I think my D810 hasn't issues with AF, because with all the others my AF lenses, to infinity, the results are perfect. My 85mm at portrait-distance, is great-performer, is very sharp. However, I noticed the tha MAF with the central sensor of MAF is perfect, precise, while sometimes it isn't perfect, it is indecided, uncertain , with lateral sensor, BUT ONLY WITH THE 85mm, also in good light conditions.....