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IMPORTANT: Our store is located in Canada. All orders that include products manufactured outside of Canada or USA will be subject to tariffs and duties, regardless of the order value. US customers are responsible for all applicable duties and tariffs, and those will be billed by the carrier, except for the Lacerta upgrade kit, for which we collect them at checkout.
ZWO FF80 APO 0.76× Full Frame Reducer

ZWO FF80 APO 0.76× Full Frame Reducer

by ZWO
SKU ZWO-F80RE
$249.00 - $249.00
$249.00
$249.00 - $249.00
$249.00
Price Match Policy!
  • 0.76x focal reduction factor
  • Designed for the ZWO FF80-APO Refractor
  • Triplet optical design with one ED element
  • Standard 55 mm back focus
  • Integrated M48x0.75 thread for 2" filters
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Downloads
  • Warranty

  • ZWO 0.76x Full-Frame Reducer for FF80-APO Refractor

    The ZWO 0.76x Full-Frame Reducer is the factory-matched optical modifier for the FF80-APO refractor, shortening its focal length for wider fields and faster data acquisition. Its 3-element optical path uses one ED glass element to maintain the APO's sharp, high-contrast performance across a full-frame sensor. With a standard 55 mm back focus and integrated M48x0.75 threads for 2" filters, this 3" reducer integrates seamlessly into common imaging trains.

    0.76x Reduction for Wider, Faster Imaging

    By reducing the FF80-APO's native focal length by a factor of 0.76x, this accessory dramatically expands your field of view. This allows you to frame large targets like the Andromeda Galaxy (M31) or the Heart Nebula (IC 1805) in their entirety. The reduction in f-ratio also concentrates incoming light, significantly cutting down the required exposure time for each sub-frame and letting you capture more data in a single night.

    Triplet ED Optics for Edge-to-Edge Correction at 55 mm

    A simple reducer can compromise the performance of a high-end refractor by introducing chromatic aberration and coma. This ZWO reducer employs a sophisticated triplet lens design with one Extra-low Dispersion (ED) glass element to counteract these effects. The result is a flat, well-corrected field with sharp stars to the edge of a full-frame sensor, preserving the apochromatic correction of the FF80-APO. The design achieves this correction while maintaining the industry-standard 55 mm back focus, ensuring compatibility with DSLRs, mirrorless cameras, and dedicated astronomy cameras with filter wheels.

    Integrated M48x0.75 Threads for 2" Filters

    The reducer features a built-in M48x0.75 female thread on the telescope side, allowing you to directly mount any standard 2" filter. This provides a secure, tilt-free way to incorporate nebula or light pollution filters into your optical train. Placing the filter inside the reducer body optimizes the light path and often helps achieve focus with accessories that have tight spacing requirements.

  • What does the ZWO 0.76x reducer do for my FF80-APO?

    It reduces the telescope's focal length, which has two primary benefits. First, it creates a wider true field of view, allowing you to fit larger deep-sky objects into your frame. Second, it creates a faster focal ratio, which reduces the exposure time needed to capture faint details, letting you gather more data in less time.

    Is the back focus fixed at 55 mm with the FF80 reducer?

    Yes. The optical design is optimized for a precise 55 mm distance from the reducer's rear mounting flange to your camera's sensor. This is a standard spacing for most dedicated astronomy cameras and for DSLRs/mirrorless cameras using a standard 48 mm T-ring.

    How does the reducer's triplet ED design improve my images?

    The triplet design, which includes one Extra-low Dispersion (ED) element, is corrective. It ensures that the wider, faster image remains sharp and free of false color (chromatic aberration) from the center to the corners of the field. It preserves the high-quality apochromatic performance of the FF80-APO telescope itself.

    Can I use 2" filters with this ZWO reducer?

    Yes. The reducer has a built-in M48x0.75 female thread, which is the standard for 2" astronomy filters. You can thread your filter directly into the reducer body for a secure connection.

    How does this 0.76x reducer help when imaging the Andromeda Galaxy (M31) with the FF80-APO?

    The Andromeda Galaxy (M31) is a very large target, spanning about 3 degrees of the sky. The 0.76x reducer widens the FF80-APO's field of view enough to frame the entire galaxy, including its faint outer arms and satellite galaxies M32 and M110, in a single shot with a full-frame camera.

    Will the FF80 reducer be useful for large emission nebulae like the North America Nebula (NGC 7000)?

    Absolutely. For sprawling H-alpha targets like the North America Nebula (NGC 7000), the 0.76x reducer is essential. It allows you to capture the full extent of the nebula and the adjacent Pelican Nebula (IC 5070) in one frame, while the faster focal ratio significantly reduces the long exposure times typically required for narrowband imaging.

  • SKU ZWO-F80RE
    Optical Design 3-Element (Triplet) with one ED element
    Reduction Factor 0.76x
    Compatible Telescope ZWO FF80-APO Refractor
    Back Focus 55 mm
    Barrel Size 3"
    Filter Compatibility M48x0.75 thread for 2" filters

    • 0.76x Reducer for FF80-APO

      × 1

    • Front Dust Cap

      × 1

    • Rear Dust Cap

      × 1

  • ZWO 2-Year Limited Warranty