The coma corrector is a very important accessory for all NEWTONS with a focal ratio from F/6.0 to F/3.5; it allows you to correct the field even with cameras equipped with large sensors, up to FULL FRAME format.
On the inside (camera side) there is a thread for connecting 2" (50.8mm) filters, such as a narrow band filter or a light pollution filter.
It will thus be possible to reduce the focal length of your Newtonians, for example a Newtonian with a native focal length of F/4.0 will be reduced to a resulting focal length of F/3.4.
Coma is an optical aberration that derives its name from the classic comet-like appearance of images created by optical systems that assume this defect.
Coma occurs when the imaged object is displaced laterally with respect to the axis of the system by a certain angle. Rays that pass on the periphery of the optical axis are focused at a different point on the axis, further away if the coma is positive or closer if the coma is negative.
A beam of rays passing through the lens at a certain distance from the center, are focused into a ring shape on the focal plane, the superposition of these different rings creates a V shape similar to the tail of a comet.
As with spherical aberration, coma can be reduced or eliminated by using appropriate coma correctors for the optical system involved.
Compatible with Newtonians from 150mm to 300mm aperture, focal ratio between F/3.5 and F/6.0
Magnification factor: 0.85x
Correct field: FullFrame
Optical elements: 4 optical elements with multi-surface coating
Outer diameter: 3" (76.3mm)
Back focus: 55mm
Total length of the corrector: 119.81mm
Weight: 0.89kg
