As stunning as the TEC APO140 is, this comparison is to demonstrate the effect on resolving power and the MTF (improved contrast transfer function). Both images below were taken with the same camera, exposure time and temperature (SBIG ST-8300M, 5 minutes at -10c). The TEC-APO140 version was imaged unbinned yielding a scale of 1.14 arc-seconds/pixel whereas the EdgeHD 9.25 version was binned 2x2 yielding 0.95 as/p.