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Please Help! I can't get my C-11 to focus

Started by dmcgregor43, 06/22/2016 08:06AM
Posted 06/22/2016 08:06AM Opening Post

Please help me figure out what I'm not seeing here. I have a Celestron C-11 on a CGEM mount. I had a sharply perfect picture with the scope originally, until I installed a set of Bob's knobs to replace the collimation screws. After installing the knobs I collimated the scope to the best of my knowledge using the planets and a few stars, but nothing has brought that sharp picture back. I've cleaned the collector plate a couple times too. I am in Chicago and would really appreciate any help in person or via comments.

Thank you
Posted 10/18/2016 04:44AM #1
Hi Don, you may have solved the issue already, my only comment if you have not is planets are not used to align a scopes optics only stars. Also in general you only adjust 2 of the 3 screws on the corrector (secondary mirror) to realign the optics.