5dmk2 and d800 same exposure time, f-stop base iso
5dmk2 developed in camera raw and DPP and d800 in camera raw so that details/information can be seen equally in the white house wall and in the white towel in front of the garden house =high lights reproduction.
Then we look in the shadows, low levels , an area is selected in the low levels and auto contrast is laid, auto contrast are showing levels , details, noise in the selected area , no personal influence , photoshop is calculating the signal level from the pixels values. This is the results of 2-3 extra stops DR in low levels. And how to use it- it is up to the photographer and the skills to use photoshop
I have lent the raw files to a number of talented members at dpreview , they have all checked and verified the results by them selves.
Great comparison of noise at 100% scale vs. 66.7%!