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Old 01-03-2010, 08:29 PM
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Blue Skies (Jacquie)
It's about time

Blue Skies is offline
 
Join Date: Nov 2005
Location: Melbourne
Posts: 1,221
Hang on, hang on, its not 'wrong' that he can't see the clips. This will happen if the secondary is on the small side. "Well, why would anyone do that?" you might ask. If you are trying to minimise the impact of the secondary on your visual observing so that you can maximise the contrast - something you might want to aim for if you were a dedicated observer of the planets and were only using the centre of the field of view and not the outside.

The only fix that I know about is to get a bigger secondary, but with a small scope like that its probably not worth it. Moving it up the tube will only stuff up the collimation. You only need to move the secondary up if its not centralised under the focuser.

This is an interesting case as usually the makers will err on the larger side. Something I've noticed with modern short focal length scopes is the secondary is oversize. I'm wondering if this is an older scope?
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