckers produce the mindset that causes thousands of
>people with point and shoot cameras to use a flash to take pix from the
>stands at an outdoor trackmeet...at night....300 ft from the action?
>Charlie

Those folks give TV football long shots a nice sort of sparkley effect. Speaking of which I've seen people take pictures of TV screens with flash.

I miss the smell, and crunch under foot of bulbs, two features strobe just can't compete with.

----
Richard Knoppow
Los Angeles,Ca.
dickburk@ix.netcom.com

rec.photo.equipment.medium-format
From: jackjennings@my-deja.com
[1] high sync voltage cure
Date: Tue Dec 12 2000

I recently went to the Paramount site and noticed that they now offer cords with a built in surge protector to reduce the sync voltage. think its a great idea and wanted to share the info.

http://www.paramountcords.com/vp.htm

Jack

Date: Sun, 14 Jan 2001
From: jjs john@stafford.net
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: X-sync, Flash Bulb, What Speed?

I can only speak of M5 and 25 bulbs. I've no idea how little bulbs behave. On X-synch you shouldn't go faster than 1/30th of a second because the flash fires so late that you need the shutter to be open for a long time to get the significant part of the flash's output. However, feel free to experiment. At higher shutter speeds you will find a remarkable drop-off in output, and it won't follow the usual metrics.

And isn't it disappointing that an earlier camera like that would have no M synch?

Date: Sun, 14 Jan 2001
From: "Mike" NEDSNAKE@email.msn.com
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: X-sync, Flash Bulb, What Speed?

How M sync works.

When you release the shutter (any speed) the bulb is ignited a small gear train in the shutter delays the shutter from being fully open until the bulb reaches its peak burn, about 17MS. At that time both the shutter is fully open and the bulb has reached its peak.

d I would guess ( I may be wrong ) that in the case of your shutter the 1/30 or 1/60 has a built in delay to allow for the burn time.

Mike

From Rollei Mailing List:
Date: Thu, 1 Feb 2001
From: Lloyd Schultz Lschultz2@nconnect.net
Subject: [Rollei] O. Winston Link dead at 86

I know that this is not topic specific, but thought members who do not know may be interested. The following came across the wire as a cutline to a fine looking photo:

FILE--Photographer O. Winston Link sits on a steam locomotive in Roanoke, Va., Wednesday, Aug. 2, 2000 while being photographed for Vanity Fair magazine. Link, 86, was found dead in his car Tuesday, Jan. 30 outside a Metro-North train station in Katonah, N.Y. (AP Photo/The Roanoke Times, Josh Meltzer)

Link photographed the demise of steam locomotives in the '50s. Mostly night photos, he used a variety of arrays of flash bulbs with miles of wire in the days before flash slaves. He was an incredible talent.

Lloyd
Lschultz2@nconnect.net

From Rollei Mailing List;
Date: Fri, 02 Feb 2001
From: Bob Shell bob@bobshell.com
Subject: Re: [Rollei] O. Winston Link dead at 86

I live near Roanoke. The local TV stations did a very nice tribute to Link earlier in the week.

There are plans to build a museum in his honor in the old N & W passenger station in Roanoke.

Bob

From Rollei Mailing List;
Date: Fri, 02 Feb 2001
From: David Morris davidrobertmorris@lineone.net
Subject: Re: [Rollei] Bulb flash?

>  Guide numbers for clear bulbs in good reflectors are very high. For
>ISO-100 film and a General Electric #22 (one of the more powerful bulbs)
>the guide number for a shutter speed of 1/100th is around 700. For a
>bayonet base #5 the guide number would be about 320. That's a lot of light.

I used both big and small bulbs for many years in architectural photography and can vouch for them.

The big bulbs (size of an electric light bulb) are like carrying around a large studio light. I used Bowens Boflash lamps which were very light and robust. They have a detachable lightweight aluminium reflector. Several can be linked with effective cord or cordless connectors. They also take Pf1b small bulbs with a plug adapter. I don't know whether this stuff is available outside the UK (or even inside it these days).

BTW, best of all was the Bowens Blaster which fired four of big bulbs simultaneously from a large rectantular reflecter. Felt like a hand grenade going off but great for illuminating large spaces where hand held electronic flash was useless.

I have also used a small Agfa bulb flash unit of the 1950s and 60s where the reflector is made up of "petals" which are rotated out to open and close (sorry don't know the technical jargon) and while I found it unbelevably small and light for its power, I had trouble with hot spots on pictures.

Bulb flash is different to electronic flash, it is much more like real light. It gives a softer more natural feel and and a greater sense of three dimensions. However, it is slow in that you have to set the shutter speed to 1/30 sec or slower for the larger bulbs and 1/60 for the smaller bulbs on focal plane shutters. With leaf shutters and an M setting you can use faster speeds but with a corresponding loss of power for each increase in shutter speed. Another characteristic is that because the flash lasts much longer, human subjects are momentarily blinded by it - great fun for one off shots but not so good for a longer shoot with the same person.

David Morris

David Morris (pbccon@gn.apc.org@gn.apc.org)

From Rollei Mailing List;
Date: Thu, 7 Dec 2000
From: Edward Meyers aghalide@panix.com
Subject: RE: [Rollei] Genuine photography question.....

About shooting flashbulbs with my Rollei... twenty years ago I contacted a friend at Sylvania, the flashbulb people. I asked my friend to send me a sleeve of the "long-peak" bulbs they sold for high-speed picture making on 100ft rolls of 35mm film. This bulb burned for about 2 1/2 or 3 seconds, giving time for an entire high speed sequence to be recorded. I wanted to try the bulbs, which are the size of 100 or 150 Watt conventionals, at night shooting a picture from the Empire State building of Queens or Brooklyn, or just Manhattan. He didn't send a sleeve. He sent a case. Never shot the pictures, but I do have, in my garage, the case of long-peak bulbs...I think about 100 or more of them. Someday I'll shoot the picture. Got the flashgun with a dish reflector to do it with. Norman Rothschild gave me the flashgun about 17 years ago.

Ed

calciua@hn.va.nec.com wrote:

> I have had very good luck with Bergger 200 sheets in 5x7. I shot the film
> at ASA 80 and used a bunch of flashes to illuminate my target (a house).
> You can use the same technique, or just string together a bunch of
> flashbulbs that we discussed earlier on the list. I remember reading
> somewhere that NASA is buying the flashbulbs by the pallet load. I am sure
> a simple call to their procurement department at either Cape Canveral or
> Goddard Space Center will help locate their source. In USA this is public
> information and NASA will give it out freely.
>
> Andrei D. Calciu (VA-4270)

From Rollei Mailing List;
Date: Wed, 01 Aug 2001
From: Richard Knoppow dickburk@ix.netcom.com
Subject: Re: [Rollei] OT Rolleiflash

you wrote:

>Just got a rollei flash.  I have no idea how to work it or what kinda
>flashbulbs it uses.  I have a automat MX.
>
>
>Tks
>
>tim

It takes a 22.5 volt battery. I think they are still made but are expensive. There should also be a small pilot light in it for testing the bulbs. These are 1.5 volt radio lamps. I will have to look to see what type. These bulbs may be hard to find.

