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Stargazing Saving the telescope with damaged optics

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  1. Aug 22, 2013 #1
    I have a Celestron NexStar 4SE, I damaged the optics. Is there a company who just sells the telescope without the computerized mount?
     
  2. jcsd
  3. Aug 22, 2013 #2
    Also with that in mind, can this telescope be used to take pictures of planets
     
  4. Aug 22, 2013 #3

    chemisttree

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    Yes… and yes.
     
  5. Aug 22, 2013 #4

    Drakkith

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    Sure, just don't expect any amazing pictures. With only 4 inches of aperture your resolution is quite limited.
     
  6. Aug 23, 2013 #5
    Does anyone know any specific stores that sell just the 4SE telescope it self? excluding stand and computer mount.
     
  7. Aug 23, 2013 #6

    Drakkith

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    Sorry, I looked around a little bit online but couldn't find any place that sold just the OTA.
    How badly damaged are the optics?
     
  8. Aug 23, 2013 #7
    Check local astronomy clubs, that is a very common telescope and usually its the mount that breaks, i'm sure theres a ton of OTA lying around.

    What exactly did you do to the optics that you think they're busted?
     
  9. Aug 23, 2013 #8
    I left it exposed to the Arizona heat for a few months
     
  10. Aug 23, 2013 #9

    Drakkith

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    You anywhere close to Tucson?
     
  11. Aug 23, 2013 #10
    And? What happened as a a result of that? The optics are made of glass and aluminum - they aren't going to be damaged from normal temperatures, even on a hot day.
     
  12. Aug 23, 2013 #11
    the lenses are coated, does the heat damage the coating? I see spots when I view any object
     
  13. Aug 23, 2013 #12
    It was in Tucson
     
  14. Aug 23, 2013 #13

    Drakkith

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    Possibly, but I'm not sure. Are you certain it is the optics of the OTA (Optical Tube Assembly) and not the eyepiece that are damaged?

    Are you still in/near Tucson? If so, there are a few stores in town that might be able to help you.
     
  15. Aug 23, 2013 #14
    Celestron uses what they call "Starbright XLT" coatings for that model, which is a blend of MgF2, HfO2 and TiO2, all of which have melting points well above 1000 degrees Celsius - the coating is not going to be damaged by exposure to temperature in the 100-120 degree F range, which is probably the hottest it could have gotten.

    The lenses are probably just dirty, or your particular eye piece is damaged, or the telescope is out of collimation (though I don't see how this would cause spots). I suggest you find a local astronomy club who can teach you how to properly use and maintain your equipment, and can give you tips on cleaning the mirror or lenses if they need be.
     
  16. Aug 23, 2013 #15
    That's very interesting information. Thank you
     
  17. Aug 23, 2013 #16
    I don't live in Tucson anymore
     
  18. Aug 23, 2013 #17

    Drakkith

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    Honestly if you are seeing spots, and not just general blurriness, that suggests that it may be your eyepiece that is damaged. If the optics were damaged then it should lead to blurred images, not spots. Get a flashlight out and inspect the glass in the front of your telescope and the mirror at the back. See if you can find anything that looks out of place. If you can't, then I doubt your optics are damaged.
     
  19. Aug 24, 2013 #18

    Borek

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    For me spots suggest optics is not being destroyed, just dirty. But then my experience is very limited.
     
  20. Aug 24, 2013 #19

    chemisttree

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    And if you can see spots then the defect or dust is near the focal plane of the telescope. Could be an EP but it is more likely the diagonal. If a Mak-Cass is out of collimation it doesn't manifest as spots. I don't even know if a Mak can be easily collimated but I suppose it is possible. All of the surfaces are spherical so factory collimation is pretty robust and the secondary is glued to the corrector so there isn't an adjustment for it.

    Check your EP by observing a bright field (uniformly lit daytime image or the moon) and rotate the EP inside the barrel of the diagonal. If the spots move, it's your EP. If not then remove the diagonal and insert the EP directly into the rear of the OTA and see if they are still there. If you still see spots, you might have 'floaters'.
     
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