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02-10-2021, 05:55 AM   #16
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QuoteOriginally posted by stevebrot Quote
I have puzzled over this and wonder if it has to do with field curvature. Dedicated macro and bellows lenses are designed to have very flat fields.


Steve
As I recall Modern or Popular Photography in the 80s recommended using normal (non-macro) lenses for slide duplication for this very reason. The exception would be with glass mounted slides which hold the film chip flat. A potential drawback of glass mounted slides is the possibility of "Newton's Rings".

02-11-2021, 04:55 AM   #17
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QuoteOriginally posted by stevebrot Quote
I have puzzled over this and wonder if it has to do with field curvature. Dedicated macro and bellows lenses are designed to have very flat fields.


Steve
I agree, in fact my bellows setup presently has a 135 mm enlarging lens mounted on it.

As you said, when I started photography in the 1980ís the flat field characteristic of macro lenses was always part of them being recommended exclusively for copy purposes.

I had converted an old B&W enlarger into a copy stand for document copying purposes
03-01-2021, 02:53 PM   #18
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So, today a frind of mine gave me a present. A macro Bellows and I've been tweaking all afternoon trying to make it work. I can't seem to fit the all the frame and at the time it being in focus. Just a small portion of the frame is focused and well, no so sharp when processed in LR.
this is the said bellow.
https://drive.google.com/file/d/1pScQEGPrAU1CN_fTnAtBPkYHaM-RGeIC/view?usp=sharing
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