The way I figure out the backlash setting is bring something into focus more or less.

Use Polynomial focus routine. The focuser will go out 2 times, then go in a few times. I put in a backlash value that lines up the in movement with the two out movements. This may take a few times to get the plots lined up so the backlash is close to the optimal value.

Once you have the back lash setting setup, then you can use any of the other focus methods like Linear 1 pass.

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