I listed my entire procedure in detail! I wasted like ten minutes typing it out. It's the same thing DxO does.
Really? It doesn't sound like you did this:Quote from: DxO LabsWe perform noise measurement using a transmission target placed on top of a uniform light box. The transmission target, designed by DxO Labs, is made of a plate of thick black plastic with precision-drilled holes which are equipped with a range of neutral density filters designed to absorb the light identically for all wavelengths.
The filters are made of pure optical glass with no structures that can be measured as noise. (While other image quality measurement solutions make use of printed targets, we believe such targets are inappropriate for noise measurement testing, as the intrinsic noise pattern of the print paper may be recorded by the tested camera and then confused with the camera’s own noise pattern.)
We place high-density filters on neighboring positions to limit reciprocal illumination of the patches.
The light box (placed behind the target) is composed of two fluorescent daylight spectrum tubes with a diffusing sheet on top, achieving a perfect uniformity on each filter. The luminance is about 1500cd/m2.
We use filters having different light absorption levels ranging from 0% to 99.99% in order to test across a dynamic range of 4 density steps (= 13.3 f-stops — a dynamic range much greater than today’s digital cameras). When shooting such a chart, the sensor of the camera being tested sees a wide range of light levels, with a 1/10,000 ratio from minimum to maximum. For comparison, a printed target dynamic is typically 2 density steps (6.65 f-stops), which is inadequate to simulate high dynamic range or back-lit scenes.
Each uniform zone on the chart (a “patch”) is measured for luminance (cd/m2) with a certified luminance-meter; then all the values are input into DxO Analyzer software.
Once we measure the target and calibrate the DxO Analyzer software, the selected camera shoots an image of the noise target at different ISO settings, and we measure the noise for each color channel of the target image (R, Gr, Gb, B). We compute the mean gray level and noise values for each patch and for all images shot at different ISO settings. We then interpolate these numerical values for all gray levels to calculate and plot signal-to-noise ratio (SNR) curves, from which DxO Analyzer extracts the SNR 18%, the dynamic range, and the tonal range.
Perhaps the 10 minutes you spent typing out your 'procedure' wasn't the only time you've wasted on this 'analysis'...
As I said I was not measuring SNR, not measuring integrated tonal response, not measuring color fidelity, not measuring for actual ISO ratings, etc. They are measuring tons more stuff, lots of more complicated stuff. I was just measuring maximum DR at base ISO which is vastly simpler than doing all of that other stuff. It is possible that their software extracts the dark current patch SNR ration and the blown channel and does actually what I and others have done. And I mean I did end up with the exact same ISO 100 results for the 5D2 DR.
I just hope that the main sensor area turns out to not act like the masked area this time. That would be awesome. I'd love to be wrong. But also note that all of the talk from Canon about the 5D3 has carefully left out low iso, they always mention improved for mid and high iso.
And while this next post below is a bit speculative, his info is a bit down the line and speculative but how about this quote from someone not from Canon but with ties to them (I don't know who he is but he has been right about everything Canon the last few years on larger scale issues, he certainly might not have all the itty bitty tech stuff correct, etc.), quoting his post on another forum:
"I told you so, the 5DmkIII sensor is mainly a "polished" version of the former mkII sensor. Not that this is not a real improvement, but the step forward in real image quality is in fact marginal if you shoot RAW mainly. The 1Dx however has a sensor with a complete redesign. Expect it to have some real native characteristics that are above the 5DmkIII. .... The 1Dx performs some better in almost every department..... ISO, DR.... except for a few mp. Still the 5DmkIII..... is mature enough to completely satisfy the needs of enthusiast amateurs, semi pro's and professionals who prefer the compact body size over the 1Dx's additional qualities."
Off case take that with a grain of salt, but it sounds like, as some on DPR speculated, that maybe (again this is very much speculation now and may be prove to be entirely wrong) they may have decided to use the old fab for the 5D3 to save money again and only used the new fab for the 1DX sensor.
And I think he may be playing down the high iso improvements of the 5D3 a little bit. And maybe the 1DX sensor won't even be that different and it was just marketing spiel.
Anyway this guy has hardly been a Canon basher, in fact, he had long been a very 100% rah-rah cheerleader on everything they ever did.