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Old 07-09-2016, 09:01 AM
Dennis
Dazzled by the Cosmos.

Dennis is offline
 
Join Date: May 2005
Location: Brisbane
Posts: 11,786
I strongly suspect that those 2 long screws intruding in the light path will have a noticeable effect on the image in terms of producing diffraction pattern artefacts.

I can easily see such artefacts when I am collimating my ‘scope and I use a small Allen key to adjust the secondary. The diffraction pattern from the Allen key is clearly visible on my computer screen with a CCD camera in the eyepiece holder.

(The Allen key is of course attached to a small length of nylon fishing line so I don’t drop it onto the mirror).

Cheers

Dennis
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