Have been trying to come up with a way to test my lenses for resolution and sharpness at each of their f/stops and then creating a quick reference chart for each lens. I don't have a 120 roll film back any more and shooting probably an average of 6 sheets of 4x5 film for each lens seems like a very daunting expensive project to start and then follow through with.
So came up with the following: Mount my Nikon FX digital camera body onto a Sinar lens board using an older extension tune to get clearance for the body. Then mount it onto the rear standard of the 4x5 Sinar Norma, and mount the view camera lens on the front standard. Create a resolution chart/target mounted in front of a lightbox say about 20 feet away (all done under controlled and repeatable conditions in the basement). Turn on the camera to LIVE VIEW to focus the lens. Now increase the magnification of the image on the back screen and focus. Then I figure I should be able to stop the lens down at each aperture and view and note the image sharpness change on the rear screen. Many years ago did the same for the macro lenses that I was using on a Nikon Multiphot but back then had to do it with film and had to buy a microscope glass slide with a resolution target on it. One exposure for each T or f stop, process the film, then view the negatives through a low power microscope, and then carefully make lens sharpness notes for each lens at each of its apertures. If I recall, this took me 3+ nights to do for 5 lenses, but the lens performance info was invaluable from then on. With the magnified LIVE VIEW screen, should take me 5 or 10 minutes per lens. Also should be able to detect any focus drift. I'm not interested in calculating lines/inch, but only in getting a general idea of how each lens performed.
Has anyone tried something like this? Would appreciate any advice before I permanently dedicate and epoxy a Nikon extension tube to a Sinar lens board.
Thanks
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