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Mikkel McAlinden
18-Dec-2007, 01:18
Help! Anyone! I want to take pictures of extreme movement with a large format camera. Has anyone ever heard of a lens being manufactured which has a higher shutter speed than 1/500, hopefully 1/2000? I think maybe the central shutter is too complex to allow this. Is it possible to build a spring-loaded double aperture which would work like a really quick eclipse. I know you can use a flash in a dark room with an open lens but what I'm planning isn't possible in a dark room.

Martin Miksch
18-Dec-2007, 01:54
What I know the quickest is a Super Speed Graphic with 1/1000.
Regards
Martin

Peter K
18-Dec-2007, 02:05
Years ago Minolta made a central shutter with 0,5 ms (1/2000s). But with a small aperture. The problem with shutters is one has to accelerate a mass and to stop it "in no time". At a certain mass the materials like springs, bearings and shutterblades cannot bear this forces. This is also a problem with focal-plane shutters in the size for LF-cameras

There are other shutter-systems aviable like the "Kerr-Cell", working with liquid crystals and polarizers. But they need high-tension and other gear.

Peter K

Ole Tjugen
18-Dec-2007, 03:14
How is your German, Mikkel?

http://www.kamera-geschichte.de/files/verschluss1_d.htm has details of just about every classic German shutter, and mentions in passing that there were som special shutters that reached 1/2000, but these are rare (and unreliable).

If it is possible to adapt a Prontor 1000 LK or 1000 S to large format (the shutters were made for 35mm cameras), that will probably give the highest realistic shutter speed. I might even have one I could give you... :)

Donald Miller
18-Dec-2007, 03:18
It makes no difference if your room is lit or unlit. You can still use flash to stop action regardless of a shutter that is slower than you wish. It is simply a matter of arriving at a strobe exposure with sufficient output to override the room lighting. It is a matter of lighting ratios...you can make a fully lit room appear dark with sufficient strobe output. In considering this, if your room light is metered to give a Zone V exposure (in Zone speak) and your strobes are metered to give you four stops less exposure (four stops more light) and you base your exposure on the strobe exposure values, the area not lit by the strobes will appear to be dark.

Another consideration, should you decide to follow this direction, is the flash duration. With large amounts of movement, a shorter flash duration will stop action better.

Mikkel McAlinden
18-Dec-2007, 12:30
Thank you all so much for your quick and illuminating replies (no pun intended)! It is a quaint problem indeed. Martin, the Super Speed Graphic was discontinued due to .. wait for it .. mechanical problems. Peter, your information on Kerr-cell shutter systems seems advanced and interesting, although as yet I haven't found a commercial/practical application I can use. If you have more information I would be very grateful. Ole, technical German is I'm afraid uphill all the way for me, my school german is disappointingly insufficient. Donald, I agree that flash/strobe is a possibility and I have used it in similar scenarios before, (see: www.mikkelmcalinden.com , first floor 13-16), but the amount of flashes or strobes needed for my idea would be immense - and I''m still not sure it would work.

Peter K
18-Dec-2007, 12:56
One application for the Kerr-cell is the movie soundtrack. To get the high frequencies the exposure times must be as short as 1/20 000 second.

Peter K

Dan Fromm
18-Dec-2007, 12:56
Speed Graphics' focal plane shutters' top speed is 1/1000. But the slit's traverse time is on the order of 1/5. I think it might do for the shots you directed us to.

David A. Goldfarb
18-Dec-2007, 13:13
My 5x7" Press Graflex, circa 1921, has a focal plane shutter that can do 1/1500 sec., but like the Speed Graphic, the traverse time is around 1/5 sec., so there could be some Lartigue-type distortions. If you want to capture things like cards flying in midair, though, I think you need strobes at low power for short duration.

Jim Galli
18-Dec-2007, 13:18
What are you gaining for this type of picture by using large format? Why not do it with a 10mp Nikon? It seems to solve every problem. DOF, speed, etc.

