Starizona Nexus 0.75x Newtonian Focal Reducer/Coma Corrector

Turn your Newtonian telescope into a fast, high-quality astrographic instrument with the Starizona Nexus focal reducer.Newtonian telescopes require a coma corrector in order to give sharp stars over a large field of view, but most coma correctors keep the telescope's native focal ratio or even make the scope slower. The Nexus instead acts as a coma corrector and also provides a 0.75x focal reduction factor. This turns a common f/4 Newtonian into an f/3 system, giving a larger field of view and reducing exposure times by a factor of 1.8x.The Nexus incorporates extra-low dispersion (ED) glass in a sophisticated optical design that gives performance equal to the best coma correctors while decreasing, instead of increasing, the focal length. The Nexus is also designed to be parfocal, so it does not change the original focal point of the telescope. The corrected image circle is 28mm, accommodating camera sensors up to APS format. While nominally designed for the popular commercial f/4