I've seen a lot of calibration videos which show quite a few ways to do it. What I want to know is are they all ok to use. I believe it does not matter weather you use clockwise or anticlockwise. What I am curious about is weather it also does not matter if you rotate the phantom on its own axis with your hands while standing still or weather you hold it out in front of you and turn yourself around in a circle? The second way looks easier to do.