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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.
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.
Sky-Watcher Esprit 70EDX / Evostar 100EDX Flattener

Sky-Watcher Esprit 70EDX / Evostar 100EDX Flattener

by Sky-Watcher
SKU SW-S20216
Sold out
$220.00 - $220.00
$220.00
$220.00 - $220.00
$220.00
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  • 0.92x Reducer/Flattener
  • Compatible with the Esprit 70EDX and Evostar 100EDX
  • 44mm Image Circle for Full-Frame Sensors
  • Esprit 70EDX: 490mm f/7 to 450mm f/6.4
  • Evostar 100EDX: 700mm f/7 to 644mm f/6.4
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  • Description
  • FAQ
  • Specifications
  • In the Box
  • Warranty

  • Sky-Watcher Esprit 70EDX / Evostar 100EDX Flattener

    The Sky-Watcher Esprit 70EDX / Evostar 100EDX Flattener is a 0.92x reducer/flattener that corrects the natural field curvature of both telescopes and delivers a flat field across a 44mm image circle. It also slightly shortens the focal length, bringing both scopes from f/7 to f/6.4 for faster imaging.

    44mm Flat Field for Full-Frame Sensors

    Without a flattener, stars at the edges of a large sensor turn into elongated shapes because a refractor's focal plane is curved. This flattener corrects that curvature across a 44mm image circle, wide enough to cover the diagonal of a full-frame sensor, so stars stay point-like from the center to the corners.

    0.92x Reduction: f/7 to f/6.4

    The 0.92x reduction speeds both telescopes from f/7 to f/6.4, which shortens the exposure time needed for the same signal by about 15% and slightly widens the field of view.

    • Esprit 70EDX: 490mm at f/7 becomes 450mm at f/6.4.
    • Evostar 100EDX: 700mm at f/7 becomes 644mm at f/6.4.

  • Which telescopes does this flattener fit?

    Sky-Watcher lists it for two telescopes: the Esprit 70EDX Super APO Triplet and the Evostar 100EDX APO Doublet. For the Esprit 100EDX, use the dedicated Esprit 100EDX Flattener (S20217).

    Will it cover a full-frame camera?

    Yes. The 44mm image circle is larger than the roughly 43mm diagonal of a full-frame sensor, and it covers APS-C and smaller sensors with room to spare.

    Does it reduce the focal length?

    Yes, slightly. It is a 0.92x reducer/flattener, so the Esprit 70EDX goes from 490mm to 450mm and the Evostar 100EDX from 700mm to 644mm, both at f/6.4.

    What back focus does the flattener need?

    Sky-Watcher had not published the back focus specification for this flattener at launch. Contact us before ordering and we will confirm the correct sensor spacing for your camera.

  • UPC 810098970754
    Optical Specifications
    Type Reducer/Field Flattener
    Reduction 0.92x
    Image Circle 44mm
    Compatibility
    Compatible Telescopes Esprit 70EDX, Evostar 100EDX
    Esprit 70EDX with Flattener 450mm at f/6.4
    Evostar 100EDX with Flattener 644mm at f/6.4

    • Esprit 70EDX / Evostar 100EDX Flattener

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  • Sky-Watcher 2-Year Limited Warranty