I'm with Roger and Brian on this: actually, looking at your first image, there is a significant in-focus zone there - but at f/2, it's bound to be really more shallow than what you would get at the same aperture and field of view on a DX sensor such as the one in the Pentax cameras.
Looking at the f/8 and f/11 versions, I can't find anything wrong with them at all, they seem quite in-line with what one should/could expect from a D700&50/1.8 combo... A combo I have the joy to have and use, actually!
So I'd stongly suggest you review your settings for AF and in-camera sharpening, or if you shoot raw (.nef), the amount of sharpening you apply: you may have been a tad conservative in that respect, although even at 2048 pixels I can't really say it's lacking!
Hope this helps
Olivier Rychner __________________________________________ Jetez un oeil à ma galerie if you feel like it! And it's a bit void as of now, but I also have a Nikonians blog
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