3
$\begingroup$

I am a beginner when it comes to telescopes and have been doing research online for a week with which one to buy. At the moment I’m interested in a pre-owned telescope. My priority is planets but also gaze to Andromeda if possible. I read that refractives are better for planets but I’m not finding them in my area maybe. Here are some that are available in my area:

  1. Celestron 114LCM (114 mm aperture, f/8.77 Newtonian) Computerised: I like that it has a motor that can automatically pin point to an object so will help me. But it’s a bit easy to locate the Moon, Jupiter and Saturn so do I even need it?
  2. Celestron Astromaster 130 EQ (114 mm aperture (not 130) f/8.7 Newtonian): it has better clarity I guess? But problem is, it is all manual and bulky. Means I have to adjust it every time I have to watch something new or to show to people. Also, it comes with heavy weight to might be difficult to carry around?
  3. Celestron Star Sense Explorer LT 127AZ (127 mm aperture, f/7.87 Newtonian)

I'm not asking a "shopping question" so don't tell me what to buy. But I would like some input about what criteria I can use to choose between these; are they all basically equivalent? Are there some types of features (in this class of telescope) that may be more important than others from the point of view of a beginning observer?

$\endgroup$
11
  • 1
    $\begingroup$ Product recommendations don't really work well. Generally you pay for what you get. We can't answer questions like "Do I need it" - obviously. You have to read the product descriptions and make a decision. If there is something in the product descriptions that you don't understand (like "what does 130 mean?" or "Why does it come with a heavy weight") Those questions can be answered. $\endgroup$
    – James K
    Nov 27, 2022 at 11:08
  • 2
    $\begingroup$ @uhoh I think you're edits makes it seem the OP knows more about telescopes than they do. When I saw the aperture, f ratio, and type, I was pretty convinced they had already learned most of what they needed to. $\endgroup$ Nov 27, 2022 at 15:31
  • 2
    $\begingroup$ Any of the three listed are descent telescopes. The best advice before buying a telescope is to attend a star party by a local club and look through different scopes. If you're planning to buy something before xmas, that might not be possible. I recently gave a "How to Buy A Telescope" talk for our local club, I cut out everything I didn't think was absolutely necessary, and it still took about an hour, followed by some telescope time. So it's not really feasible to summarize all of the key points in an answer here. There are many Youtube videos on the topic, I recommend you start there. $\endgroup$ Nov 27, 2022 at 15:39
  • 2
    $\begingroup$ Be aware that the high focal length/short tube reflectors like the 114LCM are 'bird jones' reflectors. These telescopes use a spherical instead of parabolic mirror that's cheaper to make, and then they add a corrector lens to the focusing tube to make it work. These telescopes are very hard to collimate, which Newtonian reflectors need on a fairly regular basis. Also, a long focal length telescope on a cheap mount is a recipe for frustration. $\endgroup$
    – Dan Hanson
    Nov 27, 2022 at 20:36
  • 2
    $\begingroup$ You can tell a Bird-Jones reflector from a standard one by looking at the ratio of focal length to tube length. Bird-Jones designs have much shorter tubes. For example, the 130EQ you mentioned has a 630" focal length, and a tube length of 610mm - close to the same, so not Bird Jones (The 130 EQ is an F/5 telescope, not F/8.7, and a 130mm primary, not 114). The 114 LCM on the other hand, has a focal length of 1000mm, and a tube length of roughly 500mm. It is a Bird-Jones design. This will be true of all 'Newtonian Reflectors'. If the focal length is 2X the tube length, it's Bird-Jones. $\endgroup$
    – Dan Hanson
    Nov 27, 2022 at 20:48

0

Browse other questions tagged .