Video Cameras and Camcorders

Initially developed by the television industry, a videorequires various adjustments such as aperture
camera is used for acquiring electronic motionsettings to control depth of field and distance, zoom
pictures. The earliest video cameras were used byto control focal length and shutter speed to regulate
BBC for experimental broadcasts in 1930s. Theseexposure. It also requires adjustments in gain, which
were of John Logie Baird, the inventor of world's firstin electronics signifies amplifying signal strength.
working television system, and used theImager:
electromechanical disk for recording moving pictures.Modern cameras use CCD or CMOS as an imager.
By 1940s these were replaced by all-electronic videoThe lens projects an image on the surface of the
cameras that were based on cathode ray tube.imager, which exposes the photosensitive
These remained current till the 1980s when theyarrangement to light, which is converted to an
were replaced by cameras based on solid stateelectric charge. The imager converts the accumulated
image sensors such as a charge-coupled devicecharge into continuous analogue voltage and sends
(CCD), and later by Complementarythem to its output terminals. After a scan-out is
metal-oxide-semiconductor active pixel sensors.complete, the photo-sites on the imager surface are
Video cameras were primarily used for two purposes.reset and ready to receive the next video frame.
The first: the camera feeds real time moving imagesRecorder:
directly on a television screen for immediate viewing.This last section is responsible for recording and
The second: for recording for later viewing orwrites the video signal onto a recording medium: a
archiving. The videotape was the primary format inmagnetic videotape, optical disk media or hard disk.
which moving images were stored, which is nowHigh definition or HD refers to a video system that
being replaced by optical disc media, hard disk anduses higher resolution than standard definition (SD).
flash memory.Some of the latest models serve a dual purpose of
Modern video cameras neither resemble the earlycapturing still as well HD video. Nikon and Canon were
television cameras nor are they limited only tothe first to launch single lens reflex digital cameras
television use. Apart from professional use inthat include video capturing and recording.
television and some times film production, videoRecently HD capture has become a common feature
cameras are also used in security, surveillance andin sophisticated video cameras including those meant
monitoring through close circuit TV cameras.for home use. Canon HG10 AVCHD Hard Disk Drive is
Recently, Camcorder, a portable consumer devicecompact in size and has 40 GB hard drive and gives
has fast emerged as one of the most popular uses1920x 1080 resolution crystal clear images. Panasonic
of technology related to video cameras.HDC-DX1 DVD includes nearly all features that
The three major components of video camerasanyone would like to see in a DVD camcorder. One
include: the lens, imager and recorder.of Sony's top models is Sony HDR-CX7 AVCHD that
Lens:contains Carl Zeiss Vario-Sonnar optics and Super
The first component in the light path is the lens. ItSteadyShot optical image stabilization.