One of the optical distortions that can be seen in Newton's optical tubes is called a coma. Reduce image quality, blur and blur edge details, and reduce field of view. This aberration is most strongly manifested in high-aperture (f / d) and "fast" parabolic optical tubes.
To remedy this defect, this 50.8mm flux corrector, optimized for f / 5 Newtons (not f / 4), will allow you to obtain point stars at the edge of the field, both visually and in photography. , makes the image clearer across the entire field of view and does not affect the focal length or magnification of the optical system.
For the photo, you will need to use an M48 wide field T-ring dedicated to your camera, available for Sony, Nikon or Canon
2 "(50.8 mm) male at the front
M48x0.75 male at the rear
1 Sky-Watcher Coma Corrector for Newton
1 short adapter ring (replaces the original crayford)
1 x 50.8mm sliding eyepiece holder