CELESTRON EDGE HD 925
Celestron
Aplanatic Schmidt-Cassegrain
9.53 kg
CELESTRON EDGE HD 925 is backordered and will ship as soon as it is back in stock.
The Celestron Edge HD 925 is an aplanatic flat field Schmidt-Cassegrain which provides aberration-free images across a wide field of view. A true astrograph, the EdgeHD 925 provides a 42mm image circle, making it suitable for full frame sensors.
Celestron's EdgeHD series combines the strengths of Schmidt-Cassegrains with imaging performance of modern Corrected Dall-Kirkham designs, all in an affordable package. The classic SCT is well corrected on-axis but suffers from coma and field curvature, making them unsuitable for deep sky imaging. By adding a two-element corrector lens and optimizing the overall optical design, the EdgeHD solves these problems while keeping costs low for a full frame-corrected instrument. The EdgeHD series includes Celestron's StarBright XLT optical coatings on each surface, giving maximum light transmission across the visual and photographic spectrum between 400 - 750nm.
In addition to the optimized optical design, the EdgeHD includes flexible tension mirror clutches which reduce image shift over long exposures. This allows the mirror to be held securely in place without putting additional force or pressure on the mirror assembly. Filtered cooling vents on the rear cell let hot air to be expelled from behind the primary mirror.
The EdgeHD is an incredibly versatile instrument, with a 0.7x reducer available separately and Fastar/Hyperstar compatibility for super-fast imaging at f/2.
Every EdgeHD is tested in-house by Celestron to ensure its high optical performance and the surface quality of each optical surface.
Specifications
Optical design | Aplanatic Schmidt-Cassegrain |
---|---|
Aperture | 234.95 mm (9.25") |
Focal length | 2350 mm |
Focal ratio | f/10 |
Resolving power | 0.49 arc seconds |
Image circle | 42 mm |
Light gathering power | 1127 times the human eye |
Central obstruction diameter | 85 mm (36% of aperture diameter) |
Wavelength range | 400 - 750 nm |
Optical coatings | StarBright XLT |
Backfocus from rear flange | 146.05 mm |
Mount attachment | CGE dovetail plate |
Threads | 3.28"-16 |
Tube length | 559 mm |
Tube weight | 9.53 kg |
Tube diameter | 271.78 mm |
SKU | CE-91040-XLT |
Items included
- EdgeHD 925
- CGE dovetail
- 9 x 50 finderscope
- 2" mirror diagonal
- 23mm Luminos 2" wide-angle eyepiece