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I believe that only applies to their 11-bit "RAW" encoding. That would be something akin to Canon's sRAW and mRAW, not necessarily in encoding, but in lossyness. Neither are actually RAW files, they encode data in a specific way. In Canon's case, the m/sRAW formats are YCb'Cr' formats, or Luminance + Chrominance Blue-Yellow + Chrominance Red-Green. The Y or Luminance channels is stored full resolution, however the Cb and Cr channels are stored "sparse". In Canon's case, all of the stored values are still 14-bit precision, but they do store lower chrominance data. Canon's images would be superior to Sony's, in both that they store more information in total, as well as with a greater bit depth...however both will suffer from the same limitation: The information is not actually RAW, which severely limits your editing latitude.
Generally speaking, the fact that these formats store lower resolution color information doesn't matter all that much. Because of the way our brains process information, if done carefully, a lower resolution chrominance is "missed" in favor of a higher level of detail. YCbCr formats have been around for a long time, since the dawn of color TV even. The Luminance channel was extracted and sent in full detail, while the blue/yellow and red/green channels were sent separately, in a more highly compressed format. This actually allowed color information to be piggybacked on the same signal that "black and white" TV channels were sent on, making it possible for B&W TVs to pick up the same signal as Color TVs.
If you have paid any attention to Canon's video features, you've already heard of similar video compression techniques. You may have heard of 4:1:1, 4:2:2, or 4:4:4. Those numbers refer to the Y, Cb, and Cr channel encoding. A 4:1:1 encoding has full luminance and 1/4 Cb & Cr channels. A 4:2:2 encoding has full luminance and 1/2 Cb and Cr channels. As you might expect, a 4:4:4 encoding use the same sampling rate for all three channels, and is effectively "full resolution". A standard RAW image is also technically a 4:4:4 R'G'B' image.
Jrista - did not appreciate that for mRaw/sRaw so thank you. My understanding on Sony is however, that their 11 bit RAW is their standard raw. I'm not sure if you read the whole article, but Tom is talking about deficiencies as a result, and he's comparing it to the D800. There's a further link embedded
which I believe confirms that they do the same on all their RAW encoding.
Don't get me wrong, I think many people would not notice it or can work around it - Fred Miranda has been positive in his review and he's a canon user - in fact I think there's a whole forum on his site discussing it in detail. To me it just seems somewhat self-defeating - you have a sensor with better DR than your competitors but you then impair the output with your compression scheme which "fails" when you have scene with higher DR.
Maybe I misinterpreted the information...