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Old 19-04-2013, 06:37 PM
04Stefan07 (Stefan)
Make it so! - Capt.Picard

04Stefan07 is offline
 
Join Date: Jan 2012
Location: Melbourne
Posts: 1,982
Quote:
Originally Posted by Jason D View Post
That illustration in your link is mine (just check my avatar). The secondary mirror silhouette (shadow) will look shifted as the illustration shows for all reflectors though the shift will be more prominent for faster scopes.

If you are interested in knowing the reason, it is because you see the secondary from two difference perspectives. The first perspective is from the focuser side looking at the secondary mirror directly – the secondary will look concentric. The second perspective is from a virtual point behind the primary mirror – the secondary will look shifted. Check attachments.

You can never have the secondary mirror look concentric from both perspectives -- only from one.

I am also including a photo from my collimated scope.

Jason
Third image is what I was after!!

Makes much more sense now why it looks not centered.

It was right all along, thanks!!!
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