These are not great wildlife images but I was pushing here to find out what I have. Difficult conditions for any camera. A dark bird, in the shadows, with lots of branches to grab focus and relatively high ISO. All taken from the same 23.7 meters with the same settings and the same quick pp in LR with 0 noise reduction and 0 crop. 1/800, f6.3, auto ISO 2200+-, +1 ev, 1.4III + 500mm f4 E, D850. I am thinking that for wildlife I may experiment with the 5:4 and 1:2 crop factors. I still get considerably more information than with the D500 but don't have to crop as much and don't have such large files to deal with vs shooting FX and cropping. The 1:2 looks especially promising @ 31.5mp and a 30x20 image area ( think 4 x 6 and 8 x 12 ). In this experiment DX produced the least pleasing image.