Different Types Of Mounts In Beginner Telescopes Discussed

We live in a time of unprecedented telescope availability. Viewing the catalogs of yesteryear–the 50s, 60s, even as recently as the 90s–one learns the incredible expense associated with telescopes of the time. Telescopes with two-inch-wide achromatic objectives, mounted even on simple altaz forks, would be a severe investment. Nowadays we can find similar offerings for 50 or 100 bucks, and large commercial Dobsonian reflectors with apertures of 6 to 12 inches are becoming very affordable. There are more telescopes than ever for beginners, and the sad fact is that a great many of them are rubbish.

The “Department Store Refractor” is an archetype of a generally very poor telescope, essentially a toy sold to parents who don’t know better, usually with poor optics and poorer mounts. But this term, related to the more descriptive “Hobbykiller Telescope,” can also be applied to some big-name telescopes sold by Celestron, Meade, and Orion.

The truth is that a great many of these refractor telescopes are not horrible, optically. Most of them use glass achromatic (false-color-reducing) doublet lenses of long focal lengths and can produce some crisp images. The trouble is often in the accessories. Much ink has been spilled about the optical shortcomings of “hobbykiller telescopes,” but the actual objective lens is usually half-decent, if somewhat small. More important is the accessories, which tend to be low quality, and in the cheapest examples, they’re based on the deprecated 0.965” standard. Again though, much ink has been spilled about these accessories.

In these cases, even with telescopes using pretty poor accessories, the telescopes are still optically superior to what Galileo, Kepler, Messier, and Huygens had to play with, and each of them made some of the most interesting and important observations in astronomy.

For a cheap instrument, somewhat poor optics can be forgiven, up to a point. Much more important in determining whether a telescope will remain a useful and engaging observing instrument or will stay unused in the attic is the mount. A wobbly mount, one which refuses to hold steady, which drifts or drops or sags, which shakes if you look at it wrong: that is the real hobby killer, and it is all too common in beginner telescopes of all optical configurations.

How can we avoid hobbykiller mounts? The short answer is “Avoid any telescope on a tripod by default; get a Dobsonian.” You can of course find plenty of decent beginner telescopes on tripods, but the easiest way to avoid the worst ones is to steer clear of them. The long answer follows.

Types of Beginner Telescope Mounts

Let’s take a look at some of the mounts which are often shipped with beginner telescopes. The motions of a mount, that is, the axes through which they rotate, come in three main varieties:

  • Altitude/Azimuth (Altaz): These go up, down, and all around. The telescope swivels around 360 degrees of azimuth, all around the horizon, and its altitude axis allows you to view anything from the horizon to the zenith (top of the sky.) The trouble with these is the difficulty in pointing at objects within “Dobson’s Hole,” a region of the sky near the zenith where it becomes very difficult to point and track because the azimuth axis needs to do a lot more turning.
  • Equatorial (EQ): These telescopes are conceptually the same as tilting an altaz telescope so the azimuth axis points not straight up, but at the celestial poles. If you don’t immediately know what I mean by that, do not fret, but know that an EQ mount is likely not the best choice for you. Equatorial mounts are usually a lot more complicated to set up and use, but they have the distinct advantage that a single axis can be rotated to keep up with the rotation of the Earth.
  • Infinite Axis (Ball): Very rare these days, but very easy to use. These telescopes are mounted inside or atop a smooth ball, which rests in a cradle. Newton’s first reflecting telescope, and the infamous Edmund AstroScan, are examples of this sort of mount. The telescope can easily be moved to any position in the sky, there are no dead spots at the celestial pole or the zenith where it is difficult to track, and the eyepiece can be rotated to any position. This might be one of the easiest to use telescope mounts, but every commercial telescope ever built which uses this kind of mount has had some caveats.

The trouble with beginner telescope mounts is this: A good telescope mount (one which will keep it stable, in balance, and won’t wear out) costs about as much as the telescope it is designed to carry. This is true except for pretty much any mount design, except for one, Dobsonians. The result is that to keep costs down, telescope manufacturers focus on the optics of the telescopes while cutting corners on the mounts and accessories. (Though sometimes they just cut corners everywhere, including the optics, which is how you get utter trash like the PowerSeeker series)

Altitude-Azimuth Mounts

Probably the majority of cheap beginner telescopes come on some variety of altitude-azimuth mount. Let’s look at some of the types and their pros and cons.

