Originally posted by Alan 2 I have to admit most of this is over my head so I skimmed it and skipped down to the conclusion. His conclusion is that we're hitting the wall with lens resolution and MP.
4/3 system 10MP
APS-C 15MP
full frame 35MP
Anything more than that and it's just bigger files with no real increase in resolution. If what he says is true then the K20D is about all you can get with APS-C.
The article merely talks about the diffraction limits of a lens over the physical size of a pixel (the pixel pitch).
However, if we don't stop down the lenses too much, we maybe able to get more resolution as far as diffraction effect is minimized.
That's why if you attach a lens like the DA 16-45 and use the MTF program, the camera set at f/4 to f/5.6 at the wide side in order to maximum the resolution. I think Pentax know well about this diffraction effect (so that they avoid to stop down the wide lens in the MTF program mode, as far as possible).
Having said that, to make a lens has the highest possible resolution at fast aperture yet again is another thing that is rather difficult, anyway.