You have a D700

  • Like what you've gotReconsider. The D750 produces better looking images than the D700, all else equal; and the D850 raises the pixel bar substantively. The real issue with going from D700 to D750 is the trade-off in body controls and quality. 
  • Dislike what you've got: consider upgrading. You really only have two logical choices if sticking with FX DSLR: the D750 or D850. Frankly, I’d say that really is only one choice: the D850 is more the camera you’re giving up than the D750. But you’re leaping a lot of ground here in pixels, focus, features, and more. Still, it’s the ground you want to leap: get the D850 if you need to upgrade. But I'd argue that the D700 user today should probably take a close look at the Z6: it's more of a performance camera than the D750 (e.g. 12 fps). 
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