The flash will take any bayonet type flash bulbs. The most often used bulb is a General Electric No.5 Or Sylvania Superflash Press-25 which is a Class-M bulb. The synch setting on the camera should be on M.

There is also a No.5B or Press-25B which is the same bulb with a blue filter coating to suit it to daylight color film.

There was also a Class-SM or Speed Midget bulb. This is the same size as the No.5 but has no wire filling. These are gas-filled with very short delay times (5 ms) and should be used on X with slow shutter speeds.

The guide number for a flash bulb varies with the shutter speed since the flash duration is fairly long (except for SM).

For the No.5 and ISO-100 film the guide number at 1/100th second is around 200. That's f/20 at ten feet! At 1/30th second, where the full duration of the flash is used, the guide number becomes about 300. Try matching that with your strobe. :-)

----
Richard Knoppow
Los Angeles,Ca.
dickburk@ix.netcom.com

From Rollei Mailing List;
Date: Wed, 1 Aug 2001
From: Lawrence Ober leo@jove.com
Subject: Re: [Rollei] OT Rolleiflash

You will need an Eveready #412 22.5v battery. They can be ordered online from Radio Shack ($6-7?). The flash was designed for standard bayonet base flashbulbs, i.e. GE #5 or Sylvania Press 25. These are very expensive unless you get lucky. The miniature bayonet base bulbs such as M2 and M3 can be used with an adapter. Two good commercial sources of bulbs are Cole's Camera http://www.colescameras.com/flashbulbs.htm and Cress Photo http://www.flashbulbs.com/Default.htm . Cole's is a bit less expensive. I recently bought some M3 and M3B (the "B" is for blue coated bulbs balanced for daylight color film) bulbs from Cole's at $6 and $8 a dozen, respectively. The full-size bulbs like Press 25 are now going for up to $36/dozen. The M3 puts out just as much light from a smaller package. Remember, flashbulbs have not been in regular production for many years so the prices are steep as they are new old stock. The little base adapters used to cost less than a dollar but are now $10-20. The only item likely to fail would be the capacitor inside the flash. There is a 2.5v flashlight bulb in the unit for testing (you will need a battery and bulb in place. Replacements are easily found at Radio Shack. Any 2.5v screw base miniature lamp will do. I assume the mechanical and electrical connections are self evident.

I can scan a couple instruction pages from the old Amphoto "Rolleiflex Guide" and email it to you.

Larry

Date: Thu, 08 Nov 2001 
To: rollei@mejac.palo-alto.ca.us
From: Richard Knoppow dickburk@ix.netcom.com>
Subject: Re: [Rollei] X or M sync with a magn. powder flash?

you wrote:
>Hello!
>
>Should I use the X or M sync on my cameras if I use a flash with flashpowder 
>(magnesium/potassium permanganate)?
>
>
>Just interesting to know. I did some experiments with magnesium 10-15 years 
>ago. Fun material, but dangerous, especially if you have clothes made of 
>cellulose nitrate soaked in nitro glycerine. :-/
>
>/Patric

  Flash powder was used by opening the shutter, setting off the flash, and
closing the shutter. The burn time will depend on the compounding of the
powder and the amount. Probably also on the powder holder. The powder
manufacturer shold give some data, or are you mixing the stuff yourself? If
so be very careful, its extremely hazardous. 

  Flash synchronizers appeared on the market following the introduction of
flash bulbs around 1931. Large flash bulbs were used open flash as above
but bulbs with controlled burn times were quickly introduced along with
methods of synchronizing the shutter. The first synchronizers were
solenoids to trip the shutter. A solenoid can be designed to have a lag
between the time they are activated and the mechanical action of tripping
the shutter but the system depends on having well controlled burn rates
from the flash bulbs. 

  You could certainly use X synch in combination with a long shutter speed
with powder. You could measure the lag and duration of the flash from the
powder with a photoelectric sensor and a recording osciloscope or similar
instrument. 

  Flash powder is still the single most powerful source of light available. 

----
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com


From: jenspatricdahlen@hotmail.com>
To: rollei@mejac.palo-alto.ca.us
Subject: Re: [Rollei] X or M sync with a magn. powder flash?
Date: Fri, 09 Nov 2001 

>From: Jerry Lehrer You should use open flash, just like the old-time
>photographers did.   Try adding finely divided
>potassium chlorate and ammonium nitrate also.


It's difficult to buy those chemicals here, and they are very sensitive.
Potassium permanganate is easy to buy, and releases a lot of oxygen when
heated. I once tried with potassium nitrate, but it burned with a yellow
color.



The recipe I have goes:

3g potassium permanganate
4g magnesium powder

One gram of the flash powder will burn for 1/5 sec.

Here's another one (in german):

5g magnesium
3g zerinitrat
2g strontiumkarbonat

This one will burn for 4 sec.

/Patric



Date: Tue, 09 Apr 2002 
From: "John A. Lind" jlind@spitfire.net
Subject: Re: [Rollei] Rollei Users list digest V10 #237

 you wrote:
> >From what I can note on my Kodak Master Photoguide calculator, the 5B
> bulb Guide
>No. with 100ASA  and a polished bowl reflector  would be 200. It is based on X
>or F sync at 1/25 sec.
>
>If it is not the large polished flash reflector you would lower the GN to 140.
>
>
>Roger
>
>Stephen J Dunn wrote:


Roger,
Your Guide Number is off by a little . . .

