Re: [ATM] 8" Diagonal- More info

["Dream - Telescopes & Accessories, Inc." <shane@dreamscopes.com>]

Mark,

It appears Scott will be at 0.7 arc seconds/pixel with his 28" f3.7 and 
STL-11000 combination.  Correct me if I'm wrong Scott.

Thank you.

Sincerely,
Shane Santi - Owner
Dream - Telescopes & Accessories, Inc.
http://www.dreamscopes.com
610 - 365 - 2833



At 02:27 PM 12/26/2005, you wrote:
>Polaraligned wrote:
>
> > Holding 1/10 wave or better is the priority and I know that the
> > edges are going to fade from this value.
>
>Pardon me for being blunt, but why the emphasis on surface accuracy for
>an instrument to be used at prime focus with a ccd camera?  Your
>resolution is going to be nowhere near diffraction limited, instead, it
>will be pixel size limited.  I'll bet, a calculation would show you can
>tolerate wavefront errors that would horrify a planetary or double star
>observer and still produce ccd images not even measureably below
>"perfect" quality.
>
>Maybe save some money by putting looser specs on that huge diagonal and
>put the money into a quick change arrangement on the secondary mount, so
>you can switch to a smaller, higher quality diagonal for visual use.
>
>Mark Holm
>mdholm@teerama.com

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