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(Sky-Watcher 90mm Refractor Telescope
This deluxe refractor telescope provides ultra-sharp high-contrast images of the Moon and planets, good views of the brighter deep space objects, and even delivers satisfactory performance with city light glow. All of this is combined with a solid, simple-to-use mount and the setup is highly portable.Save $105 on this Skywatcher telescope for limited time!
Refractor telescopes have greater light transmission than reflectors which means better image quality per aperture diameter. This 90mm (3.5”) refractor combines the great image quality of a refractor with the increased light- and detail-gathering ability of larger reflector telescopes. If you enjoy observing the moons of Saturn and the bands of Jupiter, or studying the surface of the Moon in detail, then this is the scope for you. Plus it provides clarity and detail for deep space objects and delivers an upright image for terrestrial viewing.
You'll appreciate the optical quality of this scope. The 90mm achromatic doublet objective lens is precision polished and multi-coated for optimal performance. Plus you get two premium Plossl 1.25” eyepieces: one 25mm and one 12mm. These multi-coated 4-element eyepieces are the same as those supplied on much more expensive telescopes and they have a wide 52° field-of-view and great eye relief (important if you wear glasses).
The mount is a unique AZ3 altazimuth design. It provides a rock-solid base for this telescope while making it easy to locate and track objects. The slow-motion controls allow fine movement in both the vertical and horizontal direction—just turn the cable control knobs. This mount is much easier to use than the more complex equatorial design.
Other quality features include a red-dot finderscope for easy object locating, deluxe 1.25” 45° prism diagonal for viewing comfort, 2x Barlow lens to double magnification of each eyepiece, and Planetarium software for your PC. For help finding the telescope that's right for you, see our Selecting a Telescope guide.
Note: Standard Shipping and shipping specials are not available for this bulky item. This item only ships to a street address in the 50 US states with UPS Ground shipping.
Product Specifications
- 90mm diameter multi-coated objective lens made from grade-A crown and flint glass
- 900mm focal length, f/10.0
- 9.8 sq. in. light grasp
- 213x maximum theoretical magnification and 1.56 arc-sec resolving power
- High-quality super Plossl fully-coated 25mm and 12mm 1.25” eyepieces provide clear, sharp images at magnification of 36x and 78x with a 52° apparent field-of-view and great eye relief
- 1.25” 2x Barlow lens doubles magnification of the included eyepieces to 72x and 156x for up-close planetary and lunar viewing
- Precision 1.25" rack-and-pinion focuser
- Deluxe 45° prism diagonal for viewing comfort
- Red-dot finderscope with variable brightness makes locating night-sky objects easy
- Unique AZ-3 altazimuth mount provides solid stability with dual slow-motion controls in both the vertical and horizontal directions
- Deluxe aluminum tripod with accessories tray
- Aluminum optical tube with enamel finish
- Includes easy-to-understand instructions for use and assembly
- Includes TheSkyX Student astronomy software for PC computers (XP or Vista with DVD required). TheSkyX Student is a comprehensive and full-featured tool to help you explore and actively develop an understanding of basic astronomy. You can learn the constellations (labeled with their phonetic pronunciation), watch planetary motion over days or centuries, witness solar and lunar eclipses, and much more ($79 value.)
- Weighs 9 lbs with a 36" tube length
- One year warranty from Sky-Watcher USA, Sky-Watcher model GreatStart 90AR-AZ3 telescope
Telescope Magnification:
Don't make the mistake of buying a telescope for the high magnification advertised. Many low-priced telescopes boast magnification of over 300x, which is totally unusable for three reasons.
- First, the theoretical magnification for any telescope is limited by aperture (primary lens or mirror) diameter. The maximum theoretical magnification is 120x for a 60mm telescope and 228x for a 114mm telescope.
- Second, atmospheric conditions limit magnification to 200-250x on the very best of nights even with very large telescopes.
- Third, the low quality optics on most inexpensive telescopes do not produce a clear, sharp image even at lower magnifications.
Most night sky observing is done in the range of 25x-150x. The Sky-Watcher telescopes we offer have excellent optics at these magnification levels, ensuring you will enjoy your night sky viewing.
