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Anyone own a Celestron 11'' schmidt cassegrain?

  1. Mar 15, 2007 #1
    Hi there,

    I am using a celestron C11. But I really need some help with aligning it up through auto 3 star align.

    The counter weight bar pointing approximately due north with the index marks aligned and locked.

    I aligned the eyepiece with the finderscope on polaris.

    I set the exact time and date, longitude and latitude for Dublin where I live.

    I then selected auto three star alignment method.

    I selected betelgeuse as my first alignment star, and that star was in the south east but when i clicked enter on it the telescope slewed down towards the western horizon.

    What am I doing wrong??
  2. jcsd
  3. Mar 15, 2007 #2


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    Staff: Mentor

    As a matter of fact, I do.... :biggrin:

    However, I'm guessing yours is mounted on a Celestron CG-5 mount? Mine is on an Orion mount. But, maybe I can help...

    I don't understand what you mean by this:
    Since the counterweight shaft is the dec axis, it is always perpendicular to the polar axis. The hole through the center of the mount (if you don't have a polar alignment scope in it) should point at Polaris. Usually, the home position has the counerweight shaft pointed down and the scope pointed north (like the picture on the front of the manual).

    Other things to check:
    -Time Zone
    -E vs W longitude
    Last edited: Mar 15, 2007
  4. Mar 15, 2007 #3
    Yes its on a CG-5 mount.
    I mean the counter weight bar is pointing down and the optical tube is pointing at polaris. And the index marks (the two pairs of triangles are aligned with each other).
  5. Mar 15, 2007 #4


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    Staff: Mentor

    Another possibility - Beetlegeuse is due south at sunset right now. Please don't be insulted, but you aren't mixing it up with Procyon, are you (which is in the southeast)?

    The telescope and counterweights should be turning roughly parallel to the ground with the scope rotating something like 140 degrees around the dec axis. Is it actually pointed down at the ground or just lower and further south than you think it should?
  6. Mar 16, 2007 #5
    No betelgeuse is the red supergiant star situated diagonally to rigel. And it was in the south when was I trying to align it.

    The image I have attached indicates how the scope is aligned initially when pointing at polaris in the north. Is that right?
    The tube points to the west on the horizon.

    Attached Files:

    Last edited: Mar 16, 2007
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