Celestron Focus Motor binding only in SGP


Background: I have my focus motor (94155-A) connected to my mount (CGEM) via the AUX port. The mount is connect to the computer via CPWI. Both are connected in SGP (via “CPWI Focuser” in focuser dropdown).

Sequence Generator Pro is OFTEN unable to successfully drive the focus motor. SGP will command the motor to drive to a position, but the motor seems to stall a few ticks away from the position. At first I thought that the motor was binding, but the problem persisted after re-installing the motor. More importantly, CPWI’s control panel for the focus motor is able to move the motor to position with no problem – it even has no problem “un-binding” the motor if it gets “stuck” in SGP.

The CPWI control panel seems to drive the motor in a very different way (overshoot for backlash compensation, etc.). Is it possible to have the Focuser Driver that external software uses act the SAME as the control panel in CPWI? Enabling backlash compensation in SGP doesn’t seem to help – and in fact seems to make the problem worse.

Any ideas?

SGP doesn’t have a lot of insight in how the focuser is moved. We communicate with the ASCOM driver and say “Move to 1200” and that’s quite literally it. From there it’s up to the driver to get it there. Maybe test the behavior outside of SGP (but still using the ASCOM driver) in the ASCOM Device Hub and see if the results are the same.