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View Full Version : When do Megapixels out resolve lenses?



wideangle
02-10-2011, 9:26pm
I have a question in regards to the wonderful world of camera megapixels and lenses. Is there are point at which a camera with a large megapixel count is going to out-resolve a lens? What I mean is, if you shoot for example with a lens on a 10 megapixel camera body and then put the same lens on an 18+ megapixel camera, I assume it's going to show up any "weaknesses" in the lens as a result of higher resolution?

Kym
02-10-2011, 9:29pm
At the limit of diffraction http://www.cambridgeincolour.com/tutorials/diffraction-photography.htm
Its the other way around, more MP (actually pixel density) means less usable (well that's a bit over the top, I really mean very sharp) image at a given aperture

wideangle
02-10-2011, 9:34pm
Interesting, it means that there is a limit in practical terms to how MP are in a camera before loss of IQ. IE - Smaller MP in a camera are going to be "tighter" hence appear sharper, then a camera with larger MP?

Kym
02-10-2011, 9:38pm
Interesting, it means that there is a limit in practical terms to how MP are in a camera before loss of IQ.

Very much so! It's why a 10MP sensor will have a sharper image at smaller apertures (eg f/16 f/22) than a 18MP (assume same size sensor)

In the link I gave above you can put your camera settings into a calculator that will tell you where the LoD cuts in (i.e. the airy disk is bigger than the pixel)

wideangle
02-10-2011, 9:42pm
Very much so! It's why a 10MP sensor will have a sharper image at smaller apertures (eg f/16 f/22) than a 18MP (assume same size sensor)

In the link I gave above you can put your camera settings into a calculator that will tell you where the LoD cuts in (i.e. the airy disk is bigger than the pixel)

Very interesting Kym, so it means that in reality the larger the megapixel camera count that smaller apertures are not necessarily going to be as good as on a camera with smaller megapixel count. This is very interesting as I wonder with cameras going higher and higher with megapixel count as to what effect this is going to have on IQ.