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norm the storm
9-Feb-2013, 06:53
Hi everybodies

I have an old Seneca View Camera 11 x 14. I don't have any lens for now. I figure to get a lens this spring, a Karl Mayer 305mm f6.8 on an Alphax shutter or a 360 mm
Symmar f6.8. I bought a film holder 2 weeks ago. I did some measures with a micrometer on the back of the camera. For the holder, the distance from film slot and the border of the holder is .332 inch. For the back, I measured .285 inch between the interior of the GG and the border of the back, so a difference of .047 inch. My question is do I need adjustment on the back of the camera or is it right like that?

Thank you.
Any advise will be appreciated.

Jim Jones
9-Feb-2013, 07:13
Be sure the face of the GG frame fully contacts the back of the camera before relying on that measurement. Also, measuring from the face of the film holder to the face of a sheet of film should be more reliable than trying to measure the film holder directly. If there is enough slop in the film channel in the holder, inserting a fully exposed and developed sheet of film behind the unexposed film (or a cheaper substitute) would nudge the film in the right direction. If tests still show an actual focusing error on film, a scale and pointer can be installed on the camera. The pointer should be designed so, after focusing on the GG, the focus can be offset on the scale by the correct amount.

RichardRitter
9-Feb-2013, 07:26
The ANSI standard for the "T" dimension of a 11 x 14 film holder is 0.332. Make sure that the ground glass frame is not relieved in the center part of the frame. The frame could of been made to have the glass in backwards. This was done on early camera.

E. von Hoegh
9-Feb-2013, 08:40
Hi everybodies

I have an old Seneca View Camera 11 x 14. I don't have any lens for now. I figure to get a lens this spring, a Karl Mayer 305mm f6.8 on an Alphax shutter or a 360 mm
Symmar f6.8. I bought a film holder 2 weeks ago. I did some measures with a micrometer on the back of the camera. For the holder, the distance from film slot and the border of the holder is .332 inch. For the back, I measured .285 inch between the interior of the GG and the border of the back, so a difference of .047 inch. My question is do I need adjustment on the back of the camera or is it right like that?

Thank you.
Any advise will be appreciated.

Norm, something to be wary of is any lens marked "Karl Meyer". This is a made up name, used by Burke & James for god-knows-what glass they mounted and peddled. I've always thought they made up the name from Carl Zeiss and Hugo Meyer, bith respected German optical firms.

I'd go with the 360 Symmar myself.