EORI wrote in post #13876045
Let me try to understand your explanation. Are you saying that the effect of diffraction is outweighed by other factors and techniques that mitigate any reduction in sharpness from the effects of diffraction, at least at the current range of pixel counts?
It's not outweighed by anything. It's just that, at most commonly-used apertures, the pixel density is not sufficient for diffraction effects to be apparent.
For instance, with a 36MP full-frame sensor, the diameter of the Airy disc doesn't exceed the size of a single Bayer array until the aperture is f/16 or smaller.
And, even if you have a hypothetical sensor that is diffraction-limited at f/4, there is still good reason to increase the megapixel count further - by quadrupling (or more) the megapixel count beyond this point, you can then remove the AA filter without fear of moire, giving improved sharpness.
All things being equal, isn't it still true that as pixel counts climb, that diffraction will occur sooner (i.e., at lower apertures)?
Yes. Except that current full-frame DSLR sensors are nowhere near dense enough for this to be significant, unless you routinely shoot at f/18-f/22.