A sensor is made up of millions of photodiodes, often called photosites or, confusingly, pixels. Each photodiode records the amount of light that is hitting that particular point, which results in an image map of where the light hits the sensor. Where no light reaches the sensor at all, the photodiode will record no information, resulting in a black pixel in the recorded image. Where the amount of light hitting the sensor exceeds what the photodiode can hold, a white pixel will be recorded. Between these two extremes is a range of grey pixels.
Above each photodiode is a microscopic coloured filter, usually of red, green or blue. As we know, there are various different colour patterns for these filters, known as colour filter arrays (CFAs), but the most commonly…
