The Nikon D800 has superlative file quality, even at 12-bits, but shooting at 14-bits allows the full quality to be recorded.
The first days of my review, I screwed up by using 12-bit images instead of 14-bit images— so the examples prior to April 16, 2012 can only look better than shown!
I shoot only RAW with all my cameras.
The D800 RAW 14-bit offers tremendous headroom.
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