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Digital camera has lens and shutter like a regular camera. Light enters into the camera but does not fall on a photosensitive film. Instead of films the light strikes an array of image sensors or photosensitive cells instead of film. The sensor array is a chip about 6-11 mm across. Each image sensor is a charged-couple device (CCD) which converts light into an electrical charge. The charge is stored as analogue information then digitized by another bit of technology called an analogue to digital converter (ADC).
Every receptor in the array of thousands creates one pixel, and for each pixel a certain amount of information is stored. Some digital cameras use CMOS chips as image sensors. Standing for complementary metal oxide semiconductor, CMOS refers to the process by which the sensor is made. The process is the same one used to mass produce DRAM and microprocessors so CMOS sensors are significantly cheaper and easier to make than CCDs. CMOS sensors consume less power and can have other circuits included on the same chip these are its other advantages.
These additional on-chip features can include analogue-to-digital conversion, cameral controls, image compression and anti-jitter stabilization. However, these other circuits use space that would normally be used for light sensing. This makes the sensor array less sensitive to light, resulting in lower image quality when shooting indoors or other low light conditions. In the final tally, CMOS cameras are smaller, lighter, and cheaper and more energy efficient but is prepared to sacrifice some image quality.
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