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Bill Glickman
18-Sep-2001, 05:36
I am trying to mount two modern 80mm (or 70mm)lenses side by side on a LF lens b oard for shooting stereo. My goal is to find a modern sharp lens where the diam eter of the widest part of the lens (usually the shutter) is 60mm or less. I be lieve all Copal 0's are wider than than 60mm. Coverage requirments is only 6x6, any suggetions? New digital lenses? Thank you.

Kevin M Bourque
18-Sep-2001, 09:28
Bill -

Here's an option - the "lower" component from a Mamiya TLR lens. I don't have one in front of me, but I think the filter diameter is 46mm, and the shutter isn't much bigger. There's a retaining nut on the back of the "lens board", just like you'd expect. Remove it, and the flash sync wire, and you're good to go.

I don't know if you could expect to put Humpty Dumpty back together again, so you'd be ruining the lens for future use on a TLR.

The shutters don't have cable release sockets, just trip levers, so you'll have to invent some mechanical linkage to trip the shutters.

I know some of these details because I tore apart a damaged 80mm lens some years ago (couldn't resist it). I might still have the lens and shutter around somewhere.

eBay has older used ones all the time. It might be a fairly inexpensive option.

Good luck!

Dave Willison
18-Sep-2001, 09:36
Bill:

Take a look at the following page. This particular hand-built camera uses two 65mm Super Angulons, although they are not mounted on a LF lenseboard and camera.

http://www.ghouse.com/daniel/stereoscopy/equipment/index.html

I believe that the older 65mm SA (often mounted in a syncho compur shutter) is less than 60mm. In fact the widest part of these lenses is the front element which measures about 55mm using the lenscap as a guide. In addition, the rear relement is about 42mm and the retaining ring is approximately 30mm.

If my calculations are right, two of these lenses would require a lensboard that is at least 4.25 inches wide. This is based on the assumption that the lenses are mounted side-by-side and spaced 65mm from center to center. I don't remember the exact requirements for stereo, but this figure seems about right depending on the subject distance. This also assumes a 1/4 inch margin around the lensboard holes and adequate space for some clearance between the front elements.

It would be easier to mount these lenses on a 5x7, but your 4x5 may work if the camera has a large lensboard. The other problem to keep in mind is whether your camera belows is compact enough to focus a 65mm lense at infinity.

I hope this helps and let me know if you need more exact dimensions on the older SA.

................................

Jim Galli
18-Sep-2001, 12:44
OK, this is a little far fetched but I'm just going to throw an idea out there that might be buildable. What about those Polaroid ID camera things with the twin 75mm lenses with adjustable apertures, and the shutter is just 2 round holes that rotate on a common axle to line up with the lenses and then close again? They're nearly worthless on Ebay because digital does the job they were originally designed to do much better now. You could always put better glass in front of the rotating shutter, although some of the Polaroid glass wasn't too bad.

Doug Paramore
18-Sep-2001, 13:49
Bill: I have a match to Kevin's Mamiya TLR lens you can have if you want to go that route. I have no need for it.

Regards,

Bill Glickman
18-Sep-2001, 16:01
The Mamiya TLR lenses were popular for this application for years, and still is due to their small size. I was hoping to find some modern optics that would produce sharper chromes for this application, but I guess I can not rule out the mamiya TLR lenses. The Super Angulons used on the stereo camera which you provided the link have copal 0 shutters I beleive...for his camera it is acceptable since he shoots two 6x9 frames, while I am trying to shoot two 6x6 frames on 4x5 film, so therefore the maximun diameter of the lenses would need to be 59.5mm, otherwise, I can not center the images over the tight fit for two 6x6's. I plan to use a very thin septum between the lenses. Thanks for all the input.

Does anyone know if the Rodenstock or Schneider digital lenses can be fitted with smaller shutters, i.e. not Copals?

Bob Salomon
18-Sep-2001, 18:00
No they can't.

They have either 0 or 1 size threads.

"Does anyone know if the Rodenstock or Schneider digital lenses can be fitted with smaller shutters, i.e. not Copals? "

want a brochure?

Bill Glickman
18-Sep-2001, 18:15
Bob, yes, I will take the brochure if you feel these lenses will accomplish my task. But from what you wrote above, it seems they would be too wide, right? I have no way to check the dimensions on the web for the Rodenstock digitals. Can you advise?

Bob Salomon
18-Sep-2001, 18:46
There is no way to screw them into a shutter smaller then a 0.

For a brochure we need a mailing address.

Struan Gray
19-Sep-2001, 10:48
You might just be able to squeak two Mamiya 6 or 7 rangefinder lenses in there (58 mm filters), but you'll have to control the shutter yourself. Otherwise the only thing small enough is going to be the lens off a MF folder, with the expensive Plaubel Makina lenses amongst the most modern.

Can you use a focal plane shutter? That would at least give you the chance to use something like an enlarging lens or - a compromise - a normal lens from a focal-plane 645 SLR like the Pentaxes and Mamiyas. Alternately, it would let you get the cells from a small view-camera lens re-mounted into a barrel.

adam friedberg
19-Sep-2001, 19:56
the makina lenses - at least with the shutter - are very large.