Sky-Watcher Traditional Dobsonian Telescope (AVAILABLE FOR IN-STORE PURCHASE ONLY)

John Dobson, an avid amateur astronomer connected to the San Francisco Sidewalk Astronomers, designed a simple yet elegant telescope mount in the 1970s that was easy to build and could handle a basic Newtonian telescope tube. Dobson wanted people to have the ability to build their own telescopes 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 a 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 it 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 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.

The currently available devices for stabilizing a telescope on a Dobsonian mount include a sliding weight to counterbalance 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 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.

The Sky-Watcher 10” Dobsonian features a primary mirror made of Pyrex glass. Because of its very low coefficient of thermal expansion, Pyrex glass is less affected by changing temperatures. This greatly reduces the cooling time of a telescope larger than 8” in diameter without using an extra fan. The great stability of this low-expansion glass ensures high-quality images. It is also substantially more resistant to scratching than plate glass.

• Optical Design: Newtonian
• Mirror Type: Parabolic
• Primary Mirror Aperture: 254 mm
• Secondary Mirror Aperture: 58 mm
• Focal Length: 1200 mm
• F/Ratio: F/4.7
• Highest Practical Power: 508x
• Faintest Stellar Magnitude: 14.7
• Finder Scope: 8x50
• Focuser Diameter: 2” with 1.25” adapter
• Eyepiece: 1.25" Super 25 mm and 10 mm
• Tube Weight w/Accessories:
• Shipping Weight: 31 kg total (two boxes)

Please note that this Dobsonian will need some assembly, especially the base, which is flat-packed.

6" & 8" Dobsonians are also available in-store.

Due to the current extremely high demand & very limited supply, all telescopes are available for in-store purchase ONLY.