Originally Posted by MaximusJ
Everybody who are micro adjusting their focus are doing it by trial and error?
With Canon and a long lens, you simply set your camera up on a tripod, focus on something 20 or 30-ft away, then switch to Live View, 10X, then refocus (AF both times) to see if the focus changes. If it changes, then you dial in some correction and recheck all over until you get equally good focus by both methods.
Canon uses a different AF method in Live View vs. viewfinder, but I can't remember the details of why this simple test works. (It does, I've tried it). Of course, if neither will focus tack sharp, then you've got a problem.
Anyway, try that technique before buying a calibration devise. Also, remember to do it with your TCs on the lens also. As long as they're Nikon brand, I think the camera, like Canon, will recognize the TC in use and adjust in combination with the lens.