Tolerance of Fidelity 11X14 Holders; Flatness Issue ?
Hi Folks,
Good morning/evening and thanks in advance for your valuable contribution/help.
Wondering how much a film holder should be flat, specially the ULF Fidelity 11X14 ?
Just acquired a used pair of them, thought Fidelity is the best among others specially wood types.
Did not yet used them. But did a simple flatness test. I aligned both holders parallel, each holder is resting on the Rib-lock of the other holder. If both holders are flat, the space between them should be the same in the middle and at both ends.
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Unfortunately, I noticed they are curved away from each other at center when aligned parallel. A larger space between the two holders at the center compared with the space at both ends.
The opposite alignment produces opposite observations. The space between the two holders at the center is narrower(holders actually touching each other) compared with the space at both ends.
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Here are some photos at center and at both ends, to compare the space between both holders, and to conclude on their flatness. Each pair of photos was taken at the same alignment scenario:
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I think, plastic holder specially the LF/ULF, when stored in a hot weather for enough time, can lose its flatness.
Now, my queries:
1. Is it normal for used Fidelity 11X14 holders ? Holders by the way are in excellent cosmetic condition.
2. Does it affect sharpness on 11X14 film ?
3. Can that magnitude of curvature be covered by the depth of focus at say f/32 in landscape photography ?
4. Is it correctable ?
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Thanks so much again, and please enjoy your time.