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View Full Version : Help with fresnel/glass setup - TK 45S



bernal
3-Oct-2008, 13:06
Hi All,

although I searched in the fourms and found some information about it, I'm still confused as to what exactly it is what I have. I recently purchased a used TK 45S that has the following glass/fresnel set up: fresnel has frosted side facing the lens resting on the 4 metal strips and the circular grooves facing the photographer. On top of the fresnel is a piece of clear glass, presumably to protect the fine grooves. I know this is not a factory set up, and hope that other TK users can help me indentify what brand-name the fresnel might be and the purpose for this set up. Could it be Linhof's super screen? If so, since the piece of galss is clear, I would assume the image registration would be on the frosted side of the fresnel.

I did and image registration test using the described set up and it's definately off. After my test, I noticed the fresnel was warped, so this is probably why the registration was off. I then switched things around and moved the glass closest to the lens and the fresnel to the photographer side (frosted side facing the photographer) and did another test... still off. For my test I used a Fuji Quickload film holder, which is what I use for general shooting with no problems.

Would I be better off buying a groundglass and set it as factory default and then use the fresnel on top of it? Of course, I would still need to do another test. I hope the former owner didn't mess up with the four shim-adjusting screws. I should mentioned that other than the set up, nothing else seems to have been modified. It has the two black metal strips that hold the fresnel and glass together with the two small clips in the middle.

Thanks for your help.

bernal

Bob Salomon
3-Oct-2008, 14:01
You have a Super Screen. The best choice would be to switch to the standard Linhof grid ground glass and the Linhof fresnel. You should have fresnel clips on the middle screw of the GG hold down at either end of the GG. If not you would need new ones from Marflex. DO NOT ADJUST THE SCREWS THAT CHANGE THE SHIM POSITIONS!

We had recommended that the Super Screen be used with a spacer under each of the long sides between the camera back and the bottom of the Super Screen. This helped to prevent warping/bowing.

If yours has warped/bowed then it has to be replaced. The Super Screen has been out of production for several years.

bernal
3-Oct-2008, 14:26
You have a Super Screen. The best choice would be to switch to the standard Linhof grid ground glass and the Linhof fresnel. You should have fresnel clips on the middle screw of the GG hold down at either end of the GG. If not you would need new ones from Marflex. DO NOT ADJUST THE SCREWS THAT CHANGE THE SHIM POSITIONS!

We had recommended that the Super Screen be used with a spacer under each of the long sides between the camera back and the bottom of the Super Screen. This helped to prevent warping/bowing.

If yours has warped/bowed then it has to be replaced. The Super Screen has been out of production for several years.

Thank you Bob -

As I mentioned, the fresnel was warped, but when I took it apart it seemed to have gone back straight. Anyway, what is the manufacturer's part number for the standard groundglass? I think I'll go with your recomendation.

Thanks,

bernal

Bob Salomon
3-Oct-2008, 15:32
Thank you Bob -

As I mentioned, the fresnel was warped, but when I took it apart it seemed to have gone back straight. Anyway, what is the manufacturer's part number for the standard groundglass? I think I'll go with your recomendation.

Thanks,

bernal

021805

bernal
3-Oct-2008, 15:34
021805


Thanks again, Bob.

bernal