But all that is just tuning, and demosaicing is only non-trivial if you want to "fake" a higher resolution -- otherwise just downsample. Same with denoising.
The main point is actually what you say in #3 -- that they are linear. That's what I mean by being accurate.
Compressing the dynamic range is an artistic choice that will not make an image look like what our eyes see. Film, for example, is more tolerant to overexposure because it has a nonlinear response -- but that's objectively incorrect. Our eyes already compress the dynamic range in a kind of ~logarithmic way. So you don't want to do that on image data, or it ends up being done twice! Which is precisely why bad HDR images can look so fake. Artistically you'll always have to deal with whether you want to compress dynamic range and how.
But my main point stands -- the data coming from CMOS is objectively accurate in a way that film is not. It's linear. It's not compressing range at the top or anything like that, or oversaturating certain colors, etc.
The main point is actually what you say in #3 -- that they are linear. That's what I mean by being accurate.
Compressing the dynamic range is an artistic choice that will not make an image look like what our eyes see. Film, for example, is more tolerant to overexposure because it has a nonlinear response -- but that's objectively incorrect. Our eyes already compress the dynamic range in a kind of ~logarithmic way. So you don't want to do that on image data, or it ends up being done twice! Which is precisely why bad HDR images can look so fake. Artistically you'll always have to deal with whether you want to compress dynamic range and how.
But my main point stands -- the data coming from CMOS is objectively accurate in a way that film is not. It's linear. It's not compressing range at the top or anything like that, or oversaturating certain colors, etc.