Celestron CGEM II 11-Inch EdgeHD Schmidt-Cassegrain TelescopeCelestron CGEM II 11 Inch EdgeHD Telescope combines Celestron's CGEM II computerized equatorial mount with its acclaimed EdgeHD optical system. With an optical tube assembly weighing only 28 lb. This telescope is portable enough to be taken to dark skies, and has 89% more light gathering power than an 8 Inch telescope and 40% more than the 9. 25 Inch. Celestron CGEM II 11 Inch Optical Tube EdgeHD is an aplanatic, flat field Schmidt Cassegrain