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B Double image in reflector telescope

  1. Apr 18, 2016 #1
    Complete reflector novice here. Just got a reflector (using refractor before). I had no problems doing astrophotography with my refractor however with the reflector I get double images.

    Why is this so? Is this a collmination problem? It's not the camera because there's double images when I look through myself.

    Thanks in advance
     

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  3. Apr 18, 2016 #2

    Borg

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    Just a guess but, it looks like you're trying to focus on something that is too close to your telescope. How far away is the object and what is the focal length of the telescope?
     
  4. Apr 18, 2016 #3
    It has a 1400mm focal length. Here is also a picture of the Moon which appears to have the same problem. The tree is just across a small parking lot.
     

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  5. Apr 18, 2016 #4

    Borg

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  6. Apr 18, 2016 #5

    russ_watters

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    Borg is correct.

    The moon definitely doesn't have the same problem. It may not be quite perfectly in focus, but it is close.
     
  7. Apr 18, 2016 #6
    Is it possible I have a bad quality mirror? My refractor had half the aperture and gave me way better detail. Although yeah it could be the alignment.
     
  8. Apr 18, 2016 #7

    russ_watters

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    Based on the pictures you posted, I find it very unlikely that you have a bad quality mirror. But you may want to look into a "star test collimation".
     
  9. Apr 18, 2016 #8

    Borg

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    Here's a link on collimation of the telescope with some good graphics.
     
  10. Apr 18, 2016 #9
    Thanks guys, I'm gonna change the cam first too and see if that helps. I was using my iphone (8 MP) but this cam is only 3MP, so I'm gonna print out a support and see what happens, and align the mirrors too.
     
  11. Apr 18, 2016 #10

    russ_watters

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    Does it look better with your eye? I wouldn't trust an iPhone with this task. FYI, none of the pictures on my website were taken at more than 2mp.
     
  12. Apr 18, 2016 #11
    Wow your images are very impressive! Especially being able to see some color on Europa.
     
  13. Apr 18, 2016 #12

    russ_watters

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    Thanks! My recommendation if you're on a budget is to get a decent webcam, remove the lens and attach it without an eyepiece to the end of the telescope. That's called "prime focus photography". Then take uncompressed videos and use stacking software like Registax (free) to process it. That's how you get the ultra-clear photos of the moon and defeat atmospheric distortion.
     
  14. Apr 18, 2016 #13
    Sweet. I managed to hopefully fix the double image problem by just focusing the telescope right. I took off the lens on the cam that came with the telescope and attached it to a 10mm eyepiece, the magnification looks way better.

    Would you have any advice on how to set up tracking for a GPS telescope. I haven't found any good tutorials. I did the Moon alignment test and it didn't work. I see a sign on my telescope that says south, so am I supposed to point the telescope south before the test? Thanks in advance!
     
  15. Apr 18, 2016 #14

    russ_watters

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    All telescopes are different: what is the make/model?
     
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