The general consensus I've always heard is that noise may be a bit more noticeable at 100% in the D800, but its greater resolution effectively cancels any slight advantage at 100% a 5D III file may have, so it turns out either to be a wash or, more likely, cleaner overall at high ISO in the D800. These tests confirm that consensus. Who ways that the 5D3 is cleaner? It is a minority view in conversations I've had, and wrong, too. I suppose it does have more aggressive jpeg noise reduction, but this is a bad thing, and the 5D3 is known for its mushy, undetailed jpegs. DXO Optics is good for getting every last drop of detail from a 5D3 raw file, and sometimes they give results that can be printed to about 19 x 11" and look quite detailed. You can get away with 16* by 24* and have the same detail in a D800 file, though. Of course, the significant advantage in read noise means that it's much easier to get clean shadows at base ISO after positive exposure compensation from the D800. Canon needs to work on read noise if it hopes to ever catch up with Nikon in image quality. That said, both are nice cameras. I have the 5D3 and enjoy it but a good friend has the D800 - I shoot with it once in a while and I love those D800 files.