Orion Sirius 100ED EQ-G GoTo Refractor Telescope Kit, with Eyepiece, Tripod & Mount and Software.

The Orion Sirius 100ED EQ-G GoTo Refractor Telescope is for the astronomy purist who wants the pristine, high-contrast images that only a premium apochromatic refractor can deliver and the object-finding precision and convenience that only a well-made GoTo mount can offer. 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.

The 100mm aperture gives it 56% greater light grasp than theED80, 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 has the stability you need to enjoy steady images at high powers. With the GoTo controller, you will never run out of fascinating targets to view. And once you get a taste of automatic, computerized pointing, you will never go back to manually "searching" for objects again.

The mount's internal dual-axis stepper motors slew your telescope at up to 3.4° per second right to your target. Other features include a CCD autoguider port for imaging, periodic error correction (PEC), backlash compensation for GoTo slewing, latitude and azimuth adjustments for polar aligning and an illuminated polar axis scope. The tripod is remarkably sturdy, featuring extendable 1.75"-diameter stainless steel legs and a cast-metal spreader plate. It requires 12V DC power source such as the Orion Dynamo or AC-to-DC adapter for use of household 110V power.