Dobsonians
What Can You See with dobsonian Telescopes?
Most Dobsonian telescopes are good for looking at deep-sky objects, including galaxies, nebulae and dim star clusters, but they also work great for enjoying the Moon and planets! The aperture (diameter of the primary mirror) of the telescope is the main factor that dictates how much detail you can see, especially when looking at celestial objects out of our Solar System. As a general rule, we recommend an 8 inch Dobsonian Telescope or larger to enjoy a wide range of deep-sky objects.
Near Space Objects – The Moon, Planets, The Sun
Thanks to the ease of the Alt-Azimuth mount and the wide field of view (FOV) generally provided by these models, they’re a perfect fit for amateur astronomers on a night of visual observing. We can twist and turn the scope to the Moon, to Mars, and the stars.
Deep Space Objects (DSOs) – Galaxies, Nebulae, Clusters
Dobs are equipped for viewing these further and fainter objects as well, although tracking these can be quite a challenge without a properly integrated system. In general, finding any object in the night sky shouldn’t take much effort at all for one of these.
Different Styles of Dobsonian Telescopes
Truss Tube Dobsonian Telescope
A truss tube Dobsonian increases portability for big Dobs by using truss poles in the center portion of the telescope tube assembly. A lot of weight is removed by using a truss tube design when compared to the closed optical tube of a traditional Dobsonian. The cool thing about truss tubes is how they can turn a big, heavy telescope into an instrument that most adults can handle. To set up or break down a Truss Tube Dobsonian Telescope, simply lift off the top section that includes the focuser and secondary and remove each truss pole. Once you have separated the optical tube into two main components (not counting the truss tubes) the amount of weight you have to carry will decrease and each section will be more portable for storage and transport. If you are concerned about the weight or bulkiness of a big Dob, the truss tube design is a game-changer!
A good example of this Dobsonian telescope design is the Explore Scientific Truss Tube Dobsonian Telescope in a 10” aperture. Explore Scientific and Orion both offer several aperture choices for truss tube telescopes.
Collapsible Dobsonian Telescope
A collapsible Dobsonian is very similar to a truss tube Dobsonian; in fact, it is common to confuse the two. Here is the difference: To break down a truss tube Dobsonian, the user removes the truss poles completely. However, with a collapsible Dobsonian telescope, the truss poles do not come out, but rather slide into the bottom part of the telescope tube assembly! It is a very neat trick that shortens the telescope considerably for travel, transport and storage, making a larger aperture Dob a more portable telescope.
A good example of this telescope design is the Sky-Watcher 12 Collapsible Dobsonian. Sky-Watcher makes a selection of their Flextube collapsible Dobs, and in fact, most of them are computerized with their SynScan GoTo system.
Classic Dobsonian Telescope
The classic, or solid tube Dobsonian has been around for about half a century and is the most popular Dobsonian style on the market. The classic is the best Dobsonian design for keeping dew off of the primary mirror, and because this telescope sports a long solid tube, it also keeps contrast-reducing stray light from hitting the primary. Setting up and breaking down a Classic Dob is easier and faster as well!
A great example of a classic Dobsonian is the Apertura AD8, our most popular 8 inch Dob, but there are lots of solid tube Dobsonians to choose from in sizes from tabletop to a 12” deep-sky light bucket!
Tabletop Dobsonian Telescope
If you want an economical, highly portable telescope that has decent aperture, a tabletop Dobsonian should be high on your list of possibilities. Because Dobsonians are designed with a short rocker box base instead of a tripod, a smaller, portable Dobsonian telescope is way easier to look through when sitting on a table or other raised, flat surface. Once Dobsonians get to about 6” in aperture they are tall enough to use comfortably for most people when sitting on the ground.
Imagine using a portable Dobsonian telescope like the Sky-Watcher Heritage 130 on a camping trip! It has enough aperture (5 inches) to see brighter galaxies and other deep-sky objects as well as the Moon, Saturn, Jupiter and Mars, and the tube collapses down to shorten it by half. Just set this portable Dob on a picnic table, insert an eyepiece, and gaze at the wonders of the Universe!
GoTo Dobsonian Telescope
If you like the idea of a big aperture Dobsonian Telescope but also want help locating celestial objects, a computerized GoTo Dobsonian is for you! Dobsonian telescopes were originally designed to be completely manual, but over the years many telescope users, especially those who enjoyed the challenge of building their own Dob, added motors, push-to systems, tracking platforms, and more to make finding objects and keeping them centered in the eyepiece much easier. Today, amateur astronomers can buy a fully decked out Dobsonian that is capable of finding and centering thousands of objects.
If you are wondering whether you can do astrophotography with a GoTo Dobsonian, the answer is yes and no. While Dobsonian telescopes are not designed for astrophotography due to their simplistic alt-azimuth mount, a determined user could take photos of the moon, bright planets and a handful of bright deep-sky objects with a GoTo Dobsonian. The set up wouldn’t be optimum, but it could be done. However, in order to do exposures longer than a few minutes, any telescope mount needs to be aligned with the celestial pole. Unfortunately, an alt-azimuth mount, regardless of the computerization, cannot be polar aligned. High Point does not recommend any type of Dobsonian or Alt-Az telescope for deep-sky astrophotography due to the above limitations. If you need help choosing a telescope for astro-imaging, a non-commissioned product advisor would be happy to help!
A popular example of a GoTo Dobsonian is the Sky-Watcher SynScan 8. This Sky-Watcher computerized 8 inch Dob is collapsible for portability and will help you explore hundreds of celestial objects with the tried and true SynScan AZ GoTo System.
