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Askar F3.9 Full Frame Reducer for FRA400/5.6

Brand: Sharpstar / Askar

SKU : SS-FRA400-REDUCER

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  • Shortening the exposure time on its original 400 focal length and f/5.6 focal ratio design basis
  • Satisfies most deep-sky astrophotography
  • Pictured telescope not included. Buy the telescope here!

Product Details


  • Askar provides a brand-new F3.9 full frame reducer for FRA400 astrograph, further reducing the focal length and thus shortening the exposure time on its original 400 focal length and f/5.6 focal ratio design basis. The reduction factor is 0.7×, and the reduced focal length is 280mm, which can satisfy most deep-sky astrophotography. The back focus is standard 55mm. The reducer has built-in M48×0.75 thread, easy for the attachment of 2" filters.






  • specifications

    Back Focus55 mm
    Camera/Eyepiece ConnectionMale M48x0.75
    Focal Length280mm
    Focal Ratiof/3.9
  • included items

    • Askar F3.9 Full Frame Reducer for FRA400/5.6

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