I have a problem: Back-focus of my lens is not constant so it is not possible to calibrate it using AF fine tuning.
I have body Nikon D7000 and the lens is Nikkor 50mm f/1.8 D. I've bought the lens already used. I was able to calibrate back-focus using AF fine tuning to focus distance about 2 meters (for a head only portraits), but when I want to focus to about 6m (whole figure), it has back-focus of about 20cm.
- Is this normal behaviour of back-focus or should it be constant in all focus distances (and apertures?)
- Is it possible to calibrate this in a service?
- I'm thinking about buying a new lens: Nikkor 50mm f/1.8 G, this problem shouldn't reappear, am I correct?
PS: My D7000 body had shown back-focusing problem even on 18-105mm it was sold with (and few other lenses i've tried), but all was within the range of AF fine tuning and could be fixed.