Well, not so fast. When an FX camera is in DX crop mode, your resultant file is, well, cropped. More precisely, the crop is to the central 40% of the frame - so your 12MP D700 delivers 5.1mp files when operating in DX crop mode. Your D300, of course, yields 12mp files in DX mode.
A D800 in DX crop mode has the same "problem" - so instead of a 36mp file, you'll get... about 16mp. So a D800 in DX crop yields a bit MORE resolution than the D300 does.
If it's not clear, here's a better way to think of DX:
Take your FX camera, and shoot a picture. Print it at 8x12. To see what you would get from DX, cut out the central 5x8 of the 8x12 print. That's what you'll get from the DX camera or an FX operated in DX crop mode.
_____ Brian... a bicoastal Nikonian and Team Member
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