Yepp, you mixed some things. The first FoveOns were 5Mpixel on three Layers, which (could) be summed up to 15MPixel. The next generation was the Merrill, where about 15MPixel on 3 Layers can be counted to 45MPixel. The new Quatto Design ist again 3layered, but just the blue one get's 19MPixel, where the other 2 are just about 5 MPixel each. Now happy counting
At the End, the results are crucial.
It may have 45 million photodiodes, but that is not the same as megapixels, and I really wish Sigma would stop being so misleading.
This is of course confusing, but it's not a lie, because... let's define a pixel. You refer to it as a Pixel is the Picture which comes out from the cam. The Pixels from the Sensor are something different... you could also count each layer as a single Pixel, because it has an own wired output and the information is capsulated within this *single* Lighttrap. Remember the Nikon D2X (or was it the D1x?), there the Pixels were halfsized, so what do you count?
It's some kind of definition. The Sigmapeople have the same "problem" as Intel had 10 years ago... recognizing that Megahertz has nothing to do with speed, but the people don't know this. So you have to catch them with Numbers they understand.
Furthermore, the D800 and 645D both have more information to start with. They are resolving details that are not even present in the SD1 image at all, despite it's sharpness
No, they DON'T, that's what the image should have told you. I could resize the Sigma-Picture 4 Times and have more resolution, but not more information.
A light sharpening filter can deal with the softness in a few seconds, and then the SD1 is at a real disadvantage.
Please try and proove me wrong, the RAW-Data is available for download @dpreview.com
By the way, the Size of the photodiodes are of course really important, especially on lowlight, but the technology solves some of the problems. On the paper no one could beat my old 5D with ca. 8.2 Microns, but in reality your 1DX would run circles around it