A professional video camera (often called a "television
camera" even though the use has spread) is a high-end device for
recording electronic moving images (as opposed to a movie camera, that
records the images on film). Originally developed for use in television
studios, they are now commonly used for corporate and educational videos,
music videos, direct-to-video movies, etc. Less advanced video cameras
used by consumers are often referred to as camcorders.
There are two types of professional video cameras: High end portable,
recording cameras (which are, confusingly, called camcorders too) used
for ENG image acquisition, and studio cameras which lack the recording
capability of a camcorder, and are often fixed on studio pedestals.
Technology
Professional video cameras capture and transfer two dimensional images
sequentially, at specified capture rates, usually in the visible range
of the electromagnetic spectrum. These images can then be transmitted
to television receivers and replayed on a screen (CRT or LCD) at a frame
rate approximating that used by the camera. They serve as a means of communicating
valuable information across large distances: world events, telerobotic
exploration of planets or satellites, space stations, etc.
It is common for professional cameras to split the incoming light into
the three primary colors that humans are able to see, feeding each color
into a separate pickup tube (in older cameras) or charge-coupled device
(CCD). Some high-end consumer cameras also do this, producing a higher-quality
image than what is normally possible with just a single video pickup.
Studio cameras
Most studio cameras stand on the floor, usually with pneumatic or hydraulic
mechanisms to adjust the height, and are usually on wheels. Any video
camera when used along with other video cameras in a studio setup is controlled
by a device known as CCU (camera control unit), to which they are connected
via a Triax or Multicore cable. The camera control unit along with other
equipments is installed in the production control room often known as
Gallery of the television studio. When used outside a studio, they are
often on tracks. Initial models used analog technology, but digital models
are becoming more common. Some studio cameras are light and small enough
to be taken off the pedestal and used on a cameraman's shoulder, but they
still have no recorder of their own and are cable-bound.
ENG cameras
ENG video cameras are similar to consumer camcorders, and indeed the dividing
line between them is somewhat blurry, but a few differences are generally
notable:
They are bigger, and usually have a shoulder stock for stabilizing on
the cameraman's shoulder
They use 3 CCDs
They have removable/swappable lenses
All settings like white balance, focus and iris can be manually adjusted,
and automatics can be completely disabled
If possible, these functions will be even adjustable mechanically (especially
focus and iris), not by passing signals to an actuator or digitally dampening
the video signal.
They will have professional connectors - BNC for video and XLR for audio
A complete timecode section will be available, and multiple cameras can
be timecode-synchronized with a cable
Finally, they will use a professional medium like some variant of Betacam
or DVCPRO, though some professional DV cameras are available, Canon's
XL1/XL2 and Sony's VX2100 cameras being examples.
Dock cameras
Some manufacturers build camera heads, which only contain the optical
array, the CCD sensors and the video coder, and can be used with a studio
adaptor for connection to a CCU or various dock recorders for direct recording
in the preferred format, making them very versatile. However, this versatility
leads to greater size and weight, and dock cameras have become rare in
recent years.
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