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July 1st: Store will be closed for Canada Day. Orders placed that day will ship on July 2nd.
Celestron Reducer Lens .7x - EdgeHD 800
Celestron Reducer Lens .7x - EdgeHD 800
Celestron Reducer Lens .7x - EdgeHD 800

Celestron Reducer Lens .7x - EdgeHD 800

by Celestron
SKU CEL-94242
$419.00 - $419.00
$419.00
$419.00 - $419.00
$419.00
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  • Reduces focal length by a factor of 0.7x, changing the EdgeHD 800 from f/10 to f/7
  • 4-element optical design maintains the native flat-field performance of the EdgeHD system
  • Increases the field of view by 43%, ideal for capturing large celestial objects
  • Provides a generous 105mm of back focus for compatibility with a wide range of cameras and accessories
  • Fully multi-coated optics with Lanthanum glass elements maximize light transmission and minimize chromatic aberration
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Downloads
  • Warranty

  • Celestron Reducer Lens .7x - EdgeHD 800

    The Celestron Reducer Lens .7x for the EdgeHD 800 is a custom-engineered 4-element optical accessory that transforms the telescope's native f/10 system into a faster f/7 instrument. This 0.7x compression factor increases the field of view by 43%, allowing you to capture expansive nebulae and galaxies within a single frame. The design provides a substantial 105mm of back focus, accommodating complex imaging trains with filter wheels, off-axis guiders, and a wide variety of dedicated astronomy cameras.

    A 4-Element Design for Flat-Field Imaging

    Unlike a generic reducer, the Celestron .7x Reducer is engineered specifically to work with the EdgeHD 800's optical system. Its 4-element design, which incorporates high-index Lanthanum glass, maintains the flat-field, coma-free performance the EdgeHD is known for, ensuring sharp stars from the center to the edge of the frame. All air-to-glass surfaces are fully multi-coated to maximize light transmission and eliminate chromatic aberration, preserving the high-contrast views of the original optical design.

    A 43% Wider Field and 0.7x Faster Exposures

    By reducing the focal length, this accessory widens your field of view by 43%, making it possible to frame large targets like the Andromeda Galaxy (M31) or the Orion Nebula (M42) in their entirety. This focal reduction also makes the optical system one full f-stop faster, cutting required exposure times in half. You can gather the same amount of signal in a 5-minute sub-exposure as you would in a 10-minute exposure at f/10, reducing demands on your mount's tracking and minimizing noise.

    CNC Machined Housing and 105mm Back Focus

    The reducer's housing is CNC machined from aluminum for precise optical alignment and spacing, critical for maintaining image quality. A key feature is the generous 105mm of optimal back focus, measured from the reducer's rear flange. This provides ample room for accessories like off-axis guiders, filter wheels, and adaptive optics systems without compromising the flat-field correction, a significant advantage over reducers with shorter back focus requirements.

    The f/7 Midpoint for the EdgeHD 800

    The .7x Reducer gives your EdgeHD 800 a versatile f/7 focal ratio, creating a three-in-one imaging platform. This provides a crucial intermediate step between the telescope's native f/10 for high-resolution planetary and small galaxy imaging, and the ultra-fast f/2 ratio available with the optional HyperStar accessory for wide-field surveys. This flexibility makes the EdgeHD 800, equipped with the .7x reducer, one of the most complete imaging systems available.

  • What does the 105mm back focus on the EdgeHD 800 Reducer mean for my imaging setup?

    The 105mm back focus is the required distance from the reducer's rear mounting flange to your camera's sensor for optimal flat-field performance. This generous distance allows you to easily install accessories like an off-axis guider (OAG), filter wheel, and various adapters in your imaging train while still hitting the correct spacing.

    How does the .7x Reducer help when imaging the Andromeda Galaxy (M31) with an EdgeHD 800?

    At its native f/10 focal length, an EdgeHD 800 is too magnified to capture the full Andromeda Galaxy. The .7x Reducer increases the field of view by 43%, allowing you to frame the entire galaxy and its companions, M32 and M110, in a single shot with an APS-C or smaller sensor. It also reduces exposure time, making it easier to capture the faint outer dust lanes.

    Will this reducer work with a full-frame camera on my EdgeHD 800?

    While the EdgeHD 800 optical tube has a 42mm illuminated image circle capable of covering a full-frame sensor, using this 0.7x reducer will shrink the optimized image circle to 26.7mm. This is ideal for APS-C sensors (like those in many DSLRs) and smaller dedicated astronomy cameras, but it will cause significant vignetting on a full-frame sensor.

    Is the Celestron .7x Reducer better than a generic focal reducer?

    Yes. Generic reducers are not designed to correct for the specific field curvature of the EdgeHD optical system. The Celestron .7x Reducer uses a custom 4-element design to maintain the flat, coma-free field across the entire image, ensuring sharp stars to the corners where a generic reducer would show distortion.

    How much faster is imaging with the EdgeHD 800 Reducer?

    The reducer changes the telescope's focal ratio from f/10 to f/7. This is one full f-stop faster, which means it cuts the required exposure time in half. For example, a 10-minute exposure at f/10 can be achieved in just 5 minutes at f/7 with the same image brightness.

    Do I need any special adapters to connect my DSLR to the .7x Reducer?

    Yes. You will need a T-ring for your specific camera brand (e.g., Canon, Nikon) and a T-adapter that provides the correct spacing to achieve the 105mm back focus. Celestron offers T-adapters designed for the EdgeHD series that simplify this process.

  • Optical Design 4-element
    Compression Factor 0.7x
    Lens Elements 4
    Glass Types Lanthanum Elements
    Optical Coatings Fully Multi-Coated
    Optimal Back Focus 105mm (4.13")
    Image Circle 26.7mm (with reducer)
    Weight 0.8 lbs (0.36 kg)

    • Reducer Lens .7x - EdgeHD 800

      × 1

    • Threaded Metal Dust Cap (Front)

      × 1

    • Threaded Metal Dust Cap (Rear)

      × 1

  • Celestron 2-Year Warranty