Everybody talks like Sony/Nikon have some sort of amazing technological advantage over Canon. Except for DXOMark scores there is nothing that shows this. Dispite what DXOMark says tests at DPReview show that the 5D Mk III has more dynamic range than the D800 http://www.dpreview.com/reviews/nikon-d800-d800e/19
So either Nikon has some really crappy processors that mess up the 2.7 stop advantage that DXOMark says the D800 has, or we should stop quoting, worrying about, or looking at what DXOMark says.
Or dpreview is using JPEGs and not RAW data.
While you're on that dpreview page, make these changes:
Set the "Canon EOS 5D Mark III" to "HTP On"
Set the "Nikon D800" to "ADL Extra High"
This should give you:
Canon EOS 5D Mark II - ~33 to ~2
Nikon D800 - ~38 to ~2
The whole point about DXOMark is that they are supposed to be measuring the sensor without all the electronic nannies.
So, yes ADL and HTP can stretch the data to expand the dynamic range, but, DXOMarks claim that the D800s sensor alone has more dynamic range just doesn't hold water.
Or just look at DXOMarks own data the Canon 5D Mk III matches or outscores the Nikon D800 on the screen scores for ISO Sensitivity, SNR 18%, Tonal Range, and Color Sensitivity, yet for some reason the Nikon D800 has a massive Dynamic Range advantage? My understanding that all of those other scores are necessary components that would give the camera its dynamic range. It just doesn't add up!
The Canon 50D was the first casualty of DXOMark. It had much better sensor performance than the D90, yet, people kept pointing to DXOMark and saying how lacking the camera was. Well, sorry the vast majority of people who actually have owned a 50D know it was one heck of a camera, much better than it was ever given credit for.
So, stop getting a complex over Canon's sensors because of DXOMark, and focus on how they actually perform.