What We Like About Sky-Watcher Dobsonians

Sometimes simple is best. A Skywatcher Dob will introduce you to deep-sky astronomy at a price that is usually reserved for smaller (and therefore less powerful) telescopes.

With a Skywatcher Dobsonian, you’ll become more than an observer of the cosmos; you will actively participate in finding objects and feel the excitement of discovery.

Classic Sky-Watcher Dobsonians come with a Tension Control Handle; a real improvement that allows you to lock the tube in its current position, adjust the tension between the tube and mount to accommodate a heavier eyepiece or Telrad finder, etc. You can read more about this patented Dobsonian improvement below.

Many smaller Dobs come with a 1.25” focuser, but the Sky-Watcher includes a 2” focuser with an 1.25” eyepiece adapter, allowing you to use both 1.25” and 2” eyepieces and barreled accessories, like Barlow lenses and collimators.

Also included with the 6” SW Dob is two (2) 1.25” eyepieces (10 mm & 25 mm), and a 6 x 30 finder.

What is Dobsonian Telescope?

John Dobson, an avid amateur astronomer connected to the San Francisco Sidewalk Astronomers, designed a simple yet elegant telescope mount in the 1970’s that was easy to build and could handle a basic Newtonian telescope tube. Dobson wanted people to have the ability to build their own telescope out of inexpensive materials. In fact, hundreds of people, under Dobson’s tutelage, learned to grind their own mirrors, and these mirrors were put to use in what has come to be known as a “Dobsonian” telescope.

What makes a telescope a Dobsonian is the base that the telescope tube sits on. The tube itself is a simple Newtonian, designed by someone you may have heard of…Isaac Newton. Before John Dobson invented his simple telescope base, Newtonian telescopes were usually mounted on a large, heavy equatorial mount. They were neither simple, portable, nor inexpensive. Instead, Dobson made a heavy-duty box, modified to hold the optical tube, and mounted it on a lazy-suzan type base. The telescope tube only took a few simple modifications to allow it to ride on the base. When he had finished the final tweaking, a new alt-azimuth mount was born. The telescope could be pointed to anywhere in the sky by either rotating the box on the lazy-suzan base, or by pushing the telescope up or down. The Dobsonian was born.

How the Sky-Watcher Tension Control Handle Improved the Dobsonian

The Dobsonian mount usually relies on the friction between the side bearings on the optical tube of the telescope and a frictional material on the saddle to hold the optical tube in place. If there is too much friction, the telescope is difficult to move to center an object in the field of view. If there is too little friction, the telescope will not stay where it is positioned. This makes stabilizing the optical tube of the telescope difficult when using a Dobsonian mount, especially when accessories, such as a finderscope or an eyepiece, are added to the optical tube. As long as the amount of friction is at an appropriate level, and therefore stabilization of the optical tube is achieved, the telescope can remain in its desired position to view an object and maintain its position, even when the mount is rotated.

The currently available devices for stabilizing a telescope on a Dobsonian mount include a sliding weight to counter balance the weight of the telescope, a friction lock that must be adjusted to inhibit movement of the telescope, and a spring attached between the telescope tube and mount to aid in stabilization. These devices are inconvenient to use because they do not provide a simple and user-friendly way to adjust the friction.

The object of the Sky-Watcher Tension Control Handle invention (US Patent No. 6,940,642) is to provide a tension adjuster that users can easily turn to add or reduce tension, thereby increasing or decreasing the friction between the optical tube and the sideboard of the mount. By providing such a tension adjuster, the telescope does not need to be balanced in order to stay in position. The tension adjuster can be tightened such that the optical tube can stay in a position but can still be moved when prompted to adjust the position of the optical tube. Alternatively, the tension adjuster can be completely tightened to lock the optical tube in position.

Sky-Watcher Classic 6” Dobsonian Telescope