Using a Speed Graphic Focal Plane Shutter in other LF cameras for barrel lenses?

[Asher Kelman]

Asher,

there was/is an Apo Germinar 750 Copal 3 factory mounted by Carl Zeiss-Docter Optics that would allow to get rid of some of the shutter issues ..You do not find them too often.. and if so they may be not cheap,

Joerg,

That's a great idea if one appears. I wonder whether or not that takes away several stops? I'd be impressed if it was still f 9.0 or abouts. Still, one needs to mount he 47 1/2" Red Dot Artar. That, perhaps, might go in an Ilex #5.

Asher

[Asher Kelman]

The flash contacts on the focal plane shutter of my Pacemakers close a little before most slits begin to traverse the film gate. This permits the light from a slow-burning focal plane type flash bulb to build up to near maximum before the exposure begins. One exception is the "T" position. There the contacts close just after the shutter fully exposes the film gate to sync with any flash. A fast finger on a smooth running Pacemaker shutter could sync at about 1/4 second.

Another idea: the "T" flash contacts could be relocated to close just before the shutter curtain closes for an equivalent of rear curtain sync.

Jim,

That's something worth playing with. Do you think one can do that without destroying the Pacemaker or would one just sacrifice the grand old camera for the cause?

I'd still go for a prime solution right now with the Packard, as there are so many parts to put together and test in the entire camera.

Asher

[jp]

I've got a speed graphic for this sort of project the OP has proposed. I haven't adapted it yet. I intend to sandwich it between two lensboards and have it in front of the fron standard. One board to attach it to the camera, one to mate with another lensboard.

While it technically could be installed behind the standard to balance things weight wise, you'd have to remove it to cock it and open it, which would be a PITA.

Also on ebay check out 150627763348 ; more than my budget but a great idea.

The Sinar shutter is very nice, but it does not have a big enough diameter for lots of the old lenses.

If you stick with a 1-speed packard, you can use ND filters to provide more exposure options for a given aperture. I'm mostly interested in soft focus and thin DOF stuff for real old lenses, so I can't just stop it way down to get a workable leisurely shutter speed outdoors.

[Tracy Storer]

Sinar shutter sitting on my desk, max opening = 2.95" or 74.9xmm.
I think a Packard will suffice. 5" ones are probably not "in stock" but can be made. (I had to wait a couple weeks for a new 5" #6 a couple months ago, but it is nice)

[Hugo Zhang]

Asher,

I asked Ron to make a slip-on focal plane shutter that I use for my Xenotar 460mm lens which has a front diameter of 5 1/2" and it works.

http://www.largeformatphotography.in...ad.php?t=51309

Good luck with your project.

Hugo

[cyrus]

There was actually an 8x10 back attached to a Graphic on ebay last night. My first reaction was to whince at the butchering of the Graphic

[Asher Kelman]

Asher,

I asked Ron to make a slip-on focal plane shutter that I use for my Xenotar 460mm lens which has a front diameter of 5 1/2" and it works.

http://www.largeformatphotography.in...ad.php?t=51309

Good luck with your project.

Hugo

I read about that guy! Reminds me of Littman! Very independent and poetic descriptions! Didi you time it?

Asher

[Jim Jones]

Jim,

That's something worth playing with. Do you think one can do that without destroying the Pacemaker or would one just sacrifice the grand old camera for the cause?

I'd still go for a prime solution right now with the Packard, as there are so many parts to put together and test in the entire camera.

Asher

There should be plenty of Pacemaker SGs with good shutters, but in other ways beyond restoring to full functioning. There are also enough Pacemakers to satisfy those with the desire and money for a really clean one. I certainly wouldn't butcher a really nice camera, but a fixer-upper is better put to any use than thrown out.

[Kimberly Anderson]

A student of mine just bought a baby Speed Graphic ( 2 1/4 x 3 1/4) and I'm thinking of getting one myself. Chopping it up and making it a front mounted shutter don't bother me much...just looking for ideas to see if anyone else had finished this project and if so, how it was working.

[Leicaf16]

Domenico Foschi had one like this that he used on a Kodak 2D 8X10. It was big clunky ungainly and a huge stress on the front standard which had to hold the weight of the mechanism and also account for the heavy brass lenses now being cantilevered out in front.

Also when it is in front you are NOT getting the advertised speeds. I once calculated that the eighth inch slit on one of those actually takes about 1/12th of a second to travel. At the focal plane right next to the film that means that during that time only the fraction of the film directly in front of the slit is being exposed. Out in front of a lens the light will go through the slit and fan out everywhere. I don't know how to calculate what an effective shutter speed would be in that case. Easier on a movie camera where you have knowns like shutter angle and rotation speed to work with.

Another thought; with a moving slit you cannot have any flash sync., something that seems to me would be a show stopper for your application. Far easier to let the flash decide the speed than fiddling with shutters. Packards and Sinar's can sync up easily with flash.

All of that aside, it did in fact work and Domenico got excellent results with his. Me, I've learned to live within the constraints of a Packard's 1/25th speed which is quite repeatable. The Sinar is far more elegant.

Hi Jim, hope you are well. I read your comment last night and it took a while to get my head around it. Surely the curtain speed is constant no matter where it’s placed. But then as I thought more about it I realised that because of the “fanning out” effect the film is being exposed for longer than if the slit was right in front of the film. So the shutter speed is still constant, but maybe the effective aperture of the slit is what is causing the increase in exposure? Just a thought. Knowing stuff is not my strong point