  • Dobsonian: Cheap, effective. See below. Absolutely recommended for a newtonian.
  • Photo Tripod Style: This is one of the most common types. The mount is essentially a photo tripod adapted to carry a telescope. It may be a little heavier and sturdier than a standard photo tripod and may be fitted to accept a vixen dovetail (As in the AstroMaster AZ telescopes), or it may be a cheap finicky thing which is screwed onto the telescope. The photo tripod style is marked by a handle coming out the back which is used to point the mount. Some small telescopes and binoculars have fittings for a photo tripod, so a standard photo tripod can be used. This mount is inherently impossible to balance, but a good photo tripod will have knobs which can be tightened enough to prevent the telescope drifting when pointed high in the sky.
  • Simple Hinge: Here, the altitude axis is a simple hinge which goes back and forth and may have a tension knob. These are awful, avoid them. They have the same balance issues as the photo tripod except worse, and they’re often built incredibly poorly. Not recommended. Note: some hinge or photo-tripod style mounts might include a large counterweight to keep the telescope in balance. Though I can’t speak to the stability of those systems, they can at least be balanced to prevent drifting.
  • Simple Fork/Yoke: Mechanically very simple. The telescope is screwed between the prongs of a fork, which is mounted on an azimuth bearing in the tripod. The fork is usually offset backwards so that the telescope can be pointed straight up without running into the tripod. Sometimes you’ll see a straight metal rod connecting the fork to the telescope, which functions as a slow-motion dial. If the fork is sturdy and metal, it can be worth using, and is probably the best altaz mount for a beginner lens-based refractor telescope. If it’s thin, flimsy plastic, you’re out of luck.
  • Go-To Fork: Here, the fork and the base are much sturdier, and contain motors to move the telescope in altitude and azimuth. Often you’ll find undermounted beginner telescopes, where the mount is a capable device, but it’s carrying a telescope too heavy to reliably move and track without issue. Half-forks are a more common variant of this in beginner telescopes, where the telescope is supported by a single altitude arm rather than two. These are mostly used with Cassegrain telescopes, but they can be found with Newts and Refractors as well. As long as the mount isn’t too undersized, they are fairly decent. However, I’ll describe later why I don’t recommend computerized telescopes for beginners.
  • There are other unique designs, and sometimes you’ll find variants of each of these with slow motion knobs and cables, but these are the most common in beginner telescopes.

The One True Beginner Telescope Mount – Dobsonians

Orion Skyquest XT6By far the best mounting option for a beginner reflector telescope is a Dobsonian or a Tabletop Dobsonian. These mounts are almost always paired with Newtonian reflector telescopes (particularly good bang for your buck as they can be made cheaply with large apertures), but you’ll occasionally see Maksutov Cassegrains (or even, in amateur telescope making circles, Refractors) with a Dobsonian type mount. A Dob is a mechanically simple, elegant Altitude-Azimuth design. A lazy-susan mount provides the “all-around” motion, and a rocker box and simple friction-fit bearing provide the “up, down” motion. The bearings are simply Teflon strips, and the construction is made of wood or particle-board. They are exceedingly cheap to manufacture compared to any other mount which is worth using, and yet they are incredibly effective. A Dob allows you to simply grab the telescope and push it to where you want it, and it’ll stay there. Even at very high magnifications (200x, 300x), shaking and wobbling are manageable and the motions are smooth enough to track with.

Full-size Dobsonians of 6” aperture sell for the same price as some of the Equatorial Mounted Tripodal offerings from big brands like Celestron, and will be easier to use with a better optical performance. They have, by far, the best bang for your buck of any kind of telescope.

Equatorial Mounts

Celestron Powerseeker 127EQThere are basically two kinds of equatorial mounts: Go-To Forks and Half-Forks which are placed on an equatorial wedge (uncommon in entry-level telescopes), and German Equatorial Mounts.

Even if you get an EQ-mounted telescope which is actually within the mount’s payload range, it will still be frustrating to learn to use properly unless you’re fairly experienced. For most of the time I owned my AstroMaster 114EQ, I never used the mount properly because I didn’t understand how. Only after I had a formal education in amateur astronomy, did I understand how to use the equatorial mount properly, but by then it was so worn out that I ended up getting rid of it.

For the same price as a telescope on a really good equatorial mount, you can get a much larger Dobsonian telescope, and you’ll have more fun with it. The only time when an equatorial mount is really important for the beginner astronomer is if they must have the ability to track and take astrophotos.

