The Analog to Digital Converter (A/D Converter) transfers the raw analog signal captured by the camera to a digital value. The digital value is sent to the computer in ADUs (Analog to Digital Units). The A/D Converter also determines the bit resolution of the analog to digital conversion. The more bit resolution the A/D Converter has, the greater the range of ADUs, which yields a better range of image contrast from the camera. (If "X" equals the bit resolution of the A/D Converter, then 2expX = total range of ADUs.) For example, many commercial digital cameras use a 12-bit A/D Converter which has 4,096 ADUs, and high-end astronomical CCD cameras typically use a 16-bit A/D Converter which has 65,536 ADUs.