Orion 10" Truss Tube f/8 Ritchey Chretien Reflecting OTA Telescope

Unlike Newtonian reflector and Schmidt-Cassegrain designs that are susceptible to coma away from the center of the field, the Orion 10" f/8 Truss Tube Ritchey-Chrétien Astrograph utilizes hyperbolic primary & secondary mirrors to achieve wonderfully flat images that are virtually coma-free. Since there are no lenses involved, images are also free of chromatic aberration, showing off true color. Both the 10" (250mm) primary mirror and the secondary mirror are made of low-expansion quartz glass. With enhanced aluminum coatings, the mirrors provide 96% reflectivity. The primary mirror is fixed in place to eliminate image shift that plagues Schmidt- and Maksutov-Cassegrain designs. The secondary mirror is precisely center-marked for easly collimation.The carbon fiber truss system is thermally stable, minimizing the effect of ambient temperature changes on the telescope's focus. Plus, since it's an open tube, the optics cool down faster than solid tube versions. The Serrurier system uti