Giant shutter?

[genotypewriter]

Hi everyone,

I'm looking for a shutter with an opening of at least 5" (127mm) that can do fast shutter speeds. I've spent a lot of time thinking about this and here are some points:


Opening and closing the lens with a cap is not an option
Custom Packard shutters are not possible due to both price and the limitation to 1/25 or so. I need the shutter speed to be adjustable.
DIY is an option and I've thought about guillotine shutters, rotary shutters as well as focal-plane-like shutters. The main problem I have is controlling speed.
The shutter can sit any where really. Assume that this is for a DIY 8x10 camera.


Any suggestions would be much appreciated!

[Old-N-Feeble]

Some folks gut an old 4x5 Speed Graphic for the focal plane shutter... speeds from 1 sec to 1/1000 plus T. But that's 4x5, not 5x5.

[IanG]

A Thornton Pickard focal plane shutter has a top speed of 1/1000 so should be fast enough, a bit rare though in any size.

Ian

[Jim Michael]

A guillotine shutter where you have a constant pulling force from a spring should allow control of shutter speed via slit width. I'd probably add some type of mechanism to reduce friction in the moving components like roller bearings, perhaps an ME would have a suggestion.

[ic-racer]

You may be able to make a large Magneto-optical shutter or Kerr Cell shutter.
http://webmuseum.mit.edu/browserview.php?kv=70151

[cosmicexplosion]

what lens/film configuration/application are you using/doing that needs faster than 1/25, just curious.

i recently aquried a 300mm aero ektar 'f2.5' so i am also, trying to find a large shutter.

"got me the shutter bug blues"

[Dan Fromm]

It pains me to bring them up because they're not common and shouldn't be destroyed, but there are 5x7 Speed Graphics (press cameras) and Graflexes (SLRs) with focal plane shutters.

Knowing what OP is trying to accomplish (lens' focal length and maximum aperture; shooting situation = film speed, desired aperture/shutter speed combination, image circle required) would be helpful. Some things just can't be done -- I suspect the OP has constrained himself into infeasibility, hope this isn't so -- but sometimes the apparently impossible can be done.

[genotypewriter]

Some folks gut an old 4x5 Speed Graphic for the focal plane shutter... speeds from 1 sec to 1/1000 plus T. But that's 4x5, not 5x5.
Yes, I got one for that exact reason to use on a 48cm f/4.5 Xenar but then I found a bigger lens :D



A Thornton Pickard focal plane shutter has a top speed of 1/1000 so should be fast enough, a bit rare though in any size.
Ian
That's an excellent suggestion, Ian. Didn't know about such a thing. Looking at what's up for sale, the shutters don't seem to be in good shape though.



A guillotine shutter where you have a constant pulling force from a spring should allow control of shutter speed via slit width. I'd probably add some type of mechanism to reduce friction in the moving components like roller bearings, perhaps an ME would have a suggestion.
I already made one with a relatively high torque 12V DC motor. The problem is making a variable slit shutter that's light enough to be pulled by the motor with the least amount of acceleration and not fragile at the same time.



You may be able to make a large Magneto-optical shutter or Kerr Cell shutter.
http://webmuseum.mit.edu/browserview.php?kv=70151
Reading up on it, it looks like there will always be glass in the middle. Will keep this in mind for a different project :)



what lens/film configuration/application are you using/doing that needs faster than 1/25, just curious.

i recently aquried a 300mm aero ektar 'f2.5' so i am also, trying to find a large shutter.

"got me the shutter bug blues"
Same lens... :D


It pains me to bring them up because they're not common and shouldn't be destroyed, but there are 5x7 Speed Graphics (press cameras) and Graflexes (SLRs) with focal plane shutters.

Knowing what OP is trying to accomplish (lens' focal length and maximum aperture; shooting situation = film speed, desired aperture/shutter speed combination, image circle required) would be helpful. Some things just can't be done -- I suspect the OP has constrained himself into infeasibility, hope this isn't so -- but sometimes the apparently impossible can be done.

Thanks, Dan. To answer your questions...

