When I had centering problems, I just played around with the centre pixel values. I dunno if it was the best solution, but it worked pretty well
! I thought that was the problem for us when the camera was looking about 10 degrees off from the light.
Ah, sorry I didn't see you were talking about your turret, not your camera. Well, maybe it might help others, so I will leave it here. Our camera wasn't centered on the green light. It was strange.