entry-level DSLR A 'digital camera' (also 'digicam' or 'camera' for short) is
a camera that takes video or still photographs, or both, digitally by recording
images via an electronic image sensor.
95. Many compact digital still cameras can record sound and moving video as
well as still photographs. In the Western market, digital cameras outsell
their 35 mm film counterparts. Digital cameras can do things film cameras cannot: displaying images on a screen
immediately after they are recorded, storing thousands of images on a single
small memory device, recording video with sound, and deleting images to free
storage space. Some can crop pictures and perform other elementary image
editing. Fundamentally they operate in the same manner as film cameras,
typically using a lens with a variable diaphragm to focus light onto an image
pickup device. The combination of the diaphragm and a shutter mechanism is used
to admit the correct amount of light to the imager, just as with film; the only
difference is that the image pickup device is electronic rather than chemical. Digital cameras are incorporated into many devices ranging from PDAs and mobile
phones (called camera phones) to vehicles. The Hubble Space Telescope and other
astronomical devices are essentially specialised digital cameras.
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