The camera control unit is typically part of a live television broadcast chain. It is responsible for powering the professional video camera, handling signals sent over the camera cable to and from the camera, and can be used to control various camera parameters remotely.
Before cameras became self-contained units, broadcast cameras required vast racks of control units just to generate a usable picture. In outside broadcast production, these racks took up an entire section of the OB truck and were operated by a small team of skilled engineers. These vision engineers had two roles. Firstly, they set up the CCUs at the start of production and ensured that the picture created was of broadcast quality. This process included a lengthy 'lining up' process in which the vision engineer would work with the camera operator, to adjust the settings on both the actual camera and the CCU in tandem. During production, it was the vision engineers' job to operate the CCUs and control both the exposure and the color balance. So skilled and labor-intensive was this role that each CCU required its own dedicated vision engineer.
Modern cameras are typically more self-contained than their predecessors and many can operate without a CCU. Even when not required, a CCU can be of benefit for the following reasons: