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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.
Askar 0.8x Reducer for 140APO
Askar 0.8x Reducer for 140APO

Askar 0.8x Reducer for 140APO

by Askar
SKU ASK-ASKAR140R
$329.00 - $329.00
$329.00
$329.00 - $329.00
$329.00
Price Match Policy!
  • Reduces 140APO Focal Ratio to f/5.6
  • Shortens 140APO Focal Length to 784mm
  • Standard 55mm Back Focus Requirement
  • Triplet Optical Design with Field Flattening
  • Integrated M48 (2-inch) Filter Thread
1 in stock
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Downloads
  • Warranty

  • Askar 0.8x Reducer for 140APO

    The Askar 0.8x Reducer for 140APO converts the telescope into a faster f/5.6 imaging system with a 784mm focal length. This triplet reducer is engineered to maintain a standard 55mm back focus from its M48 male thread, simplifying camera connections. The 0.63kg assembly includes both M54×0.75 and M48×0.75 rear threads, with an integrated M48 filter thread inside for direct filter installation.

    Transforming the 140APO to an f/5.6 Astrograph

    By reducing the native focal ratio of the Askar 140APO to f/5.6, this corrector significantly cuts required exposure times, allowing you to gather more signal in less time. The triplet optical design simultaneously flattens the field for sharp stars across a full-frame sensor, while the shorter 784mm focal length provides a wider field of view for framing large targets like the Andromeda Galaxy (M31) or the North America Nebula (NGC 7000).

    55mm Back Focus and Flexible Connectivity

    Integrating the reducer into your imaging train is straightforward, thanks to the industry-standard 55mm back focus measured from the base of the M48 male thread. The reducer provides both M54×0.75 and M48×0.75 output threads for direct connection to a range of cameras and filter wheels. For added convenience, an internal M48×0.75 filter thread allows you to install 2-inch filters directly into the reducer itself, minimizing the components in your optical path.

  • How does the Askar 0.8x Reducer change my field of view on the 140APO when imaging the Orion Nebula (M42)?

    The reducer shortens the 140APO's focal length to 784mm, widening your field of view significantly. This allows you to capture the entire Orion Nebula complex, from the Trapezium Cluster to the fainter outer loops, in a single frame with a full-frame camera, which is difficult at the native focal length.

    I use an APS-C camera with my Askar 140APO. Is this reducer still a good choice?

    Yes. While designed to illuminate a full-frame sensor, the 0.8x Reducer provides excellent field flattening for smaller APS-C sensors. The main benefit is the speed increase to f/5.6, which reduces your sub-exposure times regardless of sensor size, helping to improve your signal-to-noise ratio on faint targets.

    What is the back focus for the Askar 140APO 0.8x Reducer?

    The required back focus is a standard 55mm, measured from the base of the male M48x0.75 thread to your camera's sensor. This is compatible with most DSLR/mirrorless cameras using a standard T-ring and many dedicated astronomy cameras with their included spacers.

    Can I use 2-inch filters with the Askar 0.8x Reducer?

    Yes, the reducer has a built-in M48x0.75 filter thread on the camera side. This allows you to screw a standard 2-inch filter directly into the reducer housing, placing it securely within the optical path.

    How does this reducer attach to the Askar 140APO telescope?

    The reducer is designed to thread directly onto the focuser of the Askar 140APO for a secure, tilt-free connection, ensuring perfect optical alignment.

    What is the optical design of the Askar 140APO 0.8x Reducer?

    The reducer uses a triplet (3-element) air-spaced optical design. This configuration allows it to both reduce the focal length and correct for field curvature, providing sharp stars across the entire image field.

  • Reduced Focal Ratio f/5.6
    Reduced Focal Length 784mm
    Optical Design Triplet
    Back Focus 55mm (from base of M48 male thread)
    Camera Side Threads M54×0.75 & M48×0.75
    Internal Filter Threads M48×0.75 (2-inch)
    Weight 0.63 kg

    • Askar 0.8x Reducer for 140APO

      × 1

    • Front Dust Cap

      × 1

    • Rear Dust Cap

      × 1

  • Askar 1-Year Warranty