bugnuts writes "Nearly all modern DSLRs use a Bayer filter to determine colors, which filters red, two greens, and a blue for each block of 4 pixels. As a result of the filtering, the pixels don't receive all the light and the pixel values must be multiplied by predetermined values (which also multiplies the noise) to normalize the differences. Panasonic developed a novel method of "filtering" which splits the light so the photons are not absorbed, but redirected to the appropriate pixel. As a result, about twice the light reaches the sensor and almost no light is lost. Instead of RGGB, each block of 4 pixels receives Cyan, White + Red, White + Blue, and Yellow, and the RGB values can be interpolated."
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