Focal length: Anywhere from 300 to ~500mm or maybe longer in the future. I intend to use this for several lenses.
Maximum aperture: The largest lens I have right now has a 120mm aperture. If you're wondering about the light transmission, it's around f/3.5.
Shooting situation/film speed: ISO100, on field.
Desired shutter speeds: As fast as possible. 1/500 if it's not too ambitious.
Image circle required: 8x10... so it's easier to install the shutter on the lens than on the focal plane.

Thanks again for everyone's suggestions.

[IanG]

Depending on the lens size one of the larger standard Thornton Pickard roller blind shutter (or similar) may be OK, I have a couple that would work with a 120mm diameter front/rear diameter lens. While these are usually 1/15th to a 1/90 there were higher speed versions - essentially they just need a narrower slit - would need to be front mounted in this case but 1/400th is possible. These do come up for sale occasionally or I get mine from camera fairs etc. I restored 3 larger ones last Spring.

If you found a Focal plane version with all its brass work then restoration is relatively easy. TP also made 10x8 cameras with built in FP shutters.

Ian

[Dan Fromm]

Hmm. 300 mm lens, 300 mm circle, 1/500. Hmm. According to a stupid little similar triangles model that I use to help me think about front-mounting, that can almost be done with a #1 close behind the lens.

A Compur/Copal/Prontor 1's maximum opening is 30 mm, lens' rear node-to-infinity is 300 mm, the circle covered is 300 mm. If the rear node-to-shutter distance is no more than 30 mm the shutter will vignette the circle to no less than 300 mm.

If you think hard about my little model you'll see that it isn't quite right. That said, I've shot a 480 Apo Nikkor on my tandem 2x3 Graphic with no vignetting. Filled the 2x3 frame with good image, corners weren't darker than the center.

There's a minor(?) snag with this approach when applied to lenses with large apertures. Basically the lens' diaphragm will have no effect on exposure -- the lens will effectively be at full aperture -- until the exit pupil is the size of the shutter's maximum opening.

The big idea here, OP, is that the shutter doesn't have to be as large as the lens' maximum aperture or the exit pupil if it is close to the lens. Don't scoff, try it.

[jp]

Some folks gut an old 4x5 Speed Graphic for the focal plane shutter... speeds from 1 sec to 1/1000 plus T. But that's 4x5, not 5x5.

It's really a little more like 4.5x5. There is some extra travel that is masked by the 4x5 back. It could be potentially the same shutter as used by an RB graflex SLR, which would do 5x5 because it's revolving back. In that case, one would have to be a better woodworker than I to get 5x5 out of it.

http://www.f64.nu/photo/tmp/lff/_DSC7351s.JPG http://www.f64.nu/photo/tmp/lff/_DSC7350s.JPG is the speed graphic focal plane shutter setup I use for a ~~4.5" rear element lens.

I don't know if this is close enough to the OP's goals. Another option would be a set of ND filters to allow more exposure flexibility with a guillotine or packard shutter.

If it's a homemade camera and the purpose of the lens is to shoot wide open, you better make it very solid at the front as any flexing will throw it out of focus at such a thin DOF.

[IanG]

The big idea here, OP, is that the shutter doesn't have to be as large as the lens' maximum aperture or the exit pupil if it is close to the lens. Don't scoff, try it.

Actually what you're saying Dan is similar to some pre-WWII lens hoods which had a plate at the front with a rectangular cut-out, Some Cine and Video lens hoods still use this system.

So a 5x4 Speed Graphic shutter should be fine.

Ian

[genotypewriter]

Depending on the lens size one of the larger standard Thornton Pickard roller blind shutter (or similar) may be OK, I have a couple that would work with a 120mm diameter front/rear diameter lens. While these are usually 1/15th to a 1/90 there were higher speed versions - essentially they just need a narrower slit - would need to be front mounted in this case but 1/400th is possible. These do come up for sale occasionally or I get mine from camera fairs etc. I restored 3 larger ones last Spring.

If you found a Focal plane version with all its brass work then restoration is relatively easy. TP also made 10x8 cameras with built in FP shutters.

Ian
Thanks, will keep in mind.



