The Orion 8 inch Ritchey-Chretien Astrograph's outstanding optical design lets you capture spectacular, detailed images of deep-sky objects like never before. Unlike conventional Newtonian reflector and Schmidt-Cass grain designs that are susceptible to coma away from the center of the field, the Ritchey-Chretien utilizes hyperbolic primary and secondary mirrors, made of BK-7 optical glass, to achieve wonderfully flat-field images that are virtually coma-free. Images are also free from chromatic aberration, since there are no lenses. The Orion 8 inch Ritchey-Chretien Astrograph is ideal for use with small CCD-chip cameras such as the Orion Star Shoot line, as well as medium-format CCD and DSLR cameras. The telescope's wide, fully illuminated flat field produces pinpoint star clarity all the way to the edge of the camera's sensor. The Orion 8 inch Ritchey-Chretien Astrograph features a machined, dual-speed (10:1) Crawford-style focuser with an engraved millimeter scale on the drawtube. The secondary mirror is precisely center-marked to facilitate collimation. The enameled steel optical tube weighs only 18.5lbs. and features a Losmandy-style dovetail mounting bar underneath for trouble-free setup on medium or large-sized equatorial mounts. The inside of the optical tube is fortified with eight computer-positioned light baffles, and the primary mirror baffle tube and secondary mirror light shield are also highly baffled to ensure maximum image contrast.
