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Additional Info
The Stellarvue 90T is our lowest priced 90 mm apo triplet telescope. The SV90T features a 90mm f-7 (630 mm focal length) objective lens with an Ohara FPL53 center element.
Fully multicoated apo triplet objective: The high Strehl, apochromatic triplet objective provides extremely high contrast views, and several extreme broadband coatings are used on all six lens. This boosts contrast: the stars appear vivid and the background, velvet black. These coatings transmit light above and below the visual spectrum, which is important to minimize reflections seen on ccd images.
White aluminum tube and dew shield: The aluminum tube and dew shield are machined and painted white. The fittings are black anodized aluminum. The dew shield retracts reducing the length of the telescope when being stored; it extends to minimize dewing of the objective at night and serves as a glare shade during the daytime.
Internal tube treatment: The inside of the tube assembly is painted "ultra flat black" and is fully baffled to eliminate reflection. The focuser has 11 baffle ridges to reduce drawtube reflections. These ridges are painted, reducing the most commonly found type of reflected glare. This treatment provides better glare reduction than focusers that only have the ridging to prevent glare. All of these methods add up to provide the outstanding contrast of the Apo triplet lens.
Dual speed Crayford focuser with precision bearings: The 2" Crayford focuser uses a compression ring and three thumb screws to secure accessories and cameras firmly in place. A compression ring 1.25" adapter with 2" filter thread is also provided. The focuser has three focusing knobs, one on the left and two on the right. The single knob on the left and a larger knob on the right provide coarse focusing. On the right side is a second, slightly smaller, brass colored fine focus knob. This fine focus knob has an 11-1 rotation reducer, allowing for extremely fine focusing. The reducer in the Stellarvue focuser uses a hardened stainless shaft and precision ball bearings. It has greater longevity than some competitive dual speed focusers. A tension adjustment set screw is positioned under the focuser and a thumb screw allows for locking the focuser when engaged in astro-photography. The draw tube is inscribed with a millimeter scale on top. Two 5 mm threaded holes on top of the focuser allow for the attachment of two separate finder scopes. One may also mount finder scopes and accessories to the clamshell mounting ring. The focuser is fully rotating. To rotate the focuser, simply loosen the rotation knob.
Machined aluminum clamshell mounting ring with Vixen Dovetail: The SV90T uses our unique, American made, precision CNC (computer numeric controlled) machined aluminum mounting ring. This clamshell ring has several 10/32 threaded holes for mounting finderscopes, etc.
threaded holes on the side and top to accommodate a finder scope, a guide scope or another accessory. Our clamshell is precision machined and has an "easy-one-touch," single knurled knob for tightening and loosening the ring. This allows fast and convenient balancing of the telescope tube. The underside of the mounting ring has a Vixen style dovetail rail with safety grooves. This rail fits most telescope mounts on the market such as the Vixen, Celestron CG5 or Meade LXD-55. If you plan to mount this telescope on a larger mount that uses the Losmandy rail our TP6 (Losmandy sized) plate attaches to the bottom of the Vixen rail with two screws.
Supplied accessories: The SV90TBV comes with our C7 side reinforced, foam lined, airline carry on case. This case will hold the telescope, star diagonal, reflex finder and several eyepieces. In addition to the supplied accessories, you will need a star diagonal or erecting prism, eyepiece(s) and a mount. You may also want to purchase a reflex or optical finder scope.
Light gathering and magnification power: The purpose of a telescope is to gather light and magnify the apparent size of the object being viewed. A 90 mm refractor gathers 165 times the amount of light the naked- eye can. This will reveal faint objects in space. Magnification power (the increase in relative size of the object being viewed) is dependent upon the eyepiece being used. Different eyepieces provide different magnification powers. Since this telescope uses a highly accurate, hand figured objective lens and has been tested three times in the USA, it is free of coma and astigmatism seen in many import telescopes. This provides sharper details when viewing at higher powers. Dawes limit states that the maximum power for a 90 mm telescope under good conditions is about 213 powers. Check the Recommended Accessories section to make the best choice for eyepieces.
Two year warranty and Stellarvue Service: Stellarvue telescopes and accessories are covered by a two year warranty. But it does not stop there. Since we are a telescope maker, we can repair your telescope for a nominal fee years after it goes out of warranty, should you accidentally drop it on concrete or otherwise damage it. Buy a Stellarvue Telescope with confidence. Our customer care is legendary.
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