What is the back focus for the ST2000 XCM? I measured 0.3-inches for the adapter plate. I heard both 0.92" and 0.49". I need to know for the Celestron f/6.3 coma corrector. There is no filter wheel on it btw. Edit: I went ahead and removed the face plate and measured it at 17.6mm (including 5.1mm for thickness of the face plate). This doesn't include the 6.9mm for the face plate adapter for screwing on the 2-inch focuser adapter. Including the focuser adapter results in a 24.5-mm backfocus (0.96"). I will leave this up here for anyone else that might need to know.
User manual says 0.92". https://diffractionlimited.com/wp-content/uploads/2016/03/USBmanRev14.pdf - Page 37
