Sky-Watcher 0.85x Reducer / Corrector / Flattener for 100ED Black Diamond

Description

This accessory is necessary because the refractors (glasses) provide a curved focal plane, the stars are not point near the edges. The reducer / corrector provides a corrected image to the edge of the field. Screws directly to the bezel's crayford (M56 thread). Optimized for Sky-Watcher 100ED f / 9 Black Diamond (Doublet) lenses, this screw-in reducer / corrector reduces the telescope's focal length by a factor of 0.85x (induced focal ratio of f / 7.65).

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 . Not suitable for Sky-Watcher ESPRIT 100ED (triplet) lenses.

M56 female at the front

M48 male at the rear

55mm backfocus