On Fri, Jul 16, 1999 at 03:49:52PM -0400, Skip Williams wrote:
> < Precision-made body caps, made from converted manufacturer's caps, have a
> .259mm pinhole, approx. focal length of 50mm, approx. f/185 [...]
Okkay, I give up. How does one control the focal length and/or aperture of a
pinhole? What does varying the pinhole's size _do_ in that regard? For that
matter, isn't the focal length of a pinhole the distance from the pinhole
itself to the film plane? ...so while the focal length of the OM pinhole
would be about 50mm (register distance of the lens mount plus thickness of
the front part of the cap, roughly), the focal length of the M645 pinhole
would be substantially longer because of the greater register distance? Am I
missing something simple here?
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