Description

The Camera Control Unit is typically part of a live television

Live television

Live television refers to a television production broadcast in real-time, as events happen, in the present. From the early days of television until about 1958, live television was used heavily, except for filmed shows such as I Love Lucy and Gunsmoke. Video tape did not exist until 1957...

 broadcast "chain". It is responsible for powering the professional video camera

Professional video camera

A professional video camera is a high-end device for creating electronic moving images...

, handling signals sent over the camera cable (multicore cable

Multicore cable

An audio multicore cable is a cable which contains from 4 to 64 individual audio cables inside a common outer jacket. Audio multicore cables are widely used whenever multiple audio signals, for example from a number of microphones, need to be conveyed between common locations...

, triax or fiber

Fiber

Fiber is a class of materials that are continuous filaments or are in discrete elongated pieces, similar to lengths of thread.They are very important in the biology of both plants and animals, for holding tissues together....

) to and from the camera, and can be used control various camera parameters such as iris remotely.

Broadcast cameras typically carry several signals over the camera cable in addition to the camera output itself.

Typically, RGB signals are transmitted over the camera cable. The CCU will usually convert these to SDI, YUV or composite for interfacing to other video equipment.

Advantages over using independent cameras with automatic settings

• In a system with multiple-camera setup
  Multiple-camera setup
  The multiple-camera setup, multiple-camera mode of production, or multicam is a method of filmmaking and video production. Several cameras—either film or professional video cameras—are employed on the set and simultaneously record or broadcast a scene...
  
  , the cameras can be "matched" - made to look the same in terms of colour balance and picture intensity without having to ask the camera operator to

• The camera operator
  Camera operator
  A camera operator or cameraman is a professional operator of a film or video camera. In filmmaking, the leading cameraman is usually called a cinematographer, while a cameraman in a video production may be known as a television camera operator, video camera operator, or videographer, depending on...
  
  s are freed from the control of iris and black level - leaving them free to concentrate on other aspects of camerawork such as blocking and image composition

• All signals that operate between the camera and CCU are carried in one multicore cable.

Scope of CCU functions

A CCU is typically able to control the following camera parameters remotely:

• Iris (see aperture
  Aperture
  In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture of an optical system is the opening that determines the cone angle of a bundle of rays that come to a focus in the image plane. The aperture determines how collimated the admitted rays are,...
  
  )
• Color temperature
  Color temperature
  Color temperature is a characteristic of visible light that has important applications in lighting, photography, videography, publishing, manufacturing, astrophysics, and other fields. The color temperature of a light source is the temperature of an ideal black-body radiator that radiates light of...
  
   filters
• Neutral density filter
  Neutral density filter
  In photography and optics, a neutral density filter or ND filter can be a colorless or grey filter. An ideal neutral density filter reduces and/or modifies intensity of all wavelengths or colors of light equally, giving no changes in hue of color rendition.The purpose of standard photographic...
  
  
• Master Black (pedestal)
• Black level trim (for red, green and blue components)
• Gain trim (for red, green and blue components)
• Master gain

In addition to these, there are usually options for switching in a cable test filter.

Connections to a CCU

Typical signals can be both digital signal

Digital signal

A digital signal is a physical signal that is a representation of a sequence of discrete values , for example of an arbitrary bit stream, or of a digitized analog signal...

 and analog signal

Analog signal

An analog or analogue signal is any continuous signal for which the time varying feature of the signal is a representation of some other time varying quantity, i.e., analogous to another time varying signal. It differs from a digital signal in terms of small fluctuations in the signal which are...

s:

• Video out (Serial digital interface
  Serial Digital Interface
  Serial digital interface is a family of video interfaces standardized by SMPTE. For example, ITU-R BT.656 and SMPTE 259M define digital video interfaces used for broadcast-grade video...
  
   (SDI)
• Video out (composite video
  Composite video
  Composite video is the format of an analog television signal before it is combined with a sound signal and modulated onto an RF carrier. In contrast to component video it contains all required video information, including colors in a single line-level signal...
  
  )
• Video out (component video
  Component video
  Component video is a video signal that has been split into two or more component channels. In popular use, it refers to a type of component analog video information that is transmitted or stored as three separate signals...
  
  )
• Audio out (microphone
  Microphone
  A microphone is an acoustic-to-electric transducer or sensor that converts sound into an electrical signal. In 1877, Emile Berliner invented the first microphone used as a telephone voice transmitter...
  
   on board)
• Video in (genlock
  Genlock
  Genlock is a common technique where the video output of one source, or a specific reference signal from a signal generator, is used to synchronize other television picture sources together. The aim in video and digital audio applications is to ensure the coincidence of signals in time at a...
  
   in the form of color burst)
• Return video in (composite)
• Return video in (vision mixer
  Vision mixer
  A vision mixer is a device used to select between several different video sources and in some cases Compositing video sources together to create special effects...
  
   program out)
• Interruptible feedback
  Interruptible feedback
  IFB or Interrupted Feedback systems are used in filmmaking and video production for television crew communication, audio monitoring and cueing...
  
   Intercom
  Intercom
  An intercom , talkback or doorphone is a stand-alone voice communications system for use within a building or small collection of buildings, functioning independently of the public telephone network. Intercoms are generally mounted permanently in buildings and vehicles...
  
  
• Tally light
  Tally light
  In a television studio , a tally light is a small signal-lamp on a professional video camera or monitor. It is usually located just above the lens or on the so-called electronic viewfinder and communicatee, for the benefit of those in front of the camera as well as the camera operator, that the...
  
  trigger