#5B Guide Numbers:
   For X-Sync and leaf or focal plane shutters @ 1/30th or 1/25th:
     4 to5 inch polished bowl: 180, ISO 100, feet.
     Smaller/shallower bowl:  130, ISO 100, feet.
       Note: if

   For M-Sync and leaf shutters ONLY, NOT focal plane:
     1/30th: same as X-Sync GN
     1/60th:  increase exposure by 1/2 stop
     1/125th:  increase exposure by 1 stop
     1/250th:  increase exposure by 2 stops

   #5 (clear):  subtract 2/3 stop exposure

Guide Number Math 101:

f-Stop = (Guide Number) / (Subject Distance)

To convert a Guide Number from one film speed to another:
   (New GN) = {[(New Film Speed)/(Old Film Speed)]^(1/2)} * (Old GN)

To adjust a Guide Number by stops of exposure:
   (a) Pick an aribtrary f-stop number (any one will do)
   (b) Call it "Old f-Stop"
   (c) Add or subtract stops from "Old f-Stop" as desired.
   (d) Call this second one "New f-Stop"
   (e) (New GN) = [(Old GN)/(Old f-Stop)] * (New f-Stop)

-- John



Date: Tue, 09 Apr 2002 
From: Richard Knoppow dickburk@ix.netcom.com
Subject: Re: [Rollei] Rollei Users list digest V10 #237

you wrote:
>Richard,
>
>What type of flash bulb would they use for this P&S; work?
>
>I just got my Graflex three cell flash operational and I just obtained
>several dozen 5 and 5B bulbs.  Its set on my Pacemaker Crown with a
>135mm Xenar.  Would your flash recommendation be a good start?
> Unfortuanately, I don't have an accurate Guide Number for these bulbs
>to determine the proper f/stop.
>
>Steve


  Depends on the era. Pre-war mostly used the larger lamps with medium
screw bases. Post war shifted more to the miniature bayonet base lamps. The
small lamps have nearly as high guide numbers because the reflectors for
them were generally better.

  The Graflite flash gun and its immediate predecessor had reflectors for
both types of lamps. Some other holders used adaptors.

  Midget lamps were mostly the GE No.5 or Wabash/Sylvania Press-25.

  Larger lamps were typically GE No.22 or Wabash/Sylvania Press-40 or
Press-50.

  There were much larger lamps, the size of a 500 Watt photo-flood, for use
in studio reflectors and open flash. The GE No.50 or Wabash/Sylvania No.3
are examples. These were not usually used in flash guns.

 Note that because the light output during the duration of the flash is not
constant that the variation of guide number with shutter speed has no
simple relationhip. Total duration varied with the material with which the
lamps were filled. Post war lamps were mostly filled with a
Magnesium-Aluminum alloy. Very early lamps were filled with aluminum foil.

  Guide numbers vary with the reflector design and shutter speed, but
typical guide numbers are: For film speed of ISO-64 to 100

Shutter speed
1/30th        1/50th         1/100th         1/200th         1/500th

No.5
240             220             180             140             90

No.5B
190             170             140             105             70

GE No.22
320             270             220             160             110

GE No.50 in studio reflector
420



Sylvania lamps have similar guide numbers. Sylvania/Wabash's largest lamp
is the N0.3 Guide number in a studio reflector for ISO-100 and open flash
to 1/30th second = 550.

 There is a little information linked to the Graflex.org web site, but not
full info on lamp characteristics and guide numbers. Usually the sleeves
the lamps came in had charts showing guide numbers for all conditions.

 Blue lamps are balanced for daylight color film.

 Some caution is needed in handling flash bulbs. Especially older ones will
set each other off on contact. In fact, an old press trick was to stick an
extra lamp in the reflector in contact with the regular lamp. The output of
the extra is about half normal. Later lamps were designed not to do this.

Also, flash lamps can be set off by strong RF fields, such as those from a
mobile radio. It occasionally happened that a pocket full of flash lamps
would be set off by friction or by a two-way radio. That can cause severe
burns. The lamps should be kept in the original sleeve if possible since
that will prevent their setting one another off.

  Another type of late bulb was called the Speed Midget. This was a gas
filled lamp (no wire filling) made for box cameras. It has a very short
delay and will work with X synch. These have a total flash duration on the
order of 1/200th giving some motion stopping ability to cameras with slow
shutters.

  Note that both the No.5 and screw base lamps are Class-M requiring a 20
millisecond delay. Solenoid synchronizers were designed for this type of
lamp and self synchronizing shutters should be used in the M postion. Some
miniature lamps were designed for 5 millisecond delay (Class-F) and should
be used only with self-synchronizing shutters set for F.

 There were also special long-duration bulbs made for use with focal plane
shutters. The 4x5 Speed Graphic will work with these only at the top speed
since the shutter curtain total travel time is too long at other speeds.

  Flash bulbs have tremendous ouput for their size and weight but were
never cheap.
----
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com



Date: Tue, 09 Apr 2002 
From: Richard Knoppow dickburk@ix.netcom.com
Subject: Re: [Rollei] Rollei Users list digest V10 #237

you wrote:
>From what I can note on my Kodak Master Photoguide calculator, the 5B bulb Guide
>No. with 100ASA  and a polished bowl reflector  would be 200. It is based on X
>or F sync at 1/25 sec.
>
>If it is not the large polished flash reflector you would lower the GN to 140.
>Roger

 Please note that the No.5 is a Class-M bulb intended for use with a 20
millisecond delay. If used with X (no delay) or F (5 millisecond) synch it
must be used with slow shutter speeds or the shutter will open and close
before the bulb has started to burn. Peak output occurs 20ms after the bulb
is energized.

 Speed Midget lamps (without wire filling) are Class-F and can also be used
on X synch with fairly slow shutter speeds.

 No.5 and Speed Midget lamps are suitable for use in Rollei type flash
guns.
----
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com



Date: Tue, 16 Apr 2002 
From: Jerry Lehrer jerryleh@pacbell.net
To: rollei@mejac.palo-alto.ca.us
Subject: Re: [Rollei] OT: Flash Bulb Help -- Thanks

Les

You can do better than that Les.  We old timers know that there were
F, M, and FP bulbs, but older-timers know 'bout the slow M bulbs (called
SM bulbs?).

Jerry Lehrer


From rollei mailing list:
Date: Tue, 16 Apr 2002 
From: Richard Knoppow dickburk@ix.netcom.com
Subject: Re: [Rollei] OT: Flash Bulb Help -- Thanks

you wrote:
>Thanks to all who contributed regarding the Guide number issue relating
>to 5B and 5 bulbs.  I hope to try this weekend.
>
>I understand the GN depends on the size of the reflector (5 1/2 inch or
>7 inch).  I recently obtained a 7 inch reflector to supplement the 5 1/2
>inch one I have, and note it is  designed for larger screw base bulbs.
> I also see it has a means to adjust the positioning of the reflector.
> Was this to adjust the "focus" of the light output?  How was that done
>or was it something never bothered with?
>
>I also note on my Graphex bi-post shutter (marked as a Full Synchromatic
>made by Wollensack, f/ 6.8 - 32 for my 90mm lens) the following
>artificial light settings:  setting one--M (black letter), setting two
>-- M (red letter), setting three -- F (red letter) and X (black letter)
>and setting four -- off.  I can figure out "off" and "X"  But why the
>two different colored M settings?
>
>
>Thanks again,
>
>Steve Dunn

 The large reflector has a vertical adjustment to allow adjusting for
different sized bulbs. There are at least three envolope sizes used for
medium screw base flash lamps. The reflector should be centered on the
lamp. Put a lamp in the reflector and look at it from about 15 feet away to
check the centering.

