green digital cameras

The number of photosites in the image sensor gives the digital camera its megapixel ( millions of pixels ) rating. Each photosite corresponds to a pixel in the final image, so a camera which is rated at six megapixels, for example, has an image sensor which is 3008 pixels wide by 2000 pixels high.

When light hits the image sensor it is converted into electrical signals which are built - up and fed to an analog - to - digital ( A / D ) converter. The A / D converter changes the electrical signal into binary numbers which are processed by a computer housed in the camera body. Once the numbers have been harvested the resulting image is stored on a memory card.

Photosites can only measure intensity of light - - not color. In order to produce a colour image, each photosite must be covered with a colored filter which can be red, blue, or green. These are the three primary colors which can be combined to produce any other colour including white.