someone wrote:
=========================================
We tend to think of film as having zero thickness, while the emulsion
in reality is some small fraction of a millimetre in thickness. To
get a sharp picture you need "depth of field" (or whatever) to cover
the thickness of the emulsion. In practical terms this translates to
the effective resolution of the film is depending on a combination of
focal length and aperture.
While I can not quantisize the effect right now, I am certain that the
effective circle of confusion becomes smaller with smaller aperture
and thinner emulsion.
=========================================
ok, I'll buy that, but it doesn't address the issue of
whether the change in film resolution at different apertures
has any practical significance at the thicknesses typical of film.
with film being so thin, does this mean it might be capable of, say
79.8 lp/mm at f/2 and 80.1 lp/mm at f/11?
or maybe even 79.995 lp/mm at f/2 and 80.005 at f/11?
Joseph
< This message was delivered via the Olympus Mailing List >
< For questions, mailto:owner-olympus@xxxxxxxxxxxxxxx >
< Web Page: http://Zuiko.sls.bc.ca/swright/olympuslist.html >
|