  The smaller reflector is for miniature bayonet base lamps, which are
standardized in size. The Graflex reflector has an adjustment for angle of
coverage. The Normal position results in about a 60 degree beam. Moving it
back narrows the beam a little for use at a distance or with longer focal
length lenses. The narrow position is actually about the same as the larger
reflector. The smaller reflector and miniature lamps produce somewhat more
even lighting than the larger reflector and lamps.

  The synchronizer on the Wollensak shutter (also Ilex) allow changing the
delay time so that more of the lamp output is available at slower speeds.
For Class-M lamps the peak output occurs 20 milliseconds after ignition.
Normally, the synchronizer is set up so that the peak output occurs exactly
as the shutter reaches maximum opening for its highest speed. Since opening
time is about the same at all speeds some of the lamp output at the
beginning of the flash may be lost when using lower speeds. The Wollensak
shutter has two delay times for Class-M bulbs, one, about 20 ms for slower
speeds (white) and one for a longer delay, around 25ms to 30ms, for use at
slower speeds. This M is in red to be used with the shutter speeds marked
in red.

 Wollensak shutters do not have a seperate setting for Class-F (fast, 5 ms)
lamps as does the Kodak Flash Supermatic. The F-X setting can be used at
slower shutter speeds as marked in Red on the speed dial.

 The only Class-F bulbs made were the gas-filled Speed Midget bulbs made by
General Electric. These were intended mainly for use on box cameras where
the very short flash duration gave some motion stopping effect and a simple
contact was enough for "synchronization". The effective "shutter speed" is
around 1/200th.

  The "Off" position is to allow opening the lens for focusing without
setting off the flash, or simply to turn off the flash where you don't need
it but want to have a bulb ready.

  Kodak Flash Supermatics have two sets of contacts, one for Class-M and
Class-F, and another for Class-X (strobe). The delay for the Class-M and F
contacts must be cocked separately after cocking the shutter, the Class-X
contacts are always in circuit but have a 5,000 ohm resistor in series so
they won't pass enough current to set off a flash bulb. The delay mechanism
is not cocked to use Class-X synch and the setting of the M-F slider has no
effect. The blade arrestor in Kodak synch shutters holds the blade ring
from moving to the completely open position to avoid actuating the X-synch
contacts during focusing. For bulbs the shutter is focused first and the
delay cocked afterward.
----
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com


From rollei mailing list:
Date: Tue, 16 Apr 2002 
From: Richard Knoppow dickburk@ix.netcom.com
Subject: Re: [Rollei] OT: Flash Bulb Help -- Thanks

you wrote:
>Thanks to all who contributed regarding the Guide number issue relating
>to 5B and 5 bulbs.  I hope to try this weekend.

  A brief addendum. Special flash bulbs were also made for focal plane
shutters. These are called Class-FP. They have a very long duration of
reasonably constant output. The shutter speeds they can be used with depend
on the shutter travel time, which must be within the duration of the flash.
Most 35mm cameras can be used at all speeds since nearly all of their
shutters have constant travel time. (Not sure of the old style Contax
shutter). For Speed Graphic and Graflex cameras the speeds are more limited
since the travel time depends on the overall tension and that in turn
depends on both shutter tension and slit width settings. For 4x5 cameras
only 1/1000 second is useable since the travel time is shortest there.
Smaller format Graphics and Graflexes can be used at slower speeds. Those
with built in synchronizers generally have some color coding showing which
speeds can be used.

  I am mentioning this since Class-FP lamps may be practical for use with
Rolleiflex SLR cameras. The speeds which a focal plane shutter can be use
with strobe are limited to those where the sllit opens the entire gate
area. This is limited so rather slow speeds on most FP cameras, around
1/60th second on older 35mm cameras and twice or more that on newer ones
which have much faster travel time. I am not sure what the travel time is
for Rolleiflex SLR's but its very probably fast enough to allow the use of
FP bulbs at any speed. This would allow flash fill in daylight situations
where the shutter speed does not allow the use of strobe.
(Plus gets it on topic again).
----
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com



From rollei mailing list:
Date: Tue, 16 Apr 2002 
From: Richard Knoppow dickburk@ix.netcom.com
Subject: Re: [Rollei] OT: Flash Bulb Help -- Thanks

you wrote:
>Richard
>
>Richard, old boy, in both of your responses you neglected to refer
>to those big-assed, foil-filled bulbs like the #50, that had a 30 m-s
>time to peak.
>
>You youngsters should study your photo history :-)
>
>I do believe that the classic railroad photographer, referred to a while
>back, used dozens of those big-assed bulbs in his night photos of
>locomotives on interesting portions of track.
>BTW, I have a manual on that "Woolensock" shutter.  They were just
>as good as their lenses---merely adequate.
>
>Jerry Lehrer


 Those big bulbs, I think the Wabash-Sylvania #3 and GE #50 were the
largest, were usually used in large studio reflectors and exposed open
flash rather than with synchronizers. They produce an enormous amount of
light. A #3 or General Electric #50 bulb has a guide number of around 680
for ISO-100 film. The delay is 28ms to 30ms, usable with Class-M shutters
at slower speeds.

 I disagree about Wollensak shutters, they were very good, better for the
most part than the Ilex equivalents. Wollensak lenses vary all over the
place. They were capable of making excellent lenses but made a lot of junk.
At least in the case of the Enlarging Raptar and the 135mm F/4.5
Raptar/Optar, as found on Speed Graphics, there seems to be something wrong
with the design. The enlarging lenses are awful. The camera lens has
excessive coma. Its quite sharp in the center of the image even wide open
but the coma doesn't go away until its stopped down bast f/22. For
comparison a Zeiss Tessar or Kodak Ektar needs to stopped down to only
about f/8 for the coma to be substantially gone. Other Wollensak lenses I
have or have used are far better than these guys. OTOH, Kodak never made
any junk lenses, even their cheapest ones are good of their type.

