#16. "RE: Is it just my bad luck, or, Does the D800 still not focus?" In response to In response to 15
I believe one of the other members using FoCal found that the increased resolution of the D800 allowed it to show more focus error - the center was so sharp that it allowed a higher level of resolution - and normal performance at the edges was worse in comparison to the center.
I don't think FoCal is ready to support using the numerical values to compare cameras or lenses. But it should give you a good indication of performance and how fine tuning should be adjusted.
There is definitely an art to interpreting the results. FoCal produces a lot of information and is a good tool. Having a bit of context from different lenses and camera bodies should be helpful.