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The coma is an imaging defect in which the diffraction image of stars which are located on the edge of the field of vision appear to have a comet-like tail (coma). The stars do not appear as point-shaped, but instead are elongated and distorted. The coma corrector compensates for this error.
Designed for Vixen's R200SS Newtonian Reflector telescope, this high quality corrector lens system eliminates aberration from parabolic mirror surfaces.
The corrector delivers sharp pinpoint star images to the edge of the field of view. A Wynne type 3-element in 3- group optical design corrects coma aberration for parabolic mirrors. A broad 44mm diameter circle, which covers a 36mm x 24mm full frame DSLR, and delivers sharp images over the entire imaging field. A large 50mm aperture lens allows for ample edge of field illumination. The same anti-reflective AS coatings, which are used in Vixen's high end VSD 100f/3.8 Astrograph, are used to take advantage of 99.9% superb high light transmission.
Loss of light and ghost flare images are eliminated due to the complete matte finish inside the corrector.
Rigorous quality control assures you of high performance.