  Kodak shutters are very rugged. Internally, they look crude compared to a
Compur shutter but nothing wears out and they are accurate and consistent.
Generally, a good cleaning will bring the speeds back to standard although
sometimes the springs are a little weak. Kodak was concerned with color
photography and made sure their own shutters were accurate ones. Why they
chose to use Ilex shutters on their largest lenses is beyond me. Perhaps
just to keep Ilex in business to avoid anti-trust actions. Kodak Ilex
shutters are not quite the same as the standard Ilex product, different
threading and some other changes.
----
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com



From rollei mailing list:
Date: Wed, 17 Apr 2002 
From: Laurence Cuffe Laurence.Cuffe@ucd.ie
Subject: Re: [Rollei] OT: Flash Bulb Help -- Thanks

>>Richard, old boy, in both of your responses you neglected to refer
>>to those big-assed, foil-filled bulbs like the #50, that had a 30 m-s
>>time to peak.
>>Richard Knoppow wrote:
> Those big bulbs, I think the Wabash-Sylvania #3 and GE #50 were the
>largest, were usually used in large studio reflectors and exposed open
>flash rather than with synchronizers. They produce an enormous amount of
>light. A #3 or General Electric #50 bulb has a guide number of around 680
>for ISO-100 film. The delay is 28ms to 30ms, usable with Class-M shutters
>at slower speeds.

I note from their web site that the meggaflash PF300 has a delay of
about 25ms and a Guide number of 550 for iso 100 film. see:

http://www.meggaflash.com/light%20output%20graph%20for%20pf300%20flashbulbs.htm

again the line may need to be stuck together.
its also worth looking at the specs for the PF330 bulb which gives
an Average of 60,000 lumens for 1.75 seconds.

All the best
Larry Cuffe


From rollei mailing list:
Date: Tue, 05 Dec 2000 
From: Richard Knoppow dickburk@ix.netcom.com
Subject: Re: [Rollei] OT flash bulbs/ demolition

you wrote:
>JJMcF@aol.com wrote:
>
>I need to get a flash gun for my Speed Graphic.
>
>I think all the flashbulbs are being made in Ireland now!
>
>Hope they keep making them!
>
>mark rabiner

  There is still a plentiful supply of old bulbs available used for a lot
less than the Irish outfit wants. I am not sure their prices are really out
of line when the prices of sixty years ago are adjusted for current money
value, but the are a little dear for routine use. c.1940 prices were around
13 to 20 cents per bulb (General Electric) for the sort used in routine
press work.

  Flash guns are around. The best of them were the late Graflite (made by
Graflex) and Heiland. The slightly earlier Graflex guns are the ones being
eaten up by children of all ages wanting laser sabers. Please stamp out any
such vermin you encounter.

  Solenoids are easy to adjust with an oscilloscope and are quite reliable
although a shutter with built-in synchronizer is better. I will explain how
to do this via private e-mail for anyone interested.

  A lot of Rolleis made before synch shutters were modified to take a flash
solenoid, usually disfiguring them. Both Heiland and Graflex made
synchronizers with brackets to fit Rolleis, and there were other
manufacturers. The Graflex solenoid is the most reliable of the bunch.

  There were always problems when using a solenoid, they drew a fair amount
of current so that, if the batteries were not absolutely fresh, the bulb
might not fire, or it fired but the solenoid never tripped the shutter.
Special high-voltage batteries were available for use in flash guns and
Graflex, at least, offered an extension so you could run four batteries
insuring enough current.

  The BC Rollei flash gun for use on synchronized shutters, has none of
these problems. The high voltage batteries used in them may be hard to find
although I believe they are still made.

  Flash bulbs were supplanted by Strobe because Strobe was more practical
for many uses, but flash bulbs are still hard to beat when one wants _lots_
of light.

----
Richard Knoppow
Los Angeles,Ca.
dickburk@ix.netcom.com


From rollei mailing list:
Date: Thu, 22 Aug 2002 
From: Gene Johnson genej2@cox.net
Subject: Re: [Rollei] Flashbulbs

I should have said "for big light with real portability".  I could bring an
800 watt/second monolight, try to find somewhere to plug it in, etc.  but
the 2 dozen bulbs and flashgun weigh a LOT less.  A 283 will do most of the
shots, but where I need to stop down a little or where I need a little
distance, the 25's are amazing.  This is a fairly recent discovery for me,
but a really nice one.  Flashbulbs are COOL.

Gene


From rollei mailing list:
Date: Wed, 28 Aug 2002 
From: Richard Knoppow dickburk@ix.netcom.com
Subject: Re: [Rollei] Flash question

 Mslatfly@aol.com wrote:

> All this talk about flash bulbs has me wanting
> to give them a try again.  The
> only ones I've ever used before are the old
> PR-1 bulbs from my Kodak Brownie
> days.
>
> What I have now is an old flash unit,
> non-Rollei, with no manual.  I'm not
> sure who made it.  The flash is a small unit,
 marked "HR" inside a circle
> (that's not Honeywell, is it?).  The only
> numbers I can find are inside the
> head in the casting, C-17C-1.  I know this was
> a well known brand back in the
> day, but I don't remember who this is, and
> therefore haven't found any info
> on it.
>
> The flash has a five inch reflector, bayonet
> mounted to the flash head.  The
> head has a six finger, evenly spaced, lamp
> holder, with a spring loaded
> ejector button (red) on the back. The stem (or
> handle) is plastic or
> bakelite, hollow, and contains a battery
> (Eveready 505 Photoflash B-C
> Battery), and capacitor.  The stem has a
> threaded hole at the bottom, with a
> cold accessory shoe with locking ring.  The
> connectors are the "household"
> type (double prong).  There are two of these,
> one marked "S," the other
> marked "E."  I have two cords that fit this
> flash, one Rollei connector, and
> one common connector.  Both are also marked
> with the HR logo.  There is no
> corrosion anyplace.  Anyone have any info on
> this?
>

  HR is Heiland Research. Most press photographers used either Heiland or
Graflex flashguns.

The connector marked S is for a solenoid synchronizer. E is for an extension
flash.

  There should be a thrird conncetor for use with a synch shutter unless the
flashgun is very old.

  The socket is for small size flashbulbs like the GE #5. These date from the
late 1930's and were often used in preference to the larger bulbs with
househould type screw bases.

  There should be a push button on the battery case for tripping the flash.
This fires the bulb and also sends a pulse out of the S socket for actuating
the synchronizing solenoid. Usually, the extension connector is in parallel
with the S connector but you can tell by measuring what is there with a
voltmeter.

  Late HR flashguns have interchangible heads for large and small bulbs and
also have a socket for use with synch shutters.


Richard Knoppow
dickburk@ix.netcom.com
Los Angeles, CA, USA


From rollei mailing list:
Date: Tue, 20 Aug 2002 
From: Richard Knoppow dickburk@ix.netcom.com
Subject: Re: [Rollei] Old Photo Flood Lamps #2

you wrote:
>I've begun using flash bulbs with my Graphic 4x5 and Rollei.  I recently
>came across several white and blue Photo Flood lamps, Mazda based, #2.
> These are designed for light stands in a studio setting.  My question
>is whether using such lamps provides that certain flash bulb result vs
>the electronic flash or is this just a primative studio lamp?
>
>Steve

  Photo Flood lamps are marked as such on the lamp. The plain ones have a
color temperatrure of 3400K, the blue ones approximately 5500K,
approximating direct sunlight.

