Sky-Watcher Quattro Imaging Newtonian Coma Corrector

The necessary companion for the Quattro Imaging Newtonians to achieve true professional images. The inherent problem with reflectors is coma as you start to get away from the center of the field.  So, to get rid of that particular aberration you will need a coma corrector like this one for your instrument.  This Sky-Watcher coma corrector will bring your Quattro imaging to the next level and deliver stunning wide field views with pinpoint star to the edge. Four-element, f/4.  FPL51 and Schött glass.  Optimized for Quattro imaging Newtonians.  Requires 55mmback focus.  Can handle up to full-frame sensors.  Does not add magnification.  48mm threads. Tech Details: Focal Ratio f/4 Optical Coatings FPL51 ED and Schott Glass Back Focus 55mm