My new D800 has Left/Right AF issues too :(

My claim is a little bit different. A difference of 3 AF Fine tune units is the lowest difference one could measure. Such a body would be perfect. I would require also a perfect lens. I've never met those.

To support what I have say, here is the D800/85mm combination I am talking about. The optimal AF Fine Tune for this lens was: -15 for the left AF sensor, -7 for the middle AF sensor, -3 for the right AF sensor.

First, here it what you get if you turn AF Fine Tune to 0. The focus was always on the horizontal black and write stripes. You can assess the depth of field on the ground.

Without AF Fine Tune: the left AF gives a blurry target (100% crops)

Now, If I set the AF Fine Tune to -10. As you can see, on all these images, the target is quite sharp.

With AF Fine Tune set to -10: all targets are sharp (100% crops)

That's the reason why I believe that shooting flat targets s a waste of time. This procedure with 0 AFFT on this lens would say that there is a problem. The same procedure with -10 AFFT would say that there is no problem. My conclusion is that shooting flat target is a waste of time.

I am quite sure people presenting the shots with an AFFT of -10 would say that there is no difference in between the sensors. They are just wrong. There is a difference as you can see on the ground. The difference is of 12 AF Fine Tune. But it could be considered as acceptable. I have tested 3 D800 and many lenses, and such a difference was found on every single combination. I could be unlucky, but I am quite sure that people who think that their body is "perfect" are just in the second scenario. Nothing better.