  The characteristic quality of flash is due mostly to the size and
location of the flash reflectors used. For most press work the flash was
fixed to the side of the camera. This has a very identifiable look because
of the close similarity of all the equipment used in press photography in
the old days. When flash bulbs are used off the camera, or in multiple
light set-ups, its quality is the same as for photo-floods or other lights
in the same position.

  N0.2 Photoflood lamps are standard incandescent lamps which are run
overvoltage to increase their output and color temperature. The trade off
is lamp life, wich is no more than about six hours. The draw is 500 watts
but they are considerably brighter than, say, an industrial 500 watt lamp.
They are still made and used: Calumet carries both General Electric and a
house brand.

  The quality of light from a photoflood depends entirely on the lighting
instrument its used in.

  Clear flash bulbs have a color temperature of around 4000K, blue bulbs of
around 6000K.

  A No.2 _flash bulb_ would be a Wabash or Sylvania Superflash lamp.
General Electric, the other major flash bulb manufacturer did not use the
same nomenclature for its lamps. The No.2 Wabash was the equivalent of the
GE N0.22, a standard lamp for use in large press reflectors.

  Both companies made larger lamps, for instance, the GE No.50 and the
Wabash NO.3. Both were designed to be used in standard studio reflectors
and have too long a lag time for use with flash synchronizers. Their light
output is immense. The Wabash No.3, the largest of them all, has a guide
number of around 580 for open flash with ISO-100 film. The guide number
depending on reflector size and type.

  Flash bulbs were introduced about 1931 by Wabash. The first ones were
filled with crumpled aluminum foil. about the late 1930's the foil was
replaced with fine wire made of aluminum or of an aluminum-magnesium alloy.
The bulbs have a fine filiment coated with an explosive mixture which
serves to ignite the foil or wire. After WW-2 some attention was paid to
making bulbs which would not be so easily set off by exposure to strong
radio signals or by a nearby bulb going off. BTW, standard press practice
was to stick another bulb in the reflector for more light. The second bulb
would be set off by the heat from the first one. Light output is only about
half that gotten when triggered the regular way but it was a useful trick.
Sometimes whole pocketsful or boxes of loose bulbs would go off at once. In
a pocket this could cause really serious burns.

----
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com



From rollei mailing list:
Date: Tue, 20 Aug 2002 
From: Craig Zeni clzeni@mindspring.com
Subject: Re: [Rollei] Old Photo Flood Lamps #2

 you wrote: 
schnipps
>   Both companies made larger lamps, for instance, the GE No.50 and the
>Wabash NO.3. Both were designed to be used in standard studio reflectors
>and have too long a lag time for use with flash synchronizers. Their light
>output is immense. The Wabash No.3, the largest of them all, has a guide
>number of around 580 for open flash with ISO-100 film. The guide number
>depending on reflector size and type.

The No. 3 bulb is the type that O Winston Link used in many of his
spectacular outdoor shots...common name in the railfan photo community was
the Tactical Thermonuclear Flashbulb...

Craig Zeni - REPLY TO -- clzeni at mindspring dot com
http://www.trainweb.org/zeniphotos/zenihome.html
http://www.mindspring.com/~clzeni/index.html


From rollei mailing list:
Date: Wed, 21 Aug 2002 
From: Richard Knoppow dickburk@ix.netcom.com
Subject: Re: [Rollei] Old Photo Flood Lamps #2

 you wrote:
>Well actually this is what I obtained on E Bay:
>
>Monster flash bulbs:  10 GE #50 Photo Flash Lamps (blue and clear) Class S
(slow Peak). They closely approximate the size of a 100 watt light bulb.
My internet research indicates the Guide for the bulb with 100 ASA/feet, M
sync, medium sized studio reflector (probably equates to the 7 inch
reflector) and a shutter speed of 1/30th or slower is 420 for the clearor
340 for the 50B!!  With 160 ASA film its rated at 600 or 480 for the 50B.
Did people need eye care after having their picture shot?)
>
>Monster flash bulbs:  4 Wabash #2 Photo Flash Lamps (clear) and without
any information (from the sleeves or the internet) regarding the exposure
guide numbers.  They appear to be the same size as the 50 flash lamps.
>
>6 GE Photo Flood lamps, #2.  All are Mazda based.  The sleeve indicates
that at 8 feet with a high speed film of 40-64 ASA and an f/stop of 8 it
required an exposure of 1/25th second.  This equates to a guide of 64.  The
Photo Flood lamps are indeed studio lamps with a stated life of
approximately 6 hours.  I don't know if there's any practical use for such
studio lamps, given the availability of much more efficient units.  Any
opinions?
>
>
>Steve


  Photofloods were useful when lots of light was needed from relatively
simple equipment which would not overload household circuits.

  There were three sizes in general use: No.1 (250 watts), No.2 (500 watts)
No.4 (1000 watts). No.4 lamps had mogul bases and were meant for large
studio lamps. I've never seen a No.3 lamp listed.

  Photoflood lamps are still useful when one wants to work with hot lights
instead of strobe.

  Large flash bulbs put out considerably more light than a photoflood lamp.
They were not intended for use on the camera but rather in studio lamps.
Such flash bulbs could be used to photograph large rooms or sets with
completely portable equipment. They have rather long duration so were most
often used open flash.

  The most common bulbs for press work were the GE No.22 or the Wabash
Press-50, pretty much identical. Both lamps allowd the use of fast shutter
speeds and small stops. Many press shots were made without focusing: the
camera was set for 15 feet and f/32 and just pointed. Most press shutters
had top speeds of 1/200 or 1/400th, enough to stop some motion bluring.

 Smaller bulbs, like the GE No.5, became available in the early 1940's.
They had less output than the big bulbs but the reflectors designed for
them were more efficient so light output was sufficient for much work,
especially because faster films became available at about the same time.
They were cheaper and easier to handle than the larger bulbs.

  One occasionally sees a picture of a press rig with as many as four
reflectors on it. Even with Press-50 bulbs this would be capable of
lighting up a whole street.

 Strobe pretty much replaced flash bulbs but as the cost of greater weight
and less light output. Flash bulbs remain supreme in terms of simple, light
weight means to obtaining very large quantities of controllable light. I
say "controllable" because flash powder remains the unsurpassed means of
obtaining sheer volume of light.

