I have a permanent setup in an observatory, and I am trying to get it fully automatic. I recently started using SGP's autofocus, and have it calibrated for good results. However, the autofocus needs the camera to be close to good focus before it starts. How do folks ensure that?
I could go out to the observatory and do a Bahtinov mask manual focus, but I want to get away from manual intervention, especially if it requires my physical presence.
I could do a manual focus remotely without the mask. That worked last night, but I still want to get away from manual intervention, in case I want my session to start at 3:00 am.
I hoped that the focus would hold from one session to the next, but it didn't. The focuser seemed to have slipped between sessions.
So, I am looking for ideas to establish focus at the beginning of a session. The best I can think of right now is to lock the focuser in the morning when I install the covers, and hopefully remember to unlock it when I remove the covers for the next session. The ultimate solution is to replace the Crayford with a rack and pinion, but that's expensive: I'd need a new focus motor, too.