Nikon D850 Experience Report: AF Fine Tune, Focusing Precision, Accuracy with the Nikon 14-24mm f/2.8G + Focus Shift Behavior
This page supplements and extends the Nikon 105mm f/1.4E assessment, but in this case taking a hard look at focusing precision and focus shift and whether AF fine tune is of value. It also looks at the best performance that can be obtained from f/2.8 through f/8 by focusing manually at each aperture, avoiding focus shift.
This is a very in-depth study. I urge anyone shooting a high-res DSLR or the Nikon 14-24/2.8G to study the serious problems that are seen here, because these sorts of things can happen with other lenses too. I do not hold the D850 responsible in this case, but nevertheless it shows that it is not safe to assume much about AF precision regardless of how advanced a camera is. It also shows just how damaging focus shift can be to sharpness.