Celestron Focal Reducer 0.7x for Edge HD 800
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Vai al moduloThe Celestron 0.7x focal reducer for Edge HD 800 (item 94242) is the official optical accessory that brings the EdgeHD 800 system from f/10 to f/7, halving exposure times and widening the field of view by 43%. Its 4-element design in lanthanum and rare-earth glass preserves the signature flat-field correction of the Edge HD system, delivering pinpoint stars from center to edge — perfect for imaging nebulae, galaxies, and clusters with cooled CMOS cameras or modified DSLRs on sensors up to APS-C format.
Optical Design Dedicated to the Edge HD 800
Unlike generic focal reducers, this accessory is optically computed specifically for the Edge HD 800 and maintains its 105 mm backfocus, keeping full compatibility with Celestron T-Adapters and all dedicated imaging accessories. The CNC-machined aluminum housing provides precise spacing, alignment, and centering of optical elements. All lens edges are blackened to eliminate internal reflections and maximize image contrast.
Technical Specifications
| Parameter | Value |
|---|---|
| Optical design | Reducer-flattener, 4 elements |
| Reduction factor | 0.7x |
| Resulting focal ratio | f/7 (from f/10) |
| Optimal backfocus | 105 mm |
| Fitting | 2" — 24-thread M/F on both sides |
| Optical coating | Broadband multilayer anti-reflection |
| Optical glass | Lanthanum and rare-earth, high-refractive-index |
| Exposure time reduction | 50% (1 full stop gain) |
| Field of view increase | 43% |
| Compatibility | Celestron Edge HD 800 exclusively |
| Item code | CSCE94242 |
Installation and Compatibility
The reducer threads directly onto the 2" rear threaded port of the Edge HD 800 tube. Its large-diameter aperture reduces mechanical vignetting and makes the system compatible with APS-C sensors and off-axis guiders (OAG). A specific photographic adapter for the EdgeHD 800 is required to complete the imaging setup (not included).
Compatibility Note
The Celestron 94242 reducer is designed exclusively for the Edge HD 800 telescope. It is not optically compatible with the standard C8 or any other Schmidt-Cassegrain or Cassegrain telescope of different aperture or optical design.
Who It’s For
Ideal for astrophotographers using the Celestron Edge HD 800 who want a faster, brighter system with a wider field of view, without losing the flat-field correction that defines the Edge HD line. Compatible with ZWO ASI, QHY, Player One cameras and modified DSLRs.