I shot Spyder LensCal with my DSLR and favorite lens. I then set the autofocus compensation in my camera the same number of units as the ruler indicated (in my case negative one). But this did not correct my autofocus, its still off.
The units on the Spyder LensCal ruler give you an orientation on how to set the micro adjustments on your camera. Depending on the focal length of your lens it will result in a different relation, but you will see that it’s easy to adapt this to your needs. You may find it necessary to test multiple adjustments in the indicated direction in order to determine just how much to adjust your camera’s autofocus compensation. Perhaps two units in your autocalibration compensation might equal one unit on the ruler; a bit of testing will indicate this.