----
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com


From rollei mailing list:
Date: Thu, 29 Aug 2002 
From: Richard Knoppow dickburk@ix.netcom.com
Subject: Re: [Rollei] Flash question

you wrote:
>Thanks for the info Richard.
>
>The flash has only the two connectors.  None hidden anyplace.  I've had the
>whole thing apart, and their is no solenoid in it, unless the part I thought
>was a capacitor is actually a solenoid?  The device has a part number 75C-5,
>with a 7 in a circle under that.  Also a row of plus signs at the connector
>end.  It has an ink stamp 8-53 which I guess is date of manufacture.  The
>only button on the flash unit is the ejector button.  The flash is 5 3/4
>inches tall including the shoe, without the reflector.  It is 1 3/8 inch
>diameter at the widest point.  My biggest question was, what size bulbs to
>use?  You said GE #5.  Aren't these bayonet base bulbs?  The slots in the
>holder are all the same size, and don't appear to have any wear marks.  Is
>this correct?
>
>Also, I should mention that I got it on ebay.  It came attached to an Agfa
>Isolette I, that I paid very little for.  The flash was connected to the S
>terminal, and to the only connector on the shutter (which operates fine with
>an electronic flash at 1/25).  It was in great shape by the way. Except for a
>frozen focus on the lens, and some very minor corrosion in the exposed metal
>parts.  The shutter, bellows, etc., are near perfect.  It works great now.
>It has an Agfa Agnar lens (1:4.5f, 85 mm with front element focus), and a
>Vario shutter.
>
>Mike Slatkin

 Flash solenoides were mostly mounted on the lens board or front of the
camera. If the flashgun does not have a tripping button it was not meant
for use with a solenoid.

  I am confused by the description of the flash socket. I thought from your
first post that it was for bayonet type bulbs, evidently not.

  Probably this gun was meant to be used with shutters with built in
synchronizers. The S connector goes to the Shutter synch contact, as
before, the E is probably for an extension flash.

  There were a varity of small flash bulbs which became available after
WW-2. Some without a base. The most common were AG-1, all glass bulbs, and
the miniature M2 and M3 "pinless" type bulbs. I actually have some of these
guys stashed somewhere but can't find them at the moment.

  I indulged myself in a new computer today (this is still the old one) so
am a little distracted.

----
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com



from leica mailing list:
Date: Sat, 21 Dec 2002 
From: "Jacques Bilinski & Barbara Bradbury" jbilin@axionet.com
Subject: Re: [Leica] Flashbulbs

Hskan Dennersten at hd@hd.pp.se wrote:
>
> Can you still buy oldstyle flashbulbs somewhere ?
>

They are not cheap anymore but are still available. Checkout:

http://www.dhios.demon.co.uk/Flashbulbs/
http://www.flashbulbs.com/index.shtml



Date: Wed, 25 Dec 2002 
From: "Ganter, John H" jganter@sandia.gov
To: "'speleonics@altadena.net'" speleonics@altadena.net
Subject: [Speleonics] The MegaStrobe Project, and the Ikelite SubStrobe 20 0
(RE: Flashgun Master Unit)

Over a decade ago, there was an project in the US, incited by Bill Storage,
to build an M3B-equivalent cave strobe. My recollections...

The effort got a boost when Storage was able to wrangle a small lot of
extraordinarily high density capacitors from a major Japanese supplier (1600
uF in a small package). Bill Farr designed and built a high-efficiency  
board, which he documented verbally into my tape recorder on a Sistema Cheve
expedition. I built a prototype in PVC in 1991, with a custom-made Pyrex
dome in a carbide lamp reflector. The unit was somewhat large (~5x8 inches,
with a separate battery pack), but approximated an M3B.

Around 1992, Ron Simmons built his own unit using the caps and a board of
his design. Bill Stone also did some work around this time.

Around 1996, I donated my prototype, capacitors, tubes, etc. to Nevin W.
Davis (http://www.nevtek.com/) for further R&D.; Working with Simmons, Nevin
completely redesigned the Farr circuit and built another prototype. Simmons
was assured by the same Japanese mfr that they would NEVER build small 1600
uF caps again in quantity < 100,000 (if I recall correctly).

Nevin's performance testing suggested the output of an M3B. Of course, this
is a complicated business involving optics and reflector. Since Nevin's
packaging used a trough-type reflector, it did not produce the wide angle of
bulbs so desirable for aesthetic passage illumination.

A similar effort was my "TU-83" (http://131.161.254.45/jg/c/tech/), but at a
much lower power.

In 2000, I was looking for an M3B substitute that I could use for fast,
shoot-and-run photography under difficult conditions. I revisited the quest
for the MegaStrobe, and assembled a large PDF file of correspondence,
sketches, notes, etc. from the previous decade of intermittent work.

I decided that the Ikelite SubStrobe 200 was close enough to what I was
looking for, and bought one on eBay for about US$400.

http://www.ikelite.com/web_pages/substrobe_200.html

Output: 200 watt-seconds (somewhere around an M3B depending on who you talk to)
Weight: 3.9 pounds
Size:   4.5x7.5" cylindrical (~125 in3)
Angle:  100 degrees

The SubStrobe is a fine product, and I doubt that cavers will be able to
make something competitive anytime soon. We simply don't have the capital
for R&D; and mfr'ing. (Also, the Ni-Cads they use are very high capacity. I
don't recall the details, but I was never able to find a source for these
genuinely "industrial-grade" and carefully-matched NiCads.)

I used the SS200 in a variety of caving conditions, including alpine
whitewater where it was very nice to not have to load bulbs while shivering
violently.

However, the weight and volume began to get to me. I told myself the SS200
was (really) small and light. But it (really) took up a lot of space in my
notoriously gigantic and overloaded tackle bag.  
After doing a cost-benefit analysis, I decided my inventory of bulbs was
adequate. I built a new series of cave-resistant (o-ring sealed) bulb guns
with embedded Firefly slaves (using enclosures like the "Ruggedized Trigger
Strobe" on the website above). I sold the SS200 on eBay for about what I
paid for it.

I'd recommend that anyone considering a high-power cave strobe take a look
at the SubStrobe 200. It is a nice piece of engineering, and it appears to
be very close to the limits of current technology (battery and capacitor
energy density *and* peak output current). Lithium batteries could reduce
weight (and add cost). And you can always reduce other gear, lift weights,
and/or use more sherpas.

--John Ganter 



From: Willem-Jan Markerink [w.j.markerink@a1.nl]
To: panorama-l@sci.monash.edu.au
Subject: Re: immersive light
Sent: Fri 2/21/2003 


I  recently came across a site with monster-size bulbs....

http://www.darklightimagery.net/bulbcompare.html

http://www.meggaflash.com/

I doubt you can beat these single-use bulbs....

Not sure what gain a stroboscope would bring....those are pretty
powerful too....
-- 
Bye,

Willem-Jan Markerink

w.j.markerink@a1.nl
[note: 'a-one' & 'en-el'!]


