From: mcdonald@aries.scs.uiuc.edu (J. D. McDonald)
Newsgroups: sci.astro
Subject: Re: > C8 stories + radial guider bug
Date: 27 Aug 92 19:06:38 GMT
Organization: UIUC SCS

In article <-xcn+bb.benoit@netcom.com> benoit@netcom.com (BENOIT SCHILLINGS) writes:


>Could someone raytrace a star image at 0.5 inches from
>the optical axis for a C8 f/10. This could be
>the best way to know for sure.

Sure. This is actually for a Meade 8 inch f/10, but Celestrons
are essentially identical.

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end


The dimensions are in inches. You'll note that coma predominates,
but lurking under there is indeed lots of astigmatism. My tracer 
program does not give a breakdown into the primary aberrations,
just the spot diagram. You'll note the abysmal image. Yes, experiment
agrees.

Doug McDonald
Xref: sparky sci.astro:9446 sci.geo.meteorology:2998 rec.radio.amateur.misc:14980 rec.radio.shortwave:6687