Re: optics/Japan

[brian whatcott <inet@intellisys.net>]

At 00:14 11/6/97 EST, David Dockstader wrote:
> ... I was involved in making resolution test targets.  To
> produce these targets I made a series of photographic reductions of a master
> scribed on a glass plate.  The final reduction was made on a special emulsion
> coated on glass plates with a Nikon f1.2 lens that was virtually diffraction
> limited at full aperature over a 3mm field. We were able to resolve over
> 1800 lines/mm, but the only microscope lenses we could find good enough to
> evaluate our work came from Zeiss.  (The Nikon lens was a special purpose
> optic and not something designed for general purpose photography.)
I was surprised by the resolving power of the optics you mentioned.
 In the modulation tranfer function plots I am familiar with ( for cameras)
the resolution limit seems to occur around 300 line(pairs) per mm
at perhaps 5% modulation, with a more representative value of 180 lpmm
for reasonable modulation depth.

Brian Whatcott

brian whatcott <inet@intellisys.net>
Altus OK