d_chiesa wrote:
I understand the \'per surface area\' noise argument. But what about dynamic range? That should be reduced at the \'per pixel\' level with smaller pixels, and not made up by having more of them...
I don\'t care much about noise, but better DR would be nice.
Unfortunately, from the standpoint of RAW data... noise & dynamic range are one and the same. DR is the range from the brighest detail you can resolve, to the darkest detail you can resolve. However, noise will disrupt the darkest details you can resolve --- effectively reducing DR. Hence, more noise = less DR.
I\'m not a scientist. But I play one on TV. So here\'s my unscientific opinion:
If the technology level is equal, then the noise generated by electronics in a camera would be the same for a 24 MP sensor and a 6 MP sensor. The big photosites on that 6 MP sensor will have a much stronger signal, just because it has a large surface area to receive lots of photons. But on that 24 MP sensor, the individual pixels are 4x smaller, therefore its signal is 4x weaker, and will need to have a gain applied that\'s 4x stronger. Even though the noise generated by electronics in the 24 MP and 6 MP sensors are the same, the output read noise in that 24 MP sensor will be 4x bigger --- simply because a gain 4x stronger would\'ve been inadvertently applied to it.
d_chiesa wrote:
I understand the \'per surface area\' noise argument. But what about dynamic range? That should be reduced at the \'per pixel\' level with smaller pixels, and not made up by having more of them...
I don\'t care much about noise, but better DR would be nice.
Unfortunately, from the standpoint of RAW data... noise & dynamic range are one and the same. DR is the range from the brighest detail you can resolve, to the darkest detail you can resolve. However, noise will disrupt the darkest details you can resolve --- effectively reducing DR. Hence, more noise = less DR.
I\'m not a scientist. But I play one on TV. So here\'s my opinion:
If the technology level is equal, then the noise generated by electronics in a camera would be the same for a 24 MP sensor and a 6 MP sensor. The big photosites on that 6 MP sensor will have a much stronger signal, just because it has a large surface area to receive lots of photons. But on that 24 MP sensor, the pixels are 4x smaller, therefore its signal is 4x weaker, and will need to have a gain applied that\'s 4x stronger. Even though the noise generated by electronics in the 24 MP and 6 MP sensors are the same, the output read noise in the 24 MP sensor will be 4x bigger simply because a gain 4x bigger would\'ve been inadvertently applied to it.
