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Old 23-03-2008, 11:26 PM
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skwinty (Steve)
E pur si muove

skwinty is offline
 
Join Date: Dec 2007
Location: Cape Town
Posts: 494
Quote:
Originally Posted by avandonk View Post
The elongation in the top right corner is due to a mixture of vignetting field curvature and slight error in the collimation. Full frame is very difficult to get everything perfect to the corners especially with fast Newtonians.

Bert
Hi Bert
I was referring to the centre of the image.
With my f/5 Newtonian 1520mm focal length I use a Coma corrector which I find works a treat with outer field coma distortion.
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