Interesting topic.
I wonder if these studies of flat patches of noise patterns have gone further in explaining how they affect perception of detail and if it's measureable.
What they relate most directly to is bokeh, in real images, as there is no detail at those frequencies, generally speaking. With real detail, I doubt that any equation can be made that would objectively quantify subjective noise. I have done comparisons of noise vs resolution for detail, and when the trade-off is exact (4x the noise amplitude at the pixel level, same pixel frequencies for 4x the pixels) the higher-res pixels, noisier at the pixels level, give a better view of detail, IMO.
Here's an example:
The upper left is original 100% crop of Canon 20D RAW of a section of a Mockingbird's face, accidently under-exposed by about 3.5 stops at ISO 800 (effectively ISO 8200). In english-reading order, the other three are the RAW image binned down to 2x2, 4x4, and 8x8, which should reduce noise at the pixel level to 0.5x, 0.25x, and 0.125x of the original. The noise doesn't even look much better at 2x2, probably because of CFA pattern, but the pattern shouldn't be an issue at 4x4, and the noise, atlthough statistically lower, is still quite visible because of its low frequency. No matter how far you stand from the monitor, the original still looks the most detailed, and the noise in it isn't even an issue, compared to the others. The image is very RAW, so that conversion factors don't have much of an influence. IOW, no noise reduction at all, other than that caused by the binning, is applied. None of the normal chromatic noise reduction in a standard conversion is applied. I tried to keep factors to a minimum.
I think this whole "bigger pixels are better" stuff is a lot of nonsense. It is just a coincidence of current marketing and design pricepointing that results in some high-pixel count cameras with greater *image* noise. The noise need only increase significantly at the *pixel* level, and that is not directly relevant to the image (or the subject), unless you take the
number of them into account.
Can this kind of noise be seen in poster size prints of high end DSLR images?
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Digital noise has more patterning to it, so it is more distracting at the same strength and average frequency than grain, IMO.