How do you calibrate lenses that do not have hard stops?

One way to calibrate photography lenses or any lenses without hard stops is to perform the automatic calibration but manually stop the lens with the motor attached at the Minimum and Maximum to help it register those points, this will not damage the motor or the lens, it should not take much force. If for some reason the motor does not stop at your hard stops or when held at the min or max manually there is something wrong and you should stop immediately to avoid any damage.

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