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A review in Astronomy magazine said that the 10” Orion SkyQuest XT10 Dobsonian “offers a pleasing design, great optics . . . I have to say the XT10 [Classic] possesses the best mass-produced Newtonian optics I have seen.”

The Orion SkyQuest XT10 Classic’s great light-gathering capacity (over 1300 times that of the human eye) makes it ideal for capturing very faint deep space wonders from a dark sky observing site. Binary stars, open and globular star clusters, faint nebulas and galaxies – all are revealed in exceptional and subtle detail. At the same time, good planetary and lunar images are yours for the looking, although a neutral density or variable polarizing filter is invariably needed to cut down the brightness of these solar system objects.

The Orion SkyQuest XT10 is human powered. You move the scope manually – which is faster, quieter, and much less expensive than a motorized system. With only two major components to assemble (tube and base), and a heaviest single component weight of a little under 31 pounds, the scope takes only a few minutes to set up and is easily managed by any reasonably fit individual. It can be used in your back yard or at a distant dark sky site (the preferred observing location if you want to get the most out of its faint object observing capabilities). Its good optical quality and very reasonable price for such a big telescope make it an excellent buy for the beginning and advanced astronomer alike.

This Telescope’s Optical System . . .

Newtonian reflector optical tube: 10” (254mm) aperture classical Newtonian optics, 1200mm focal length, f/4.7 focal ratio. The durable 47.8” long x 12” diameter rolled steel optical tube is finished in gleaming black enamel. It weighs under 31 lbs, making it surprisingly easy to transport and assemble in the field.

Fully coated optics: The 10” parabolic primary mirror is coated with highly reflective aluminum and overcoated with a protective layer of quartz for long life.

Primary mirror cell: Die cast aluminum cell with open back design for faster cool down times. A battery-operated cooling accelerator fan that mounts on the rear cell is also available as an option. Push-pull locking collimation screw pairs help hold the correct collimation longer.

Diagonal mirror: The 2.48” m.a. diagonal is coated with aluminum and overcoated with a protective layer of quartz for long life. It is mounted in a fully-collimatable mirror holder on a thin four-vane spider for minimum diffraction and higher contrast.

Finderscope: The EZ Finder II non-magnifying illuminated red dot finder projects a small dot of red light on a clear viewing window. The dot is focused at infinity to show you precisely where your scope is pointed. Simply move the scope until the red dot on the 10° wide viewing window lines up with an object you want to see and your scope eyepiece will automatically be centered on that object. You see the sky through the EZ Finder II viewing window the way it appears on star charts, making it easy to orient yourself on the sky. There’s no confusing mirror image or upside down view such as the one you see in a conventional magnifying finder. The brightness of the red dot is adjustable to suit your preference. Thumbwheels allow fine positioning of the dot horizontally and vertically for precise alignment with the main telescope.

Focuser: 2” aluminum Crayford type, with removable 1.25” eyepiece holder. The Crayford-style focuser has smooth backlash-free motion that eliminates image shift, making it easier to achieve the sharpest possible focus.

Eyepiece: A multicoated 25mm 1.25" Sirius Plössl is standard equipment. The 25mm eyepiece provides 48x, with a 1.08° field, more than twice the diameter of the full Moon, for expansive deep space views.

Collimating tool: A pinhole-type collimating cap that fits into the focuser drawtube allows quick alignment of the primary and diagonal mirrors. If more precise alignment is desired, an optional battery-powered LaserMate laser collimator is available. The primary mirror is center-marked for easier collimation.

Software: Included is a special edition CD-ROM of Starry Night software. This is a very capable basic first step into exploring the night sky on your PC or Mac computer. You can use it to plan your observing sessions and print out star charts on your computer to take out with your telescope to explore with your own eyes the objects the program shows you.

This Telescope’s Mount . . .

Dobsonian mount: The particle board Dobsonian altazimuth mount base has a triangular ground board (rather than circular) to reduce the weight of the base to 24.6 pounds. The base has a convenient carry handle and an eyepiece rack that can hold three 1.25” eyepieces and one 2” eyepiece. The base is shipped disassembled and needs to be assembled only once, unless you decide to disassemble it to save space for long-term storage. The assembly process takes about 30 minutes and requires no special tools.

Altitude and azimuth bearings: The altitude bearings rest in ultra-high molecular weight (UHMW) polyethylene pads for smooth vertical motion. The azimuth bearing uses Teflon bearing pads for equally smooth “stiction-free” horizontal motion.

CorrecTension balance system: The dual spring tension system applies the correct level of tension to the altitude bearings to balance the weight of different eyepieces. With the CorrecTension system, you can change eyepieces or add a Barlow lens without having to hold the tube in place in altitude by hand or tediously adjust the telescope’s balance with counterweights as you do with other Dobsonians when the eyepiece weight changes. This is particularly important with this scope, given its ability to use heavy 2” eyepieces.

What can you see though the Orion SkyQuest XT10 Classic? Under dark skies, the Orion Nebula becomes a glowing complex of filaments that more than fills the 1.08° field of the scope’s standard 25mm Sirius Plössl eyepiece. The spiral structure of the Whirlpool Galaxy becomes apparent, as do dark dust lanes across the nucleus of the Andromeda Galaxy (although the full 3° width of the galaxy itself is far too large to fit into the field of view of the eyepiece). Globular star clusters are often resolved to the core. Messier, NGC, and IC objects show detail and structure never visible in smaller telescopes. As with any large aperture telescope, the performance of the 10” SkyQuest Classic on faint objects will be markedly improved by a dark sky observing site. Light-polluted city and suburban sites are not recommended as the primary observing site for a 10” scope. Such sites require a nebula (light pollution) filter to take even limited advantage of its immense light-gathering (over 1300 times greater than the sharpest dark-adapted eye).

While it is in deep space observing of galaxies and nebulas from a dark sky observing site that the 10” Orion SkyQuest XT10 Classic excels, significant planetary and lunar observing is also within its capability. All you need is a neutral density or variable polarizer eyepiece filter to cut down the immense brightness of solar system objects seen through this “light bucket.” Photography is not possible with this manually-operated Dobsonian telescope. The 10” Orion SkyQuest XT10 Classic is designed for visual observing only – to show you faint deep sky wonders by the hundreds and thousands. It does that marvelously well, and at a surprisingly affordable price.