The Celestron EdgeHD 9.25" SC tube 9.25-inch (235 mm) Schmidt-Cassegrain telescope is based on the earlier C9.25 series, but thanks to the built-in two-element corrector, it is free of the coma defects and curved image planes typical of the model, so it images stars point-like right to the edge of the field of view. The compact size of the Celestron EdgeHD 9.25" SC is a true all-rounder, hiding behind its compact size is a very serious performance and excellent optics. The telescope is ideal for both visual and photographic purposes.
As with the Celestron EdgeHD 9.25" SC, as with the C9.25, the auxiliary mirror can be removed and a CCD camera can be fitted directly in place with the appropriate adapter, in which case the telescope is equipped with an extra bright F2 system. Of course, the common SC accessories can also be easily fitted to the tube. Filtered vents on the telescope tube help to allow faster heat dissipation. The annoying feature of catadioptric binoculars, the "image shift" mirror tilting when changing direction, has been minimised in EdgeHD binoculars by a more mechanically stable focusing system. Special mention should also be made of the practical, sturdy handle on the tube.
The standard accessory is the company's proprietary StarBright XLT coating, which increases the light-harvesting capability of the binoculars. When used, the transmission of the corrective lens reaches 98%, while the reflectivity of the main and auxiliary mirrors reaches 95%. In addition, the contrast of the image is increased. The basic package also includes a zenith mirror, a 9x50 finder scope and a 40 mm Plössl eyepiece.
Celestron tubes are hand-figured and hand-matched, which means that they consistently outperform the optical quality of competing SC tubes in various tests.
