Thanks again for your patience explaining all that. If I understand that approach correctly it requires the ability to measure the actual focus position, which is pretty hard to do on an SCT. I may be able to determine that backlash of the focuser motor unit, but that would not include any backlash of the focus unit within the SCT itself (which is probably the main contribution to the total backlash).

I guess the main other option may be to try assessing the backlash from the number of ticks that don‘t have an impact to a stars hfr. Perhaps I will try that with a somewhat defocussed bright star, where changes should be very visible.

I don‘t know if an overshoot approach actually works better. It is just what I had seen users of some other software platforms recommending. If I don’t succeed in finding the proper backlash setting I probably can still fall back to the "linear" algorithm, which appears to be the most recommended approach for ekos.

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