Originally posted by jatrax By this you mean this resolution would achieve the maximum quality for that particular size sensor?
Not exactly. I mean that going
beyond the particular MP numbers may always be
more economically done by going to a larger sensor.
It is a soft argument though because the respective resolution numbers may only apply to image centers and perfect AF. So, upgrading to larger sensors may make sense well below these limits. Moreover, the numbers are projections into the future and are entirely based on my gut feeling, not a scientific argument.
Originally posted by Cannikin intuitive sense to a lot of people. Perhaps an analogy will help
I tried to make things intuitive though.
You have several blur spot sizes and I believe it is a very intuitive concept to grasp that it doesn't make sense to look at / minimize one of the sizes without taking care of the others too.
Like with your car analogy, if you upgrade to 2000hp cars you have to consider speed limits.
Originally posted by VoiceOfReason Basically, would shooting with a 16mp sensor at f/9 vs a 24mp at f/9 where one is below and one is above the diffraction limit.
I hoped you could answer such questions yourself now. So, I failed.
BTW, F/9 isn't above the diffraction limit for 24MP. The Raleigh limit for 24MP APSC is F/11. But diffraction is always visible, below and above the Raleigh limit. Maybe, read my long post again.
Originally posted by Cynog Ap Brychan For reasons that escape me, I had always thought that diffraction was a factor of the actual diameter of the aperture hole, not its f number per-se.
You are correct and wrong at the same time. It depends on the factors you consider to be constants.
Case 1: Field of View is a constant, sensor size is a variable. Then diffraction effects (e.g., as expressed by LW/PH Raleigh resolution) are a function of the actual diameter of the aperture hole in mm. This is part of the equivalent camera theoreme which covers other effects like noise and depth of field too. I guess, this is where your idea is coming from.
Case 2: Field of View is a variable, sensor size is a constant. This is a more typical case corresponding to a change of lens with a given body. Then diffraction effects are a function of the F-Stop, i.e., the actual diameter of the aperture hole divided by focal length.
Case 1 and case 2 are not in conflict of course. Just rewriting the same formulas.