With all the comparisons of high ISO raw files that's been going on lately, my pea brain needs some clarification on a few issues. My understanding has always been that raw files represent the information that the camera actually captures in its purest form, with no manipulation whatsoever. However, others have mentioned that Nikon bodies "cook" their files by applying in-camera noise reduction. Obviously, at that point a raw file doesn't represent what the camera captured in it's purest form, and therefore does not accurately represent the performance of the sensor. Does Canon do the same thing with its raw files?
This raises a few more issues. If a camera applies noise reduction to its raw files, what's to say that it can't extend dynamic range with in-camera processing as well? I defer whether or not extending DR of raw files via in-camera software is even possible to the real tech heads on here, but if a camera did do this, how would you even know unless a manufacturer disclosed this info in its literature?
On one hand, I can see why you'd want a true, unprocessed raw file as a means of measuring sensor performance. On the other hand, if in-camera processing is sophisticated enough to improved overall IQ to the point where that a photographer can't even tell that in-camera processing was applied in the first place, who really cares?