Optical vs Digital Zoom

Tip: Try not to use the digital zoom function.

Cheaper camera models come only with digital zoom, whilst the high-end ones come with both optical and digital zooms. Optical zooms work basically like your conventional zoom lens whereby lens elements in various groups are moved to change the focal length of the lens. Digital zooms are only present in digital cameras, and basically work by utilizing only a smaller portion of the CCD element. (The CCD, or charge-coupled device, records picture information.) This reduces the angle of view and hence gives the impression that you are closing in on a subject far away. Image quality obviously suffers when a smaller area of the CCD is used to represent the same image size. There is a noticeable increase in "noise" in the final image, which can be compared to graininess in conventional film. Hence, image quality is high for optical zooms and rather poor for digital zooms.