Thread: [WITHDRAWN] Comet Catcher/Astrograph
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  #5  
Old 26-09-2012, 09:01 PM
Dennis
Dazzled by the Cosmos.

Dennis is offline 		 
Join Date: May 2005
Location: Brisbane
Posts: 11,820
Just guessing here, but if we do a quick calculation using 180mm focal length at an F:Ratio of F1.5 we derive an objective diameter of around 120mm, or around 4.7 inches in the old money.

Cheers

Dennis