Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Stargazing Building Telescope Signting Laser

  1. Jan 30, 2010 #1
    Hello! I recently purchased a basic 6-inch Equatorial Reflector telescope. I bought it because I loved doing astronomy with large binoculars, and I assumed the next step was a small reflector telescope.

    However, I find myself barely using the new scope because the bulky Equatorial mount is very difficult to accurately align with Polaris, and so when I use it I loosen the joints and treat it like a dobsonian mount.

    This naturally requires me to do a lot of re-aiming and adjusting as a I view, which makes it frustrating to use because the sighting scope is terrible.

    When I worked with binoculars, I often used a green laser pointer to point out an object, and then I found the beam in the binoculars. I would like to do something similar with the telescope, except I want to mount the laser on the body of the scope in such a way that it always points to the center of the field of view.

    I am using a basic push-button laser, and I have no idea how to mount it such that it points with such precision. Does anyone have any experience or suggestions regarding how I should do this? I need to be able to adjust the pan and tilt of the laser easily.

    Thank you very much!
  2. jcsd
  3. Jan 31, 2010 #2
    Last edited by a moderator: May 4, 2017
  4. Jan 31, 2010 #3


    User Avatar
    Science Advisor
    Gold Member

    Lock your mount at your latitude and manhandle the mount north. Locate an object of known declination using your setting circles. Adjust mount to match that declination. It wont be perfect, but, you will almost always have object you are trying to find within your field of view.
  5. Feb 1, 2010 #4


    User Avatar

    Staff: Mentor

    Aligning an equatorial isn't that bad - since it is a manual mount, the accuracy isn't critical. Here's what you do:

    1. Your elevation/latitude axis should have markings for your latitude. Set it and forget it (you only do this once).
    2. Set up your telescope and tripod to point roughly north.
    3. Swing the counterweights to point toward the ground - your telescope will be directly above.
    4. Set your declination axis to 90 degrees (again, it should have markings). This will point the telescope parallel to the polar axis. In other words....
    5. Your telescope should now be pointing at Polaris. If it isn't, pick the whole thing up and rotate it until it does. If you want to make a fine adjustment to the elevation axis, now is the time.

    This procedure should get you within a degree or two of the north pole - good enough for manual, visual observing.

    After that, you just unlock the dec and ra axes and swing it wherever you want it.
  6. Feb 3, 2010 #5
    I agree with earlier posts- spring for a $35 Telrad. Telrads are simple to use, preserve your night vision, and provide accurate sighting.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook