Re: PHOTO-3D digest 1294

[P3D Bob Howard <bobh@xxxxxxxxxxxxxxxxxxxx>]

Re: Resolution MTF John B. and Eric G. comments:

I think John B. has it backwards..the large format has poor resolution 
of lenses and depends on its fine definition and gradation on little 
enlargement of the film..near contact print. The Achilles heel of large 
format is the need for depth of field that forces small f/stops (large 
number) and these are never much resolution at f/16 or 22. Of course we 
now know that apparent sharpness is a contrast thing. MTF is modulation 
transfer function and can be done for film, lens, or both. IT was 
discovered by Schrade of RCA when investigation why lenses that tested 
lousy gave better TV images than renowned lenses. (All the surplus Ektra 
lenses were remounted for TV turrets on the first TV studio 
cameras!)BobH


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