Designed by Dave Rowe, the Alpine Astronomical Baader Rowe Coma Corrector helps to solve a common problem with Newtonian reflectors. Designed for fast f/3.5 to f/6 optical tube assemblies (OTAs) and optimized for f/4s, the triplet lens design and Phantom Coating Group anti-reflection multi-coatings maximize light throughput and correct off-axis comas to produce bright and sharp views. This is especially useful for astrophotography. While the corrector adds an additional 91.5mm back focus, unlike conventional correctors, it does not rely on Barlow-style magnification increases to correct comas. Instead, the lens system does the correction so magnification and focal ratio are unaffected.
The corrector's extra back focus provides plenty of room for filter wheels, off-axis guiders, and camera autoguiding. It is made to fit larger 2" focusers and drawtubes to accommodate today's imaging sensors, with front threads for 2" eyepiece filters and standard male T-threads on the other side for T-rings and the direct connection of other accessories. Finally, a stop-ring is provided to give users control of the depth placement of the corrector for precision imaging results.