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Stargazing Upgrading my telescope, need advice.

  1. Jul 15, 2011 #1
    For some years I have had an orion skyquest 4.5 inch reflecting telescope that I received as a gift some years ago. I have recently gotten back into astronomy and have discovered that my current telescope isn't quite as powerful as I would like.

    Does anyone know what size mirror would be appropriate for viewing deep sky objects (galaxies, nebulas) with some level of detail, my current telescope can only let me see a blur in the shape of the galaxy and then only on the closest galaxies, and I am hoping to upgrade to something with much more detail.
  2. jcsd
  3. Jul 15, 2011 #2


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    I believe at least a 6 in scope would be your best choice. Overall bigger is better, but it really depends on how much you are willing to spend. You can get a 10 inch Newtonian on a Dobson mount for a couple hundred, while my 10 inch Cass-Newtonian on its computer controlled equitorial mount was $1300. And I can't even see any galaxies other than the core of Andromeda unless I use my imager. But I am in a light polluted area, so your area might be different.

    A 6 inch scope will have about 80%-90% more light gathering than your 4.5 inch one, so that already is a huge improvement.
  4. Jul 15, 2011 #3
    I live in the country which probably explains the difference. Are there any telescopes between 6-10 inches with motorized mounts (just compensating for the rotation of the earth) in the range of 400-500$, or is that more expensive.
  5. Jul 15, 2011 #4


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    Sure. Just head on over to telescopes.com and have a look there. You should be able to find something. I got a 5.1 inch Meade on a computer control Alt-Az mount for about 250 bucks.
  6. Jul 16, 2011 #5


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    An 8" primary is the best price point for most people. Anything bigger is a headache and anything smaller leaves you feeling inadequate. Don't get me wrong, I love big tubes, but, they are heavy and need monster mounts - making a good rig expensive. A decent goto mount for a 10+ tube costs more than the tube. The factory mounts that come with mass produced 10"+ tubes are inadequate, IMO.
  7. Jul 16, 2011 #6
    Thank you guys, I think I am going for an 8 inch and maybe a 10 inch if I can find a cheap one.
  8. Jul 17, 2011 #7


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    Good luck! Also, just be aware of what you'll be expecting to see. Don't expect the kind of full color images you'll see online -- the only way to get these is to do precise astrophotography, which is an art unto itself. Certainly there are many deep sky objects which are beautiful to look at with the good old fashioned eyeball, but long exposure photographs really bring out most of the cool features.
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