D600 . AF in tungsten light

Sounds quite serious to have a value difference of 15. I'm pretty sure that the warmness of the light also affect the severity of the problem so all is not abnormal. Anything below 2800k should result it horrendous back-focus, the problem will also accentuate as the focus distance increases.

As of now the best we can do is to take sample images and seek address at the service centre. In singapore the technician has agreed to do an in-depth test with my D600 (a rather new serial, 3 weeks old) after next week. He has also agreed to test it under 3200k tungsten light.