Baskadia

Digital camera

FOR MORE THAN 200 YEARS, CAMERAS recorded pictures as chemical changes in silver-containing substances, on a strip of flexible, celluloid film. The digital camera records pictures in electronic form. At its heart is a specialized integrated circuit known as a charge-coupled device (CCD). This has millions of micro-units known as pixels. It works in the opposite way to a miniature computer or TV screen.

Instead of electric signals making pixels shine, when light hits a pixel it generates a tiny electrical signal, according to the light's colour and brightness. The signals from the CCD's millions of pixels are analogue: they vary continuously in a wave-like fashion.. They are converted by a microchip to digital codes of numbers, represented as on-off electronic pulses. The digital signals are processed and fed to the camera's internal memory or a removable memory device such as a data card or memory stick.

Photographs can be downloaded from a digital camera to a computer via a cable or in some cases a wireless link. Some digital cameras automatically reduce blurring caused by camera shake or fast movement, some can record video clips as well as still pictures.