Re: [ATM] How fast is 150mm f/3.3 lensless Schmidt?

["Bob May" <rmay@nethere.com>]

He mentioned the lensless version where the aperture stop is at
the ROC of the mirror.  All this does is eliminate any coma from
the image plane which is still curved.
Considering the film grain size, you have to remember that
anything under a half a thousnadth of an inch for a spot size is
still perfection to the film used.  With today's CCD cameras,
that won't cut it tho.   Then again, find a CCD with a curved
imaging surface!
Bob May

rmay at nethere.com
http: slash /nav.to slash bobmay
http: slash /bobmay dot astronomy.net


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