It's really a little more like 4.5x5. There is some extra travel that is masked by the 4x5 back. It could be potentially the same shutter as used by an RB graflex SLR, which would do 5x5 because it's revolving back. In that case, one would have to be a better woodworker than I to get 5x5 out of it.

http://www.f64.nu/photo/tmp/lff/_DSC7351s.JPG http://www.f64.nu/photo/tmp/lff/_DSC7350s.JPG is the speed graphic focal plane shutter setup I use for a ~~4.5" rear element lens.

I don't know if this is close enough to the OP's goals. Another option would be a set of ND filters to allow more exposure flexibility with a guillotine or packard shutter.

If it's a homemade camera and the purpose of the lens is to shoot wide open, you better make it very solid at the front as any flexing will throw it out of focus at such a thin DOF.

Thanks for the pointers. Yes, the bulk introduces more problems usually.



Hmm. 300 mm lens, 300 mm circle, 1/500. Hmm. According to a stupid little similar triangles model that I use to help me think about front-mounting, that can almost be done with a #1 close behind the lens.

A Compur/Copal/Prontor 1's maximum opening is 30 mm, lens' rear node-to-infinity is 300 mm, the circle covered is 300 mm. If the rear node-to-shutter distance is no more than 30 mm the shutter will vignette the circle to no less than 300 mm.

If you think hard about my little model you'll see that it isn't quite right. That said, I've shot a 480 Apo Nikkor on my tandem 2x3 Graphic with no vignetting. Filled the 2x3 frame with good image, corners weren't darker than the center.

There's a minor(?) snag with this approach when applied to lenses with large apertures. Basically the lens' diaphragm will have no effect on exposure -- the lens will effectively be at full aperture -- until the exit pupil is the size of the shutter's maximum opening.

The big idea here, OP, is that the shutter doesn't have to be as large as the lens' maximum aperture or the exit pupil if it is close to the lens. Don't scoff, try it.



Actually what you're saying Dan is similar to some pre-WWII lens hoods which had a plate at the front with a rectangular cut-out, Some Cine and Video lens hoods still use this system.

So a 5x4 Speed Graphic shutter should be fine.

Ian

Very interesting suggestion, Dan and thanks for clearing it up, Ian. I might try just that. My only reservation is though, the 4x5 Speed Graphics are pretty thick. Guess I'll have to hack it up a bit to know either way. If luck's on my side, it'll double as a lens hood too! :)


Thanks to everyone for the responses.

[genotypewriter]

So here's the update... putting the 4x5 Speed Graphic in front will indeed change the image. For things to not make a difference when the front element is partially obstructed (e.g. like with a front baffle), I imagine the image circle needs to be much larger than the film plane... and with my lens it's not.

Next step would be to try the same from the rear.

[cosmicexplosion]

Jello mr type righter
The guy I bought my ektar off of, used a seed graphic, I discovered on inquiry after reading this Fred.
Only he used a ploubel 8 10 that has a 9x9 lens board.
I believe he put it behind the lens to great effect.
I can send the pic he sent me if you are intensely interested.
But abreast I would like to kept of your developments
And more importantly I would like to see some images made with one as I have only seen one.
Do you know of any images any where?
Cheers
Andrew

[Drew Bedo]

What about the focal plane shutter from one of the Graqflex Reflex cameras" The RB series could shoot 4x5 in either landscape or portrate . . .the shutter must have been larger.

they made them in 5x7 as well . . .even bigger.

Make sure the doner body is a junker though.

[cosmicexplosion]

yeah i am in a bit of a fix as to what to do with this massive lens, it seems like i have to spend another grand just getting the ploubel 8x10 to be able to use it, good side, comes with working shutter, all rigged up.

i forgot to ask mr typewriter, what body are you using?

[Old-N-Feeble]

What about making a series of gravity drop shutters with various sizes of slots?

[domaz]

It's going to be tough to find a 5x7 Graflex focal plane shutter in good condition. I have a 5x7 Speed Graphic where the body is in great condition but the shutter cloth looks like it could explode at any moment (still light tight and works though). From what I've read this is a common affliction for these older shutters and there are few repairmen who know how to replace them.

[cgrab]

The East German "Mentor" cameras might be possible donors. Check them on German ebay, there are two monorail models 13x18cm and 18x24cm with a shutter mounted behind the lens, which was up to 300mm f4,5, and a 13x18cm folding model with a shutter in front of the film holder. Unfortunately, I do not have any personal experience with either. They seem rather primitive, but this might be an advantage in your case, and they come up fairly regularly.