From: "Q.G. de Bakker" qnu@worldonline.nl
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: FP flashbulbs - what sync required?
Date: Thu, 12 Jun 2003 

steven.sawyer@banet.net wrote:
> I hate to beat a dead horse, but on a Kiev 60, modified to 645 (by Arax,
> Hartblei or others) won't their be a slight delay from the activation of the
> flash and the clearance of the first shutter curtain across the 645 opening?
> Could this delay be adequate to create an "M" sync? Please leave aside the fact
> that the flash won't fire unless the camera is set to 1/30.

Fastest synch speed of 1/30 suggests that it takes the curtain about that
much time to fully clear the film.

Using M-type bulbs with X-synch, the shutter has to remain open for the time
it takes the bulb to reach maximum intensity (about 25 ms), plus at least
the time until the output has reached half-peak output value (about 15 ms),
in all about 40 ms.

So i think M-bulbs will work using X-synch at speeds of 1/15.

Some cameras from way back when had an adjustable bulb-synch delay to
accomodate different types of bulbs.


Date: Wed, 25 Jun 2003 
From: Gordon Moat moat@attglobal.net
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: ultra cheap polaroid test camera tip Re: polaroid & Max HQ

Bob Monaghan wrote:
> yes, see the paramount cords pages, they have some info;
> http://www.paramountcords.com/

Thanks Bob, got it bookmarked now.

> Older Modern Photo issues had articles on older style LF and pro photo
> cords, but mostly highlight the number of odd ball ones out there ;-)
>
> most camera repairers can move the contacts in the shutter so as to
> convert from M or FP synch flashbulbs to X synch (instantaneous) easily
> enough, though at a modest fee. It is worth trying the connector anyway,
> since some camera lenses work on xsynch (at least at some speeds).
>
> re: flashbulb to strobe adapter
> A simple alternative, if you like electronics, is to build a 15-20
> millisecond delay circuit around a timer chip (CMOS NE555 or similar)
> and use it to trigger the strobe after the needed 20 msec. delay. You can
> use an SCR to trigger the strobe if it is a high voltage type (older
> vivitar 283..). Use a Triac if you want to ignore polarity of flash leads

Actually, not a bad idea. It might be a nice item for some other of my older
cameras as well.

> a related concept is the tail flash (trailing curtain flash) delay
> circuit, see ftp://vmsftp.rit.edu/pub/ritphoto/photoforum/faq-18
> in fact, you should be able to use the flashbulb to strobe adapter
> in this way too, simply use a variable resistor (potentiometer) to
> set the timings ;-) You can also use it to finely tune flashes of repeated
> phenomena such as falling droplets of ink or milk etc. ;-)

Unfortunately, that link would not come up . . . not sure what is going on
with that. The potentiometer might be simpler than the timer chip. See what
you did now Bob, got me started on another project. ;-P

Thanks again Bob,

Ciao!
Gordon Moat
Alliance Graphique Studio
http://www.allgstudio.com


From: Peter Irwin pirwin@ktb.net
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: FP flashbulbs - what sync required?
Date: Sat, 7 Jun 2003 

steven.sawyer@banet.net wrote:
> I'm still trying to figure out a way of beating the flash sync problem
> with the Kiev models (i.e. 1/30 sync). I've done a little research and
> I've run across a solution from yesteryear - the FP flashbulb. However
> I believe that these bulbs required a special FP sync or at least a "M"
> sync.

A focal plane shutter with FP sync will close the flash contacts
at least 16ms before the first shutter cutain begins to uncover
the film. X sync closes the flash contacts when the first curtain
has reached the end of the film gate.

> Then I read another book that says you could use them with an "X"
> sync depending on the speed (I figure that means 1/30 which defeats the
> purpose).

It is worse than that, more like 1/15s. The shutter must remain
open long enough for the bulb to reach peak output. Given the
scarcity of FP bulbs (such as #6 bulbs) this seems wasteful.
You can do the same thing with M class bulbs.

Some cameras with focal plane shutters have arrangements to
use M class bulbs at sync speed by firing the flash about
18 ms before the first curtain reaches the end of the film
gate. You can even get away with double the sync speed with
this arrangement, but trying it any faster will give uneven
exposures.

Peter.
--
pirwin@ktb.net


From: pirwin@ktb.net (Peter Irwin)
Newsgroups: rec.photo.equipment.medium-format
Subject: Re: FP flashbulbs - what sync required?
Date: 7 Jun 2003 

steven.sawyer@banet.net wrote 
> Peter Irwin wrote:
>
> > Some cameras with focal plane shutters have arrangements to
> > use M class bulbs at sync speed by firing the flash about
> > 18 ms before the first curtain reaches the end of the film
> > gate.
>
> But none made today right? Is there a difference between "FP" sync
> and "M" sync?

The Pentax 67 had FP sync in the not too distant past.
I'm not sure if the current model has it, but I somehow doubt it.

The difference is that FP sync fires the flash before the shutter
begins to open so that the flash intensity is even over the whole
period that the shutter is working. This way, even at maximum speed,
the flash will be working during the whole travel time of the
narrow gap between the two shutter curtains.

If a focal plane shutter is equiped with M sync, the flash contacts
close in time for the bulb to produce peak output when the first
curtain reaches the _end_ of the film gate. This is to allow M
class bulbs to be used at sych speed instead of the slower speed
which would need to be used if M class bulbs are used at X synchronisation.
It is possible to get away with one speed higher than the sync
speed with M class bulbs and M synchronisation on reasonably
fast focal plane shutters.

Many of the 35mm cameras from the former Soviet Union had
M sync available, but AFAIK the Kiev MF SLRs don't.

> Thanks for the informed response.

I checked my facts with the old Focal encyclopedia which
I think is a very useful book, so I'm pretty sure I'm getting
this right. (Besides, this is the only way that makes sense to me)

Peter.
---
pirwin@ktb.net


From: markc@panix.com.invalid (Mark Cudworth)
Subject: Re: Flashbulbs
Newsgroups: rec.photo.equipment.medium-format
Date: Wed, 22 Oct 2003 

kfritch@aol.com (KFritch) writes:
>The bulbs for focal plane shutters are #6 and 26. I unerstand the 22, 40, and
>5 can be used with focal plane shutters at speeds below a 30th. The Cress site
>is an excellent source for guide number and synch tables. It does not, however
>list the number 2 which I am asking about (or, for that matter, the number 8
>which seems to have similar characteristics with the Press 25 except that it is
>smaller in size)

Another site with flash bulb info is:

http://www.dhios.demon.co.uk/Flashbulbs/intro.html

There isn't a lot of information about the #2, but it is listed. The #8 is
listed and even has a picture.

--
Mark Cudworth








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