Orion® Sirius™ 100ED EQ-G GoTo Apochromatic Refractor
Apochromatic refractor telescopes use lenses to bend different wavelengths of light at different angles which means the stars you see will usually have a blue/violet ring around them as this light is bent more than the rest of the spectrum. With a price tag just below $2,000, this telescope is certainly not one for for the budget-conscious but with this device boasting a 'premium apochromatic refractor' you would be hard press to access similar quality images from any ordinary scope.
Description:
The ED100 delivers images remarkably free of chromatic aberration, thanks to the FPL-53 extra-low dispersion “ED” optical glass in one of the two objective lens elements. That, combined with the 900mm focal length (f/9.0), ensures that bright stars, planets, and the lunar limb won’t be marred by color fringing as with standard achromats. What’s more, the 100mm aperture gives it 56% greater light grasp than our ED80, letting you push the magnification higher to resolve finer details. The baffled, 36"-long aluminum tube is outfitted with a 2" Crayford-style focuser (with 1.25" adapter) for exceptionally smooth focusing without backlash.
The Sirius EQ-G mount has the stability needed to enjoy steady images at high powers. And with its precision GoTo pointing to 13,400+ celestial objects, you will never run out of fascinating targets to view from the complete Messier, NGC, and IC catalogs. Internal dual-axis stepper motors slew your telescope at up to 3.4° per second. Altogether there are ten slew rates, from 1.5x to 800x, plus three tracking rates.
Other features include a CCD autoguider port for imaging, periodic error correction (PEC), backlash compensation for GoTo slewing, large R.A. and Dec. locking levers, latitude and azimuth adjustments for polar aligning, an illuminated polar axis scope, and an 8.3" dovetail mounting bar. The tripod is remarkably sturdy, featuring extendable 1.5"-diameter stainless steel legs and a cast-metal spreader plate/accessory tray.
Requires 12-volt DC power source such as the Orion Dynamo or AC-to-DC adapter for use of household 110-volt power. One-year limited warranty.
Source:Orion Telescopes & Binoculars