Roll With It: The Infinite Axis Ball Mount

A Ball-mounted telescope, such as the Edmund AstroScan, has been out of fashion for the past decade or two, which is kind of a shame. They’re even easier to use than the Dobsonian mount, and they’re a little more versatile. However, there are a few drawbacks worth discussing.

  • Unlike most other mounts, it’s impossible to adjust the tension or friction on the ball mount. If you find it moves too easily, or if it becomes slightly unbalanced, it isn’t possible to clamp something down and prevent it from rolling out of place. In practice, I found this is mostly only a problem when you’re pointing at the horizon.
  • Most ball mounts do not allow for collimation (alignment) of the primary mirror. So if it gets bumped out of place, or ships with it out of place, there’s not much you can do to fix it. I have seen one example of a small ball-mounted telescope that has primary collimation, but it isn’t common.
  • The ball gets in the way of sighting along the tube or looking through any kind of finderscope placed normally on the front of the tube. However, this has been worked around by simply lengthening the strut attaching the finder to the telescope tube.
  • It is practically impossible to use with optical designs other than the Newtonian reflector.

Still though, for how easy to use they are, I can’t speak too poorly about them, conceptually. The only problem is you’re not likely to find any new ball-mounted scopes anymore, as after the AstroScan stopped being made around the turn of the millennium, its knock-offs followed suit. A tabletop Dobsonian is a fine substitute, however.

The Importance of a Tripod, and Why to Avoid Them.

Because of the cut corners in most beginner telescope mounts and the clear superiority of the Dobsonian, I do not recommend any beginner telescope on a tripod, by default.

Beginner telescopes are sold with some pretty awful tripods. Sometimes, the mount is decent enough, but the tripod it is attached to is dreadful. Springy, loose, wobbly. It can be hard to tell for sure just by looking, but in my experience tripods with thick round legs are best. The thin aluminum rectangular legs on many modern beginner telescopes are poor performers because they’re not stiff enough–they’ll twist if you’re trying to move the telescope in azimuth. Wooden tripods are not found in new telescopes anymore, but they may be sturdier than the flimsy aluminum ones. A few tricks to increase the stability of a tripod:

  • Tie a heavy counterweight, something like the weight of a gallon or half of water, to the underside of the top of the mount.
  • Spread the tripod legs out as much as possible to keep them slightly under tension.
  • Don’t extend the tripod legs, keep them at their lowest length.

Dobsonians and tabletop telescopes do not rely on tripods. They use three small feet to maintain a three-point contact on a surface, but these are not really structural. A Tabletop telescope requires a sturdy table, stool, or chair to mount on. However, they can also use parts of the environment–rocks, walls, the hood of the car you brought it out to the dark site with, etc. A full-size Dobsonian rests on the ground. Because their wood deforms if it gets too wet, it may be best to lay down a large plastic bag or a tarp to keep it dry in dewy grass. But the telescope is usually long enough that you can easily use it by sitting down in a chair at the eyepiece, without a tripod needed to bring it to eye level.

Dovetails

A very nice feature for a telescope to have is a Vixen Dovetail, which is a generic mounting standard to allow any telescope to be mounted on any compatible mount, regardless of manufacturer. Dovetails allow for your mount to accept a different telescope, or your telescope to be placed on a different mount, providing a potential upgrade path for your existing equipment. It is not entirely necessary though, and many beginner telescopes do not include this option or they simply can’t due to the geometry of their mounts.

Unmounted or Handheld Telescopes

I would regret it if I didn’t at least mention handheld telescopes. In addition to binoculars, some exceedingly cheap telescopes come with no mount at all. This is a huge red flag that what you’ve bought is simply a toy with poor optics. There are exceptions: Handheld monoculars are essentially half of a pair of binoculars, and they can be found for very attractive prices (half that of an equivalent pair of binoculars, as you might imagine). And then there is the Galileoscope, a telescope kit originally sold at a loss for around 20 dollars (Though it now goes for a much less attractive 70 dollars). To keep the costs very low, they do not provide a mount, only a ¼ 20 mounting washer for photo tripods.

A handheld telescope is limited severely in maximum magnification. Beyond about 15x, a handheld instrument becomes too shaky to use. I often find my lightweight 12×50 monocular difficult to use handheld when looking for sharp objects like Jupiter’s Moons and craters on our Moon, and using the Galileoscope handheld is nearly impossible.

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