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Jupiter (clearer) Nov 5th 2023 w/Mewlon 180c

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My First C8 - a couple questions

Started by meadfish, 02/25/2008 03:29AM
Posted 02/25/2008 03:29AM | Edited 02/26/2008 01:40AM Opening Post
Hi all, I recently bought a used Celestar C8. It was not abused but perhaps a bit neglected. I see some smudges etc on the front corrector. I've seen some methods for cleaning but wondering how risky it is. I don't want to make it worse. also, the focus knob seems to catch once per revolution in the same spot. Is this normal? Is it a common problem? is it something that me a novice can fix?

any help greatly appreciated. also any tips that will help me get the most out of it smile

Thanks in advance, Jerry Mead
Posted 02/26/2008 03:26PM #1
Jerry Mead said:

Hi all, I recently bought a used Celestar C8. It was not abused but perhaps a bit neglected. I see some smudges etc on the front corrector. I've seen some methods for cleaning but wondering how risky it is. I don't want to make it worse. also, the focus knob seems to catch once per revolution in the same spot. Is this normal? Is it a common problem? is it something that me a novice can fix?

any help greatly appreciated. also any tips that will help me get the most out of it smile

Thanks in advance, Jerry Mead

A "smudge" can be anything from a barely detectable something to a splotch of bird poop. If it's more the former, leave it alone. If the latter, correctors can be safely cleaned. Just clean as you would a good camera lens.

As for the focuser, my adive is DO NOT go tearing into the OTA without help. Try racking the mirror to both end of focus a few times and see if that helps. If not, it might be best to "call Celestron."

8)

Uncle Rod

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Posted 02/28/2008 06:26AM | Edited 02/28/2008 06:29AM #2
Thanks all for the replies. I think I can be content with the corrector since it appears to be light smudging and not something major like bird dung. The focus issue though is annoying, I wasn't sure if that was common to these scopes. I looked at that article and may endeavor it one rainy day. wink What type of grease would be recommended if I get that far?

Clear skies to all,

Jerry