#17. "RE: D800 High ISO performance - specific performance ranges" In response to In response to 0
Maybe some details on DxO's measurements would help. Camera performance is highly dependent on what ISO levels you use in practice.
As DxO measured the low light ISO, they calculated the D3s at .4 stops better than the D3 and .6 stops better than the D3x. The D3 at introduction was .15 stops better than the D3x. But at high ISO levels, I interpret the advantage of the D3s to be greater - nearly a full stop.
For context, the other overall scores for color and dynamic range were the same for the D3 and D3s - slightly below the D3x. But that's not the full story as the D3x advantage comes from low ISO performance where it is substantially better. At higher ISO levels the color and dynamic range scores favor the D3/D3s.
The detailed measurements for the D3s show improved performance over the D3 at almost every ISO level - with the difference in performance greatest at high ISO levels (above ISO 1600). The D3x excels at low ISO levels with far superior performance at lowest or base ISO - minimal noise and exceptional color and dynamic range. At ISO 200 and beyond there is little difference until you get to ISO 1600 and above where the D3s shines.
What this means is there are optimum ranges where each camera has an advantage. The high megapixel cameras perform better than anything on the market at base ISO - ISO 50 to ISO 200. With all these cameras there is an increase in noise and a dropoff in color and dynamic range as ISO increases - and they are pretty similar from ISO 400 to ISO 1600.
The D3 initially had small advantages over the D3x at higher ISO levels, but with the D3s the camera apparently was re-tuned to achieve significant improvements at high ISO levels.
What this means for the D800 is that you can expect fantastic color and dynamic range at base ISO. But as you move into normal and high ISO levels the larger pixel pitch of the D4 will prevail. As for comparison with the D3/D3s/D700 - it appears the only place the latter might outperform the D800 is at high ISO levels - above ISO 1600 or even ISO 3200.
Using the D7000 as a reference point for the pixel and processor performance in the D800, we should see a significant step of improvement (I'd estimate a full stop at all levels). The D7000 reduced the pixel pitch from the D3x, but was able to generate substantial improvements in dynamic range, color, and high ISO performance to nearly match the D3x in those areas. That means really good things for the D800.