Re: Kohler illumination question...

I agree with Dr. Resnick. I've read in several publications (all
forgotten!) that true Kholer illumination requires a clear light path
from the light source onward, to achieve maximum performance from the
filament's light rays. The frosted filter is a compromise to the
somewhat tedious task (say some) of setting up true Kohler
illumination. Some very good information on Kohler illumination can be
found in the most recent edition of Kodak's "Photography Through the
Microscope", written/revised by John Gustov Delly.

Bob Marable

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