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I choose to post this question on the physics exchange seeing there would be a bigger audience for answers than the astronomy exchange still in BETA. But i'm looking to buy a telescope and was wondering what i could see with a 114mm Aperture 675x Zoom Telescope? The type of things would be interested in would be our planets their moons, comets hopefully and even very bright galaxy's if possible.

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This really doesn't belong here, but I will answer anyway, because I don't like to see people being ripped off by the kind of cheap toy telescope that you seem to be referring to (at least that's what showed up when I entered your description into google). The sad reality is, that you can't see much of interest beyond the moon, and even that is, IMHO more enjoyable with cheap binoculars.

I bought one of these toys a month ago for \$10 at a thrift store to get a first hand experience of the "quality". To be honest with you, I was disappointed even for \$10.

The only useful eyepiece that came with the "instrument" was the 20mm. Given the focal length of the primary mirror of approx. 600-800mm, the effective magnifications is approx. 30-40. That's it. Even the 12mm eyepiece was, in my opinion useless and I couldn't properly focus the 9mm and shorter ones, at all. I never tried the 2x focal length extender... it would be a waste of time. So forget about 625 times magnification... that is more than beyond the useful range of even the best instrument with 114mm aperture. Anything above 100 times magnification is complete nonsense, not to mention that you couldn't find what you are looking for without a precision mount to begin with.

Now, since I also own other optical instruments (for professionals), I matched a low quality 25mm wide angle microscope eyepiece to the instrument (that's approx. a $25 investment, if you don't have one of these laying around). This made the telescope both more enjoyable and more useful. The moon appears in reasonable clarity now and I actually like pulling my Frankenstein out of the garage to look at it for a couple of minutes occasionally. As for a real telescope eyepiece, they won't fit, because the plastic eyepieces on this toy are approx. 1" in diameter, while the smaller amateur eyepieces are 1.25", if I am not mistaken. At the very least you would need an adapter.

Mars is not resolved, except as a tiny disk, and the coma is horrible, even after adjusting the primary mirror, which was screwed in so tightly, that one could see it bending visibly. I loosened the mirror mount but didn't take the time to adjust the optical path perfectly, since the primary mirror has visible coating problems and scratches around the rim, so I figure that it's nowhere near the right shape, anyway.

Saturn shows the slightest hint of a girdle, again barely distinguishable from the instrument's optical errors. I didn't have a chance to look at Venus, yet, but I don't expect to see much more than a hint of its phase, either. Jupiter's moons should be visible, but they can be seen with binoculars and it's easy enough to take a good photo of them with a 150mm or so zoom lens on a low end DSLR, so you don't really need a telescope for that.

The other day I looked at the Andromeda galaxy. Even though I know how to find it with naked eyes, it took me about half an hour to get it into the view of the instrument, since the finder scope is too dim to see it in there. You are basically tapping around blindly across the sky... until you are lucky to hit what you are looking for, assuming that it has distinguishable features. Well, Andromeda looks like a mere wisp, even in my wide angle Frankenstein eyepiece (I wouldn't expect to see it, at all, with the eyepieces that came with the scope). All one can see is the galactic core, there is no hint of the spiral galaxy structure. For comparison, I can clearly see the spiral galaxy in digital camera images using a simple tripod, a 50mm lens and 10-30 seconds of exposure time.

A very motivated amateur astronomer might be willing to look for things that are less luminous than Andromeda, but I think that Andromeda will be the one and only deep space object I will ever see in my toy, it's just too hard.

So where does that leave you? If you listen to me and everybody else who ever wrote a basically indistinguishable critique of "toy catalog telescopes", it will leave you about \$79-99 richer. If you want a telescope badly, the cheapest ones worth any money are probably 8" Dobsonian "light buckets" for approx. \$400. They are just what the name implies: an 8" primary in the lowest grade of mechanical mount that makes them useable for magnifications in the range of 30-100, or so. They are bright, have a wide field of view, and you can learn how to navigate the sky with them.

