petego4it wrote:
to FTN just to clarify, it isn't that my shots are "soft" with auto focus, it is that you cannot i.d. what is in them at all, total blur and continual hunting. Clearly the camera is trying hard to focus but is "lost". I will try the reset to factory spec and blow out the innards before taking to Nikon per other ideas here, thank you.
OK. Sorry for the misunderstanding. Is your D850 still under warranty? If so I would call Nikon and see what they suggest you do. Even if it isn't I would give then a call before you try anything.