Autofocus Cannot Overcome Mirror Shift with LX200 - Can a new focus point be set manually during an autorun?

Hello! I’ve got a problem with mirror shift that I am unsure how to handle.

As I follow a short period variable star, when it reaches 30 degrees above the western horizon, I slew to the next target at 30 degrees above the eastern horizon. The focus shifts by a relatively large amount so that the new stars are “donuts” on the eastern horizon.

SGPro autofocus seems to give up and return to the focus that I had on the western horizon. The captured images then are significantly out of focus until the new target filed rises to about 45 degrees altitude and a repeat autofocus works.

For example, with Autofocus I use 7 focus spots, each with 7 steps separating them. Inside and outside focus give HFR at about 5 to 6. If I add another focus spot to inside and outside focus (total of 9), the donuts start to become large enough that SGPro seems to have difficulty unless the focus starting position is roughly centered - which does not happen with long slews.

Is there a way to manually tell SGPro to go to a certain focus position when I slew from horizon to horizon in order to overcome such a focus shift? Thank you and best regards.


There is not…but I wonder if something like backlash compensation might help here. Or potentially enabling smart focus.


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