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Re: [APML]: Celestron FastStar
> From: Ian Turner <skyshooter@mindspring.com>
> I have the chance to aquire one in the next few days. I was wondeing if
> anyone new of a very small 35mm film holder that I might be able to place
> in front of the corrector where the CCD camera is suppose to go?
>
> The little scope setup like this should yield a F Ratio of 1.95 with 8 "
> apeture and hopefully not that big a central obstruction.
>
> Any comments would be appreciated.
Unless Celestron has taken steps to flatten the field (I seriously
doubt they have) then you will only be able to use a small part of
the 35mm frame. . .and I betcha it's an area about the size of the
CCD chip they use in the FastStar.
Or perhaps you'd have to rig up a curved film holder to curve
individual cut pieces of 35mm film - pretty much like a schmidt
camera. The radius in this case would be the focal length of the
system, 8 times 1.95, between 15 and 16 inches. Note: This will
not give as sharp off axis images on 35mm film as a genuine schmidt
camera because the corrector plate is not at the radius of curvature
(the optimum location of the corrector for a schmidt camera).
Tom Krajci
Capt Tom Krajci
B-52 Intelligence Officer
"Trust. . .but verify! (Soviet maxim)"
http://spur.barksdale.af.mil