Mikkel McAlinden
18-Dec-2007, 14:08
Dear all, you are energetic elves! Peter your information on Kerr-cell sounds very optimistic, send me your e-mail and I'll tell you the big idea, maybe we can figure something out. Dan and David, thank you for your information on Speed Graphics and Press Graflex - it's a good back up, and something I will investigate further. Ah Jim! Where would the fun be in that? And since this is large format photography - How dare you blaspheme! No seriously, as I've seen from your images which I enjoyed, we're all a bit hooked on this strange fetish of making photographs seem real and the more information we can shove into an image the better.
____________
Then I went back into the house and wrote, It is midnight. The rain is beating on the windows. It was not midnight. It was not raining.
Samuel Beckett, Molloy

bbjorkum
18-Dec-2007, 18:05
Well, if you'd go for a Speed Graphic, you could try to modify the curtain by reducing the slit width. I don't think there's more tension left in the bottom roller to tighten it up as much as you'd like. Anyway, it's a big leap from 1/1000 to 1/2000 ... You could try to approach http://www.johndesq.com/

Brian Ellis
19-Dec-2007, 12:31
Horses for courses. Your equipment doesn't seem well suited for the project you have in mind. Time to think . . . gasp . . . digital camera. :-)

Nate Battles
19-Dec-2007, 12:42
A few years ago there was an article in VC about a guy who photographs space shuttles during lift-off, he had an electronic shutter mechanism that fired very rapidly. I don't remember now if he made it or what. I realize this is probably not helpful at all. But, if Steve Simmons is around here, I am sure he'd know.

Ole Tjugen
19-Dec-2007, 13:55
You may be asking the wrong people here, I think.

Not that there is anything wrong with the people here or their technical knowledge, it's just that the person I know of who is best qualified to help you is "Gadget" Gainer.

And he's mostly over on apug.org...

Eric Woodbury
19-Dec-2007, 18:14
How about a rotary shutter? What kind of speeds can one get with a rotary? You might have to build your own and mount a lens around it. Just a thought if it has to be LF.

Gordon Moat
19-Dec-2007, 20:29
The Sinar M shutter (http://www.sinar.ch/site/index__gast-e-1793-50-1914.html) system, which will fit onto the Sinar P3 (http://www.sinar.ch/site/index__gast-e-1881-23-2008.html) view camera, has a fastest shutter speed of 1/2000. Definitely not a cheap system, but it will work. This could be considered more a medium format system than large format. However, I suggest you contact Sinar (http://www.sinar.ch/site/index__gast-e-1069-23-1151-urlvars-rand-393.html) directly and ask them about your imaging problem; they might have some quite good suggestions for you.

Ciao!

Gordon Moat Photography (http://www.gordonmoat.com)

Mikkel McAlinden
20-Dec-2007, 09:54
Dear All, I'll try to answer. Brian and Gordon I agree digital is possible albeit expensive. Digital photography has it's positive aspects. I am in fact known for my use of digital manipulation, but I still use film. The downside of digital photography is it's rotten at the core namely the RGB receptors. Highlights always result in "banding", my idea has an infinite amount of highlights and banding really is horrible and breaks the contract with the viewer. Nevertheless I have asked for more info from Sinar. Eric, a rotary shutter may be a possibility similar to some ideas I've had do you have any more information? Ole, thank you for your tip. I will post my question also at apug.org.

David Millard
20-Dec-2007, 18:15
Mikkel -
John Brackenbury designed and made a high-speed shutter consisting of a metal plate with a small 3-4mm aperture fitted in front of the lens, and a single pivoting solenoid-driven shutter vane, to achieve some of the incredible images that appear in his book "Insects In Flight". I'm not sure whether this would be helpful for your goals, but I would be happy to send you a copy of the pertinent pages. If I recall correctly, Stephen Dalton may have also discussed high-speed shutter design in some of his books.

Ernest Purdum
21-Dec-2007, 10:47
High-speed large format shutters have always been rather prone to suicide, ever since the Prosch "Athlete" which obtained its speed by the brute force of two big coil springs. The Super Speed Graphic shutter was much more scientific. Even though many have failed beyond repair, some are around still in working condition. If you got one of these and had it CLA'd, that would probably be reliable.

There was also the "Multispeed" shutter, for which, if I remember correctly, 1/2000 was claimed, but the chances of finding one which could be put into good order would be poor. I did see, though, one which was claimed to work on eBay recently.

Ernest Purdum
21-Dec-2007, 11:10
Ole, you are forgetting that before German camera makers started buying all their shutters from Gauthier and Deckel; Voigtlander, Kruegener, Wuensche, Zeiss, ICA and others made their own "classic German shutters".

Ole Tjugen
21-Dec-2007, 11:29
Ernest, see post #4. I'm not forgetting it at all!