Where is your evidence or explanation?
For real, usable DR tests, look to IR and DPReview. (Unfortunately DPReview no longer posts RAW DR, but their tests are still valid for JPEG.)
The explanation has been posted repeatedly, and was posted again just a second ago.
I tested the DR myself and got same results and so have others.
You're making the same mistake as the others. Noise inflates the black point. Down sampling reduces noise, lowering the black point. But the black point is not actually the floor of dynamic range. The floor is the point where usable detail ceases to exist.
Down sampling actually throws away detail. It cannot extend DR.
I've seen improvements over that time period. DPReview saw improvements.
On what? 5D3 has actually worse DR than the 1Ds3.
In JPEG the 5D3 is better, as noted by DPReview. Unfortunately they did not post RAW values for the 5D3.
Imaging Resource has Imatest RAW values for both, and the 5D3 is one stop better.
real world, accounting for banding, I'd say D800 does more than 3 better than 5D3 and even ignoring banding it's more than 2.
"Real world"...that would be a switch. Please post real world shots that prove this. Include a transmission step wedge. Oh yes: downloadable RAW files for analysis are mandatory.
And not that I want to go here, but you've finally gotten me partially to this point, and sure even the most brilliant are wrong at times, absolutely true, and I'm not saying who here and on the other forums is who, but there are not only engineers but theoretical physics PhDs and other such, including some who are world renowned, posting in some of these threads and on some other threads and.... not on your side on this.
What is this: an appeal to imaginary authorities? http://www.nizkor.org/features/fallacies/
Whether or not the 5D4 has better DR has nothing to do with these stupid threads, and everything to do with their engineers. I have little doubt they are working on it.
Did you know that another division of Canon sent a patent for better DR to the DSLR division and got told to get lost, DR, what?, why? bye. Apparently they didn't even let their engineers look at it! So maybe they do need to be woken up.
A Canon employee (non-DSLR division) on another forum.
More imaginary friends = no source. Don't repeat the claim without a source.