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Trouble Focusing - 7" Mak-Cass (generic mfr)

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Posted (edited)

First Timer on Stargazers.

Using a generic Max-Cass telescope, primarily for lunar viewing.  I have had good success with a photo mounted DSLR.  Recently, just using the eyepieces (including a Barlow), found I cannot get  it to focus through either either the primary eye piece or  alternate 90 deg. eyepiece.  I tend to see more reflection of my own eyeball and floaters.  Can't get nearly the image I obtain with  the camera attached. What part of the telescope is likely the problem.  Since the DSLR still relies on the telescope focusing knob, Where do I start?

Could a jolt have caused a focusing failure, mis-alignment? Closest shop for me is Skies Unlimited in Pottstown, PA.

Thanks in advance. If  post should be elsewhere, please advise.

Edited by gmanoug

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Have you tried focusing it during the daytime on a distant object?  Have you twirled the focuser knob all the way from one end of travel to the other?  If you can get your DSLR to come to focus consistently, remove the DSLR and replace it with an eyepiece (even if just handheld) with its shoulder in approximately the same position as the camera's sensor.  You should be able to move the eyepiece in and out a bit and get a focused image as well for it without touching the telescope's focuser knob.  If you can, that's one possible way to use the scope, though it may negate the use of a diagonal and require an extension tube of the proper length.  I'm concerned that your moveable mirror isn't moving properly to bring the telescope to focus.  Hopefully, that's not it.

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