Backlash.
If enabled
When a move to a new position occurs and is in the opposite direction to the previous move
lets say current position is 4000 and move is to 5000 and the previous move was IN, then backlash will be applied if enabled
Backlash is applied (the number of steps to move) BEFORE the move is done. This does NOT change the focuser position as it it taking up the backlash in the gears getting ready to move - the draw tube would not have moved - so neither has the actual position - backlash is taking up the slack
Once backlash is done then the move is performed - in this instance from 4000 to 5000.

Adding backlash to the final position would be a mistake - Assuming 4000 to 5000 with backlash of 200, that would make the position 5200 - but technically the focuser is at 5000 because for the 200 backlash steps the drawtube did not actually move, hence myfp2 does not do it that way

Regards
Robert

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