I'm using a NN3 Mk2 with my Canon 7d and have noticed that when calibrating the NNP by aiming down at the bulls-eye on the rotator, my viewfinder center is off to the right a few mm. This is not due to lower arm settings, since that only determines horizontal offset when pointed 90deg down like this. Is this normal? I would have assumed a camera like the 7d would have a dead-center thread. Is it possible that the NN is somewhat off? I've checked my upper arm rotation and it is definitely pointed straight down and level.

From what I can tell, I may need to get the T-adapter to get things exact...but was under the impression that I wouldn't need this when I bought the NN3 starter kit. I've tried 3 different lenses with same results.