Under normal guiding circumstances, DEC doesn't move, but we can pulse it to account for cyclic error, or missing polar alignment. When it is pulsed, it is tight against one side of the worm gear or the other, and the motor is stopped again, correct?

The next adjustment would use the full backlash, or no backlash, depending on the direction of the previous adjustment. If the direction is the same as previous, the worm is tight and no backlash should be added to the pulse. If the direction is opposite the last pulse, the full backlash comes into play and should be added before the mount would move the scope. I don't understand why a percentage would be used here. I would rather that the variability is accounted for in the pulse width, and not the backlash, where we already have some ability to set things like aggressiveness. The backlash is fairly fixed for a session I would think. The caveat being a meridian flip where the first pulse might be way off. It could be off by as much as 2x the backlash, but after the first correction, the full or nothing works again.

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