Has anyone here used a focal reducer with a secondary mirror focuser? Or is this considered not ideal? For context I've got an RC12, with a focal reducer (.67), and an off-axis guider, and I'm having some trouble getting them all to play together. Often times auto-focus software has trouble at the bottom of the V (it bounces up and down before curving back up, making it look like a v with a flat bottom), and I can't seem to get the OAG to focus either.
It might be as simple as my collimation and backspacing is out enough to cause these issues, but wanted to get thoughts/experience before I spend more nights on this. My worry is that the secondary mirror focuser, in combination with the reducer, changes the spacing needed for the OAG. Meaning I'd need a motorised OAG to keep up. Or maybe it's best to just ditch the reducer.
The distance for back focus is entirely separate and NOT associated to the focus or the focuser's motion.
The distance from the sensor to the reducer/flattener needs to be fixed. Usually 55mm but can be other distances depending. Also the distance from the reducer/flattener to the sensor on the OAG needs to be the same. You can end up with odd shaped stars from the OAG not being in perfect alignment but it shouldn't bother guiding if PHD2 can still identify a core.
