I've made a preliminary analysis of the Nikon D3's dynamic range,
using the Nikon D3 raw samples posted here:
http://aaronlinsdau.com/gear/articles/d3.html
The latest build of the raw converter dcraw can indeed understand D3
raw files though it seems there are some bugs with some of the
conversion options, the -D option doesn't seem to work; but I was able
to get a linear 16-bit conversion without bayer interpolation that I
could analyze. I should stress that it is important to take the raw
converter out of the equation as much as possible or else you are
testing the raw conversion software as much as the camera. The
linear conversion w/o bayer interpolation does that; to be specific
the options used were
dcraw -v -h -4 -T -k 0 -H 1 -o 0 -r 1 1 1 1 filename.nef
Looking at the ISO 200 sample, I analyzed a few regions of the image
in the red and blue channels, measured the noise in IRIS and
extrapolated the result to vanishing luminance. The dynamic range
seems to be about 11.7 stops (read noise is about 4.9 in 14-bit raw
levels, and the highlights clip at 16383 in those units).
I had to extrapolate down to zero raw level from a bit above since
Nikon clips their blackpoint and so the noise is not a Gaussian
distribution but a half-gaussian at the bottom end, and fluctuations
are thereby clipped as well; using the absolute lowest exposure levels
underestimates the noise.
This is a *very* rough, preliminary measurement. A proper measurement
would use a blackframe image, shot at a high shutter speed with a lens
cap on the body. That will take a lot of sloppiness out of the above
analysis, but I would be surprised if the dynamic range is more than
12 stops. A similar analysis at ISO 1600 yields about 10 stops DR.
Thus it would appear that the D3's dynamic range is about the same as
Canon 1 series DSLR's.
Unfortunately the sample images are not appropriate for determining
the quantum efficiency of the sensor, which to my thinking is one of
the determining factors in high ISO performance.
The raw was shot in 12bit mode rather than 14-bit mode (all raw levels
were multiples of four in 14-bit units). It will be interesting to see
whether an image shot in 14-bit mode has more dynamic range, since the
12-bit sample here has a quantization step which just about equals the
noise. Theoretically that could get you a very tiny fraction of a stop
more, but I don't think quantization error is the limiting factor
here. Anyway, DR appears to roughly equal the Canon Mark 3 at ISO 200.
BTW, pattern noise (banding) seems fairly well controlled (though
visible in the deepest shadows if you boost them enough).
>> Stay informed about: Nikon D3 and D300 NEF raw files now supported by Dave Coff.. 
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