[cosmicexplosion]

interesting cgrab, thanks.
i just looked on ebay de, and yes there is a 13x18 with shutter, the aktar is f2.5, so i am not sure how big the shutter opening is in mm, any chance you could find out, my german is a bit rusty, thou i could use google translator?

mr feeble, what is a gravity drop shutter? is it just something you let drop,?

[Lachlan 717]

Gravity drop shutters are long strips of card/board/plastic/metal that have a given spacing in the middle. So, you start with the strip up high (where the bottom, solid section acts as a closed shutter), and drop it.

The gap acts somewhat like a curtain shutter, where the length of the gap determines the exposure time (longer gap=longer exposure).

The solid top section then also acts as a closed shutter.

Better get accustomed to working out fractions of 9m per second per second...

[numnutz]

Gravity drop shutters are long strips of card/board/plastic/metal that have a given spacing in the middle...

like this one...

http://www.youtube.com/watch?v=0F7LZiQHsqo

nn :)

[Old-N-Feeble]

Here's another link: Guillotine Shutter Design (http://www.largeformatphotography.info/guillotine-shutter/guillotine-shutter-construction.html)

[polyglot]

Have you thought about using a slab of LCD? They don't have a huge Dmax but it's probably enough to get you a fastish (1/100) shutter if you cover it mechanically with something slower.

Edit: supplier (http://www.liquidcrystaltechnologies.com/products/LCDShutters.htm)
Edit II: I emailed for a 150x150mm price. If they're affordable (~$100), I could feasibly build a batch of electronic shutters for people here to buy.

[TheDeardorffGuy]

Have you thought about using a slab of LCD? They don't have a huge Dmax but it's probably enough to get you a fastish (1/100) shutter if you cover it mechanically with something slower.

Edit: supplier (http://www.liquidcrystaltechnologies.com/products/LCDShutters.htm)

Last year in Chicago I saw a photographer shooting a Deardorff V11. He had a 7x7 board with huge Nikkor APO on the front. there were wires coming out of the board to a controler. I asked him if it was a Packard Shutter. Nope! He smiled and removed the board and showed me a totaly opaque LCD glass mounted to the rear cell. The LCD glass was capable of on off on cycle of nearly a thousanth.His controler was adjustable from 10 minutes to 1/1000. I have not looked up LCD glass. Sorry. It looked very clear when on.

[Jody_S]

As an occasional DIY-er/builder, probably the easiest system to build from scratch (well, 2nd to the 'gravity shutter' setup) is a rotary system. Basically, you need a spring/elastic/electric system of rotating a large wheel with a slit in it, and you simply make as many wheels as you need speeds by varying the width of the slit. If you're able to make a multi-speed rotation device, that would obviously reduce the number of wheels you need to carry around. 2 wheels in a sandwich, making a variable slit? None of this is hard to make with basic hand tools and some sheet metal.

[polyglot]

They replied that tooling setup for 150x150 shutters would be about $2500, though they're already setup to produce 100x100 pi cells for $100 each, plus a bit extra for compensating film.

They're not big enough for craziness like a 300/2.5, but you could happily shoot 200/2.5 or 360/4 through such a shutter. By the time you add a controller and mechanicals, you'd be looking at probably $300-400 per shutter, which I think is well reasonable for such a huge size and the ability to do 1/500 up to hours, not to mention intervalometer behaviour. If you were very DIY-capable, you could do a basic materials-only for about $150 I think.

Would people here be willing to buy 100mm shutters for about $400?

[buggz]

I would, though, complete specs would be needed.



Would people here be willing to buy 100mm shutters for about $400?

[cosmicexplosion]

i think i might use a hat!

[cgrab]

Sorry for answering late, I have been away. I could not find any information concerning the shutter diameter for the front mounted shutter model. I bought one, it should be delivered nest week, and I will measure and post the size of the opening. On the rear mounted shutter of the folding model, shutter size must be relatively close to 13x18/5x7, as shutter and film plane are quite close together.

The idea of an LCD shutter sounds fascinating.