Celestron's EdgeHD is an aplanatic, flat field Schmidt-Cassegrain telescope that produces aberration-free images across a wide visual and photographic field of view. The optical system was designed to reduce more than just off-axis star coma; it also provides an astrograph-quality flat focal plane all the way to the edge of the field of view. 

Features Include:

• Experience our best optical performance with EdgeHD’s aplanatic, flat field Schmidt-Cassegrain optics for pinpoint stars all the way to the edge of today’s largest imaging sensors and widest eyepieces.
• Aluminum optical tube with tube vents featuring an integrated 95-micron mesh filter allows hot air to be released from behind the primary mirror. Mirror support knobs hold the mirror in place and reduce image shift during imaging.
• Versatile design accommodates 3 focal ratios: native f/10, f/7 with the addition of a focal reducer, or ultra-fast f/2 imaging with a removable secondary mirror and third-party accessories.
• Celestron’s premium StarBright XLT coatings provide maximum light transmission.
• A 9x50 finderscope, 1.25” mirror diagonal for more comfortable viewing, and 40 mm Plössl 1.25” eyepiece are all included.