Originally posted by nomadkng Why would it be some gimmick?
I was ready an article where the theoretical MP limit of an APS-C sensor is somewhere in excess of 200 MP
This would be somewhat gimmicky because of the details drowning in diffraction blur. That blur is, because light spreads out from small apertures like wobbly waves rather than straight photons (apologies for this over-symplified explanation
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For our APSC-DSLRs, this diffraction blur starts smearing details, proportional to apertures becoming smaller than say F/8. The higher the pixel density, the smaler the pixel sensor sites, and the earlier the diffraction blur eradicates the resolution gain. With a 200 MP sensor, the sensor sites would be 3-4 times smaller (per each dimension), so diffraction blur would kick in from F2.8 or so.
That's the reason why people still spend good money for FF and medium format, where the sensor sites' size don't have to fall below a certain threshold for allowing a high resolution.
That's also the explanation, why small P&S cams with their small high-density sensors often don't have an aperture mechanism at all, but a grey ND filter(s) mechanism instead.
Last edited by Frater; 07-30-2013 at 12:53 AM.