[LargeFormat] Re: lens corner definition

philip Lambert largeformat@f32.net
Fri Dec 8 03:08:47 2000


I think someone recently talked of using a 90mm Angulon on 5x4 and stopping
down to f32 for maximum sharpness in the corners.  There is an excellent
lens test table published on the Net by Christopher M. Perez/Kerry L.
Thalmann- showing definition in centre, middle and corner of field for
dozens of lenses.  The conclusion might be drawn that stopping a lens down
to minimum aperture does not optimise definition.  I expect diffraction is
the problem  F22 or F16 is fine.

Philip Lambert