« on: January 21, 2013, 03:41:10 PM »
If we're talking about two cameras, both with 18MP of digital perfection, then presuming each has a lens up to the demands of the sensor, there will be no difference.
Not even close.
Camera A has a square sensor, 1" x 1". Camera B has a square sensor, 2" x 2". Both cameras have a 1024-by-1024 pixel array, for a grand total of one megapickle. Both sensors are digital nirvana, counting photons at the very limit of what quantum mechanics allows.
Each of camera B's pixels can gather four times as many photons as camera A's pixels. Camera B has two stops more dynamic range and the gradients it captures are two stops smoother, with two stops less pixelation. Make a 2" x 2" print from both, and the one from camera B will show two stops more detail and appear that much sharper.
Sure, but you are not always dynamic range limited, for instance in a studio or in a foggy landscape situation. The only difference will be that camera B's sensor needs four times less exposure (and even that doesn't matter when using lighting or a tripod).