01-13-2011, 09:07 AM
[quote name='PuxaVida' timestamp='1294906868' post='5467']
If I understand you correctly, you mean down sizing pixels would provide so very small picture elements that we wouldn't be able to see the jagged edges (which are actually not there in the real image source), and we can easly get rid of the AA filters. If so, isn't it again a matter of magnification? I think this is only valid for very large prints, right?
[/quote]
Well you don't need an AA anti-aliasing filter if the sensor pixel size is way less than the lens's "circle of confusion". In other words, if the sensor pixels are small enough, every lens "looks blurry" to it anyway, even without an AA filter to provide artificial blurriness.
So if you have a lens that can resolve 50 million pixels, and you have a 200 million pixel sensor, then there is no need for an AA filter between the lens and the sensor, to get rid of weird, fine, false patterns in the result image.
The overall point theoretical point is that, if you had say 16 times more pixels in the sensor than you need in the result image, you could "downsample" the image by 4 times linearly, and end up with an image having 4 times less apparent noise. A fancy way of repeating what was said above, that as the pixels get smaller, if their per-pixel noisiness doesn't change, the final image to some extent could show less and less noise.
If I understand you correctly, you mean down sizing pixels would provide so very small picture elements that we wouldn't be able to see the jagged edges (which are actually not there in the real image source), and we can easly get rid of the AA filters. If so, isn't it again a matter of magnification? I think this is only valid for very large prints, right?
[/quote]
Well you don't need an AA anti-aliasing filter if the sensor pixel size is way less than the lens's "circle of confusion". In other words, if the sensor pixels are small enough, every lens "looks blurry" to it anyway, even without an AA filter to provide artificial blurriness.
So if you have a lens that can resolve 50 million pixels, and you have a 200 million pixel sensor, then there is no need for an AA filter between the lens and the sensor, to get rid of weird, fine, false patterns in the result image.
The overall point theoretical point is that, if you had say 16 times more pixels in the sensor than you need in the result image, you could "downsample" the image by 4 times linearly, and end up with an image having 4 times less apparent noise. A fancy way of repeating what was said above, that as the pixels get smaller, if their per-pixel noisiness doesn't change, the final image to some extent could show less and less noise.