Alfred, I have done that, and it takes care of the focuser's backlash. But what I was talking about is the slight primary mirror tilt I get when the focuser moves it outward. I have found that my images suffer from very small tilt when the focuser ends it's movement outward. Fortunately EKOS ends it's movement INWARD, which is great, but it overshoots the ideal calculated spot forcing me to backup and move the focuser outward to the best focuser position. That adds the tilt. So I have to first go outward quite a ways, and then back inward to straighten the primary.

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