If you want to trade the size of the primary against the mount, you can go with a smaller aperture and a higher quality mount. Meade sella "better" versions of the aforementioned toy telescopes for around \$200, but I wouldn't spend that money, either, but save, at least \$400 for the next level up from there.

Even better, if you can find an amateur astronomy club, you may be able to look trough instruments in the \$10k price range that are owned by your new club friends. That will give you a much better idea of what can and can not be done with visual observing, even for a lot of money. If you can stand the disappointment, that Andromeda doesn't look nearly as magnificent as trough the focal plane array of the Hubble space telescope, then amateur astronomy may be for you!

Good luck!

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  • $\begingroup$ Thankyou for the detailed response. Just for reference this was the telescope i was looking at: ebay.com.au/itm/… But i might second guess that now. But from the information from the ebay description would this still be classed as a very toyish telescope? Like no-usable $\endgroup$ – Hatmix5 Sep 6 '14 at 8:39
  • $\begingroup$ Sorry, but the toy I am describing is virtually identical to what they are selling in that ebay listing. Please save your money. A telescope is a non-trivial optical and mechanical instrument, the mount is just as important as the optics for it to be useful. To make one that has even the minimal specs needed for amateur astronomy costs a non-trivial amount of money, even with modern mass manufacturing techniques. I would say that \$400 (US) is really the minimum that one should be willing to spend on a telescope. $\endgroup$ – CuriousOne Sep 6 '14 at 8:44
  • $\begingroup$ Also for reference i was looking into this telescope as well: ebay.com.au/itm/… $\endgroup$ – Hatmix5 Sep 6 '14 at 9:05
  • $\begingroup$ With the Celestron you are getting, at least in principle, a lot closer to a useful instrument. I have never owned one of those before, so I am not going to critique it and there are a few detailed descriptions of it on the internet. $\endgroup$ – CuriousOne Sep 6 '14 at 13:58
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I see this type of questions/answers everywhere, but I have a bit different view on it. It's like asking "should I buy a bike with training wheels". Of course all experienced guys out there would say no, it's a waste of money and you'll throw them away after two weeks.

But I believe that some lessons are worth 50 dollars. The point is, if you're just a beginner and have no idea what astronomy is, but you feel like you'd enjoy looking at the stars, do yourself a favor. Buy a 114mm reflector off Craigslist. It's not difficult to find cheap Meade or Celestron models there for \$40 - \$50. Don't expect to see much, but the experience will probably result in one of two thoughts: "I don't like it, I want better" or "I don't like it and I don't want to deal with this nonsense".

If the latter is the case, the only hope, as others mentioned would be to go to a star party and try to look through a quality scope (if no problem,this could actually be the first step). But if it's the thought you're getting, I would probably not recommend spending \$400 on your own scope "to try things out", because most likely it would end up in the attic.

However, if you're excited about the potential, and the whole experience feels like your thing, you now are ready to upgrade. And as the first step I'd recommend getting one medium power Plossl eyepiece - it's a gigantic step up for about \$20, and you'll be able to use it in the future with better instrument. Then you can start saving for a "real" telecope.

In either case I believe for $50 you learned a lesson which gave you first hand experience as the answer, as opposed to some post on the Internet.

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    $\begingroup$ You can buy decent 8x42 or 10x50 binoculars for \$50 from most of the made-in-china sites that will do better than a \$200 telescope - especially if you add a tripod. And you will also have a pair of binoculars. $\endgroup$ – Martin Beckett Nov 11 '14 at 20:30
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The one you are looking to buy is not going to do well at all. After a lot of research I bought the celestron powerseeker 114eq. It does quite well and should provide excellent viewing using better eyepieces. I had to spend only $154. Granted it's not the best mount and the eyepieces but it should serve you well until you become good at skywatching.

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