We have a Celestron 70AZ 70mm f/10 refractor that has been working perfectly. Our children knocked it over the other day, and now when we try to view the moon, it fills the lens as a giant, blurry ball of light. Have they knocked something loose? We tried adjusting the different focus knobs but I am worried it's messed up and I have zero clue how to fix this, diagnose it or even where to go to get it looked at.

  • $\begingroup$ Hi, without at least a picture or two, and a lot more information (loose parts rattling? eyepiece missing one lens?), remote diagnosis is basically impossible. About your only chance is to find a friend who's an astromomer and have them look at it. $\endgroup$ – Carl Witthoft Jun 18 '19 at 17:06
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    $\begingroup$ Welcome to Stack Exchange! It's possible that the problem is as simple as it now being really far out of focus. I'd say have a look during the day, point it at something far away (say 100 meters away or farther) and spend some time moving it to each of the the extremes of focus, using the lowest power eyepiece. Make sure there's no Barlow lens in place (not sure if you have one) Perhaps you've just lost track of where best focus is, working during the day looking horizontally might be easier than trying to focus on the Moon. $\endgroup$ – uhoh Jun 18 '19 at 17:29
  • $\begingroup$ Also, try a different eyepiece than the one that was in the telescope when it fell over. Give it a gentle shake, do you hear anything rattling around? Can you mention if there are any dents or bangs visible? If so, can you explain the locations? Could you also mention the numbers written on the two eyepieces? Are they f=20mm and f=10mm, or f=20mm and f=4mm? Thanks! $\endgroup$ – uhoh Jun 18 '19 at 17:30

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