Sky-Watcher 0.85x Reducer / Corrector / Flattener for 72ED

Description

This accessory is necessary because refractors (lenses) provide a curved focal plane, the stars are not actually point near the edges in the image. The reducer / corrector provides a corrected image to the edge of the field. A specific adapter will allow you to fix the reducer / corrector on the Crayford of your glasses. Optimized for Sky-Watcher EvoStar 72ED f / 5.8 (Doublet) lenses, this screw-in reducer / corrector reduces the telescope's focal length by a factor of 0.85x (induced focal ratio of f / 4.93).

The use of a focal reducer in astrophotography also reduces the exposure time. You will need to use an M48 wide field T-ring dedicated to your camera, available from Sony, Nikon, or Canon.

CAUTION . The corrector / reducer is the same as for the Sky-Watcher 80ED bezel (this explains the engraving of the model with the information ED80 and not ED72) but to use it with the Sky-Watcher bezel 72ED, you must use the adapter ring provided.

M56 female at the front

M48 male at the rear

55mm backfocus