![]() ![]() The GH5S will not be cost-effective for stills, probably >2.5X the cost of FF bodies that produce superior stills (e.g., the cheaper and smaller Sony A7), but pricing of video cameras doesn't really follow sensor size. Those are excellent stills for a video-centric camera with MFT sensor. Nope noise is just a number, or average, and downsampling doesn't change that number. "Noise is not just one number - it has a spectrum, as well, for example." The appalling thing is your refusal to look at your own examples. You're averaging the whole image, that's why the process is basically instant. You're not merging levels, that takes processing, and time, a good deal of it. This make 5^2 = 25 possible combinations for the noise level, detailed as this :" Downsampling of 2x to merge 2 pixels into one. Probability of each level 1/5 for a truly random noise. "Let's say we have five noise levels (-2, -1, 0, +1, +2). I suggest you look at your own examples to verify my point. The downsampling does reduce the noise count, but also reduces the count of non-noise pixels.'" "'No, it doesn't, as an average of the total number of pixels. None, and it's easy to see this non-change. Just from your 3 image sample there is no average reduction in noise as you downsampled. There's no singling out of noise pixels in the downsampling, averaging, process you describe. Or do noise thinking correctly: 500 pixels with 2 percent noise downsampled into 100 pixels will still have the same 2 percent noise-so that's 10 pixels for the bigger sample and 2 for the small smaller. A downsampling of the image won't do anything to exclude just the blue pixels of intensity X. Say you want to remove randomly distributed blue pixels at intensity X from a sample, you'll have to write code to find those pixels. Random noise will still have the same average concentration in the image after downsampling that's how the math, and downsampling, work. "noise value decreases when the number of combined pixel increases, because the noise is random," I suggest you try the process, it doesn't work.Īlso your math makes MY POINT for me, since this point of yours is absolutely untrue: "Then I suggest you wipe off that dust on your computer screen. ![]()
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