The Sigma DP3M has a foveon sensor instead of a regular sensor with bayer filter array. It's based on different wavelengths of light penetrating silicon to diff

The Sigma DP3M has a foveon sensor instead of a regular sensor with bayer filter array. It's based on different wavelengths of light penetrating silicon to different depths, which means that all 3 colours are stacked on top of each other, so you don't have to throw away 3/4 of your photons just because they happen to be a different colour than the dot they fall on. At low ISO the image quality is amazing, at high ISO it's very noisy. Also, the red channel is much noisier than the blue one. http://upload.wikimedia.org/wikipedia/commons/a/ab/Absorption-X3.png http://upload.wikimedia.org/wikipedia/commons/a/ab/Absorptio...