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The optical performance of the SkyQuest XT4.5 is far and away better than that of a flimsy 60mm department store refractor (the classic beginner’s scope). Its 4.5” (114mm) mirror, housed in an enameled steel tube, gathers 260% more starlight than a 60mm refractor. More light means you can see a lot more celestial objects – and see them in greater detail. Just think of it: in any given evening with clear skies you could survey the Moon’s myriad craters in detail; then study Jupiter’s cloud bands; then star-hop among the Milky Way’s diverse star clusters and nebulas. The XT4.5 is one very revealing telescope!

The Orion XT4.5 is a true “Dobsonian” scope, having all the great features that make Dobs so popular – such as intuitive up-down/right-left maneuverability (without lock knobs or other adjustments to mess with) and sturdy no-frills support of the quality optics. The XT4.5’s base features Teflon/Nylon bearing pads, so the scope glides smoothly from object to object with just a gentle fingertip nudge of the tube. The base provides far greater stability than the tripods included with most beginner scopes, so the views are always steady. And, like Orion’s other critically-acclaimed SkyQuest Dobsonians, the XT4.5 uses Orion’s exclusive CorrecTension Friction Optimization for superior tube balance and motion control.

With the Orion SkyQuest XT4.5, stargazing is easy and fun. Its compact size, innovative design, and point-and-view simplicity make it the most user-friendly telescope for kids to come along in years. Kids ages 8 to 88, that is, because adults will appreciate its portability and excellent optical performance, too! A Sky & Telescope magazine review said, “For those seeking that mythical ideal first telescope, your search may be over . . . The SkyQuest [XT4.5] has set a new standard for the beginner’s telescope.” A Sky & Telescope review of beginner’s scopes proclaimed the XT4.5 “The best of the bunch – a solid combination of optics and mechanics.”

Don’t kill a budding interest in astronomy with a flimsy department store telescope. The SkyQuest XT4.5 is a real telescope, not a toy. It’s a quality astronomical instrument capable of delivering high-resolution images of astronomical objects. Which is why Mom, Dad, and the rest of the gang will enjoy using it, too. Hey, the line forms at the eyepiece!

This Telescope’s Optical System . . .

Newtonian reflector optical tube: 4.5” (114mm) aperture classical Newtonian optics, 910mm focal length, f/8 focal ratio. The durable 35” long x 5.5” diameter rolled steel optical tube weighs only 9 lbs, making it easy to transport and assemble in the field. A “navigation knob” at the front of the tube provides a convenient grip that makes it easy for you to move the scope around the sky.

Coated optics: The 4.5” parabolic primary mirror in its push-pull collimatable cell is center marked for easy collimation. It and the 1.1” m.a. diagonal are both coated with highly reflective aluminum, then overcoated with a protective layer of quartz for long life. The diagonal is mounted in a fully-collimatable mirror holder on a thin four-vane spider for minimum diffraction.

Finderscope: 6 x 26mm straight-through achromatic correct-image crosshair design. The view through the wide field finder is correctly oriented, just the way you see the skies with your unaided eye. This makes it easier to find your way around the heavens than the typical finder that has upside-down mirror images. The finder is mounted in a quick-release collimatable holder. Focuses by loosening the trim ring behind the objective lens cell, screwing the lens cell in or out to focus, and tightening the trim ring to lock in the correct focus.

Focuser: 1.25” rack and pinion type.

Two eyepieces: Two multicoated 1.25” Sirius Plössls, 25mm and 10mm, are standard equipment. The 25mm provides 36x, with a 1.44° field, nearly three times the diameter of the full Moon, for expansive deep space views. The 10mm provides 91x, with a 0.57° field, for closer views.

This Telescope’s Mount . . .

Dobsonian mount: The Dobsonian altazimuth mount base weighs only 8.5 lbs. The base has an eyepiece rack that can hold three 1.25” eyepieces. The particle board base is shipped disassembled and needs to be assembled only once, unless you disassemble it to save space for long-term storage. The assembly process takes about 30 minutes and requires, in addition to the supplied tools, a Phillips screwdriver and an adjustable crescent wrench. The total weight of the scope is only 17.5 lbs. It’s light enough to allow many people to pick up the scope with one hand and carry it in and out of the house using the attached handle, without having to disassemble it!

CorrecTension balance system: Easily installed removable coil springs on either side of the base and optical tube apply the correct level of vertical 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. The CorrecTension springs also keep the tube firmly connected to the base, so the whole lightweight 17.5 lb. scope can be picked up and carried as a single unit using the handle installed on the tube. There’s literally no setting up or dismantling needed each time the scope is used. Just carry the scope outside in a single piece. That’s a big plus, especially for kids.

What can you see though the Orion SkyQuest XT4.5? A surprising amount! Thanks to its relatively long f/8 focal ratio, its contrast on lunar and planetary details is astonishing. Since it is a reflector, it has none of the spurious color that masks faint planetary details in achromatic refractors. The rings of Saturn are routinely visible through the standard 25mm Plössl eyepiece at 36x, as are lunar mountain ranges and craters by the hundreds. At the 91x of the standard higher power 10mm Plössl eyepiece, Cassini’s Division in Saturn’s rings is often resolved, and the ring system itself is a magnificent sight.

While the 4.5” is exceptional within the solar system, observing the brighter deep space objects is not slighted. Binary stars are well resolved because of the scope’s high contrast. Globular star clusters are seen as fuzzy balls of light hanging in the emptiness of space, as are the brighter nebulas. The Trapezium in Orion is easily seen, wreathed in glowing nebulosity.

A Sky & Telescope review said, “The Orion Nebula showed lots of texture . . . Lots of star groupings showed up crisply in the Double Cluster . . . On Jupiter, we could see the Great Red Spot . . . Saturn showed four moons, the Cassini Division . . . and subtle zones on the globe.”

The standard equipment supplied with the SkyQuest XT4.5 makes it a complete working telescope for a visual astronomer – whether it’s your first scope or a step-up from a smaller 60mm scope. You can set it up and start observing almost as soon as it arrives. Photography is not possible with this manually-operated Dobsonian telescope. The 4.5” Orion SkyQuest is designed for visual observing only – to show you as much of the night skies as possible with a beginner’s scope. It does it very well indeed, at a surprisingly affordable price.