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Stargazing Need Help - Learning to use a telescope!

  1. Sep 23, 2008 #1
    2 or 3 years ago we bought my father a telescope for his brithday, and ever since it has been a piece of 'art' in my house. I thought i'd put it to use, i have an interest in astronomy and now i really want to learn how to use this.

    the telescope is a Bushnell 675x5" Reflector Telescope, link below for more details.


    I've fiddled with it a few tiems and have brought it out to try it out and i am really having trouble. I set in either the 4mm or 20mm eye piece, and i see nothing but pitch black through them after searching for a few minutes. I try over and over again and see nothing but pitch black. (no, i didn't leave a cap on). I'd think that with a telescope, it should not be very hard to find some viewable light?

    so, any suggestions?
  2. jcsd
  3. Sep 23, 2008 #2


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    Welcome to PF....

    To see some visible light, you need to point it at something! What are you pointing it at and how do you know you have it in the field of view of the telescope? Hint: take the scope out during the day and point it at a distant object, focus it, and align the finderscope.

    Next, the larger the number on the eyepiece, the lower the magnification. Lower=brighter and larger field of view (easier to find things).

    Next, since the moon isn't up right now, the first object you should look at is Jupiter. It is by far the brightest object in the southwestern sky right after sunset (you can't miss it). Once you get it in focus with your 20mm eyepiece, you'll see up to 4 moons in a row and horizontal stripes. Then try the 4mm....

    Btw, that's a pretty good starter scope, but because it is an equatorial mount, it takes a little effort to set up correctly, though once you do, it is a good novice mount. You'll want to read the manual.
  4. Sep 24, 2008 #3


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    If you are looking at stars and the focus is waaayy off you may not see anything at all. Viewing a distant street lamp will get you close enough with the focus to see something... If you use it during the day as Russ suggests, leave the focus at the same position when you start at night.
  5. Sep 24, 2008 #4


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    Welcome to PF!

    Hi Shilly! Welcome to PF! :smile:

    It may have got damaged, or out of alignment, in storage.

    hmm … :rolleyes:

    first, look through the open end of the telescope … can you see your own reflection, with the secondary mirror in the way?

    then shine a torch into the eye piece, while still looking through the open end … can you see where the light is going? it should bounce off the secondary and then the primary and come straight at you without hitting the side of the tube

    … can't think of anything else :smile:
  6. Sep 24, 2008 #5


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    I am with Chemisttree on this one, street lamps are great as a starting point.

    Or at least that's what I did on many occasions :biggrin:
  7. Sep 25, 2008 #6


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    Re: Welcome to PF!

    If you're an American, torch means flashlight. Just want to make sure the OP is not getting out a plumbers's torch, or other flame-producing device :)
  8. Sep 25, 2008 #7


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    oops! :redface:

    I must mind my flaming language! :rolleyes:
  9. Sep 25, 2008 #8
    Perhaps the mirror is out of alignment and is not pointing down the centerline of the tube?
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