Celestron #94242 REDUCER LENS 0.7X - EDGEHD 800

  1. The EdgeHD .7x Focal Reducer Lens makes your EdgeHD 800 one full f-stop faster than f/10, doubling the equivalent exposure at f/10
  2. 4-element lens design
  3. Maintains similar flat-field performance as native EdgeHD optical design
  4. Increases field of view by 43% (double by area) to better capture wide field images
  5. Optimized for APS-C sized sensors, including most DSLR cameras and Nightscape CCD cameras
  6. Provides generous 105mm back focus to accomodate additional accessories and a wide variety of cameras
  7. Compatible with EdgeHD 800 T-Adapter

Celestron’s EdgeHD reducers features a custom 4-element optical design engineered to maintain the flat-field performance of our award-winning EdgeHD optical system. Unlike generic reducers, our premium reducers provide substantial back-focus to accommodate an assortment of imaging accessories.

EdgeHD reducers offer high-index optical elements, including extra-low dispersion, exotic Lanthanum elements, which provide high contrast viewing while minimizing chromatic aberration. All air-to-glass lens surfaces feature multiple layers of coating for maximum light transmission and color correction and contain blacken edges to minimize internal reflection and maximize image contrast.

Incorporating computer assisted CNC machined aluminum housing, for precise spacing and alignment of optical elements, and threaded metal covers on the lens assembly to protect your investment from dust and scratches, our reducers offer you an outstanding mechanical design.

With the Fastar option on all EdgeHD optical systems, coupled with the .7x reducer, your telescope becomes the most complete imaging system available in its price range today.


  • Design: 4-element optical layout designed specifically for the EdgeHD 8" to maintain the flat-field performance of the EdgeHD optical design
  • 105mm of back-focus: Provides generous back-focus to accommodate additional accessories and a wide variety of cameras. Also allows use of existing T-Adapters for EdgeHD 800 and other Celestron imaging accessories
  • One full F-Stop faster than f/10: Reduces the exposure time by one-half to capture the same brightness of object
  • Increase field of view by 43%: Better for capturing wide field images of larger galaxies and nebulae


  • Lanthanum Glass Elements: EdgeHD reducer uses "rare earth" Lanthanum glass elements for clear, high contrast viewing while minimizing chromatic aberration
  • Fully multi-coated lens elements: All air-to-glass surfaces have multiple layers of coating for maximum light transmission and color correction
  • Blacken edges: All lens elements have blacken edges to minimize internal reflection and maximize contrast

Large Illuminated Field

  • Optimized for APS-C sized sensors: Including most DSLR cameras and Nightscape CCD cameras

Mechanical Design

  • Machined aluminum housing: Computer assisted CNC machined aluminum housing for precise spacing and alignment of the optical elements.
  • Threaded metal covers for both ends of the lens assembly: To protect your investment from unwanted dust and scratches.


  • Provides and intermediate focal length between EdgeHD's native f/10 (or f/11) and the optional Hyperstar accessory at f/2, making the EdgeHD the most complete imaging system in its price range
Customer Reviews

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