wow what a bazooka of a Lense. And a 36mp sensor. Took some time to learn how to change things. It’s got lots of buttons. Shooting a regatta and got this and a te14 and te2 teleconverter.
Photozone.de has a nice technical review. It shows that maximum center sharpness is at f/2.8 but while center declines less than 1% the corners get much better at f/4. Center is an amazing 4013 lph or 24MP true.
With the te14 the best is one stop more or f/5.6
Finally the te20 at f/8
The base ISO is also only 64 for d810 so much lower noise.
Then there is the manual focus Zeiss. So old school but surprisingly easy with Dpreview.com focus assist in the Nikon. Best aperture is f/4 according to reviews.