Celestron EdgeHD 8"" - General Features * 8"" EdgeHD Optical Tube Assembly * Aluminum Optical Tube * Celestron"s premium StarBright XLT coatings * 2032 mm focal length (f/10) * 40 mm eyepiece included (51x) * Visual back allows for use with 1.25"" accessories * 9x50 finderscope to help accurately find objects * Star diagonal provides more comfortable viewing position when observing objects that are high in the sky * Mirror Support Knobs hold the mirror in place and reduces image shift during imaging. * Tube vents with integrated 60 micron mesh filter allowing hot air to be released from behind the primary mirror. * Fastar Compatible optical tubes are equipped with a removable secondary mirror for fast f/2 ccd imaging * Includes dovetail rail compatible with CGE mount Specifications * Optical Design : Apanatic Schmidt * Aperture : 203.2 mm (8 in) * Focal Length : 2032 mm (80 in) * Focal Ratio : f/10 * Finderscope : 9x50 * Optical Tube : Aluminum * Eyepiece 1 : 40 mm (1.57 in) * Magnification 1 : 51 x * Star Diagonal : 1.25 * Optical Coatings : StarBright XLT * Secondary Mirror Obstruction : 2.7 in (68.58 mm) * Secondary Mirror Obstruction by Area : 11.4 % * Secondary Mirror Obstruction by Diameter : 33.8 % * Optical Tube Length : 17 in (431.8 mm) * Optical Tube Weight : 14 lb (6.35 kg) * Dovetail Compatibility : CGE Mount * Aluminum Optical Tube * Celestron"s premium StarBright XLT coatings * 2032 mm focal length (f/10) * 40 mm eyepiece included (51x)