So what I said in a previous post about same sized but different Mp Number sensors having different CoC seems to be indeed true. This fact is not reflected in any DoF calculator that I know of.
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Hmm, sounds like there is still some confusion .... let me try again.
The CoC on the sensor is determined by the optics, not the sensor. Two different sensors, with different pixel pitch (same physical size but different pixel count), will have the same CoC, expressed in physical units like microns, if the same optics are used to form the image. This is intuitive for film cameras (film granularity has nothing to do with CoC) and the same principle applies for digital cameras (pixel density has nothing to do with CoC).
Of course if you measure the CoC in pixels instead of microns, then pixel pitch enters the equation. But this is a backwards way of thinking, sort of like a film photographer thinking "my film has a grain size of 8 microns and my image occupies 2400 grains of film" rather than "my image occupies 19mm of film". When calculating CoC, the second way of thinking seems simpler, and it emphasizes that pixel pitch or film grain is irrelevant.
DoF calculators require the user to enter phisical quantities like image size. Given just the pixel count of a digital file (like 6MB = 2000x3000 pixels) and no information on physical image size or pixel pitch, there is not enough information for the calculation. The DoF calculator can calculate how large a CoC is formed by a particular lens, but has no way of translating this into pixels without knowing the phisical pixel size or sensor size.