I read following statements in Eyes vs Numbers:
I think though that the main problem is that DxO is analyzing raw camera data, which does not include any correction of fixed pattern noise. DSLR cameras remove these noise sources before storing their raw data. Medium format cameras do not. DSLRs also apply a lot of noise reduction algorithms before storing the data...Nikon, for example, does a lot of on-chip noise reduction to their D3 and D3x raw files
I feel following needs to be said, for Michael's statements may be taken by some readers too literally; this is not for or against any camera but for the better understanding of these issues.
1. All Nikon DSLR cameras cut off a portion of the pixel data, thereby removing pattern noise (one could not name this "noise reduction" without provocing the international Nikon community to violent responses). All Canon DSLRs keep the raw data "uncut". This difference may have caused the ridiculous assertion by DxO, that the D3X has two stops greater dynamic range than the 5D2.
2. Noise reduction in the sense most people understand it will be performed on raw data only by Sonys, at least by the A700 and A900. This step could not be disabled with an earlier firmware version of the A700, but now OFF means OFF, apparently.
3. On-chip (on-sensor) noise reduction occurs with all CMOS sensors, which are inherently more noisy than CCD. However, that is single-pixel noise reduction, which has absolute nothing to do with the noise reduction in the sense as it is done in raw processing software or by the mentioned Sony cameras, namely based on the context of pixels.
4. The raw data of the Phase One cameras is far from being really raw.
Finally, there is nothing wrong in analyzing raw data and making certain conclusions based on that; at least I am doing just that without feeling guilty. In fact, one can make certain findings only
based on the raw data. However, one needs to be careful with those findings. I'm afraid, in the DxO evaluation of the P45+ they used ACR for the analysis; if so, that invalidates all of their findings.