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Stargazing Trying to pick out a telescope (Need help)

  1. Sep 26, 2010 #1
    I'm an Astronomy major with an emphasis in Astrophysics. So my career is going to be in studying the sky and deep space objects.

    I have owned several telescopes in the past but never really learned how to use an equatorial mount (I was about about 8 years old at the time and didn't have the attention span to learn such things). But now that I know how to align and utilize the different types of mounts, I've figured it's about darn time for me to get some optics.

    I've been looking around on Craigslist and found a 6 inch Dobsonian, used, for $200.

    http://phoenix.craigslist.org/nph/for/1968592871.html [Broken]

    I also found a couple Schmidt-Cassegrain 8 inch telescopes for between $500 and $700 dollars

    http://phoenix.craigslist.org/wvl/pho/1963150052.html [Broken]

    http://phoenix.craigslist.org/evl/for/1896472116.html [Broken]


    I will be using the telescope to view both stellar objects, galactic objects, and intergalactic objects. So I need something that will cater to a wide range of observations.

    I'm trying to stay on a limited budget (even though I have the money to buy a $1000+ telescope). I know that light buckets are going to give me brighter observations than a similarly sized SC. And I know all about the calculated advantage of using an 8 inch mirror over a 6 inch mirror.

    But I don't really know what the real world, observable, difference would be when you have 180% more light gathering capability. And will it be significantly more difficult to locate deep space objects with an alt-azimuth mount as compared to a equatorial mount?
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Sep 26, 2010 #2
    There is also this 8 inch SC located in Tucson (about 120 miles from me)...

    http://tucson.craigslist.org/spo/1973316803.html [Broken]
    Last edited by a moderator: May 4, 2017
  4. Sep 26, 2010 #3
    And here is a 6 inch Celestron refractor telescope for $575

    http://tucson.craigslist.org/pho/1935287125.html [Broken]

    That's pretty interesting.
    Last edited by a moderator: May 4, 2017
  5. Sep 26, 2010 #4
    It will not be any easier to locate objects with an equatorial mount. Equatorial mounts are necessary for photography or if you have a motorized one with go to setup.

    For observing there is no need for an equatorial mount. I'm not sure what you mean about the real world difference of more aperture. Things will be brighter and easier to see. If you want any chance at locating much outside of the messier catalog, it wouldn't hurt to have something bigger than 8 inches.

    Personally I would recommend the largest dobsonian you can afford, which has decent optics and which is portable enough that it doesn't prevent you from using it.
  6. Sep 26, 2010 #5
    http://www.meade.com/product_pages/lightbridge/lightbridge_10/lightbridge_10.php [Broken]

    Dunno much about refractors, usually a 6 inch is pretty expensive though. That one you posted might be a steal (or maybe not, need to do some research).
    Last edited by a moderator: May 4, 2017
  7. Sep 26, 2010 #6
    Well, if I want to track objects, it would be nice to have a mount that can be fixed on the polar axis so I only have to move one axis. Plus it would be easier to access remote objects. Granted, it would be slightly more tedious to move an equatorial mount to many different places in the sky.
    Last edited: Sep 27, 2010
  8. Sep 26, 2010 #7
    It's about half the price of the same model with a computer controlled locater.
    Last edited by a moderator: May 4, 2017
  9. Sep 27, 2010 #8


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    I like both 8" SC's. The short tube and light weight are a big plus. They probably wont last long at those prices.
  10. Sep 28, 2010 #9
    It depends what you want to do. If you're the lazy type who just wants to plop down the scope and push a button, Orion makes a line of computerized dobsonians which are nice scopes and will go-to objects for you.

    If you want to learn the sky for yourself, a regular dobson is a good choice but an EQ mount is much nicer for star-hopping than an alt-azimuth mount.

    If I had to start all over, I'd go with a Newtonian reflector and a good EQ mount.
  11. Sep 28, 2010 #10
    If I can add another related question. I too am looking for a good scope and am drawn to the 8" Celestrons or Orions on first glance. These are priced right for a good beginner, but I have been informally advised that the 10" are better. No doubt; also more expensive.

    Also, I am interested in doing photography with whatever I buy. I understand that Dobs are not recommended for that purpose (which is a shame, cause I had an offer of a really good deal for a 10" Dob). Is this true?

    Could some of you who are experienced with this weigh in on the various merits? It will be much appreciated.
  12. Sep 28, 2010 #11
    It's really a matter of preference, which you won't really know until you've had your own scope for a while. I started out with a 6" orion dob. Now I want one of these http://www.obsessiontelescopes.com/telescopes/18_UC/index.html [Broken] :biggrin:
    Last edited by a moderator: May 4, 2017
  13. Sep 28, 2010 #12
    You can do photography with a computerized dobson that comes equipped with automatic tracking, but I don't know of any in the 8-12" range that come with this feature. If you upgrade to the 16-20" range then this feature is more common, but these are very expensive scopes.

    You really want an EQ mount to do photography with. Schmidt Cassegrain scopes are well suited for this, but a Newtonian reflector may be a cheaper alternative.

    edit - A bit of advice, start out with a cheap scope until you decide if the hobby is really for you. Astrophotography is a very expensive hobby and it's easy to sink upwards of $6000 into it just to get you started.
  14. Sep 28, 2010 #13
    This is a good point. Lots of people will try to steer you away from photography as a beginner, and not without good reason.
  15. Sep 28, 2010 #14
    There is a guy who posts on this board who does very nice astrophotography. A quick glance at his set up will show you how involved it can get. http://www.russsscope.net/
    (assuming he doesn't mind me saying so, it is linked from his profile)
  16. Sep 28, 2010 #15


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    A meade pro II dsi ccd runs about $400 and takes nice pictures. You can also use an ordinary digital camera, although less sensitive than a CCD. With a CCD, you dont need a clock drive for exposure times of a few seconds - more than enough time to photograph the brighter Messier objects. A clock driven altazimuth mount is as good as an equatorial mount for exposure times up to a few minutes. See http://www.meade.com/dsi/gallery/gallery.html [Broken] for some pics using an 8" SC on altazimuth mount with 30 second exposures.
    Last edited by a moderator: May 4, 2017
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