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Old 09-12-2007, 07:01 PM
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astropolak (Joe)
Never, ever give up hope

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Join Date: Nov 2005
Location: Sydney
Posts: 244
Thank you Mark and Frontier (Daniel) you both have given us very informed and totally satisfying responses.

Mark
There is substantial light path length in Newtonians as well as there is a need for diagonal and focuser as well as the need to have steeper light cone at F4-F6. In my limited understanding of the optics this would require larger secondary than normal as well as something like 3" aperture focuser...
All this to fully illuminate a 24 Pan with field stop of ~ 27mm...

RGDS Joe
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