Yep, you can perfectly use the 18-200mm on a D700. I used it once on a D3 even in 4:5 crop-mode (which uses 80% of the pixels so you're at 10MP) and it showed various degrees of vignetting. But it was not too bad:
D3 9684 ISO3200 5:4 Crop DX-Lens
, at 170mm, f5.6, 3552x2832
Btw. I allowed me to change the thread title to "DX lens on FX body". that should make your point clearer, Drecked.
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