‘Colour temperature’ describes the feeling or appearance of how warm (red) or cool (blue) a certain type of illumination appears to be. It is measured in Kelvin (K).
Digital camera technology allows digitally produced video media to be altered as required to ‘gain’ colour and contrast in order to produce the desired colour quality. The required colour temperature range varies depending on the stadium illuminance level, with the minimum and maximum across all levels being 4,200K and 6,200K respectively.
It is often necessary to start broadcasting a football match in daylight and finish with all pitch illuminance provided by the floodlighting system. On these occasions, the artificial lighting should generally be used at the start of the broadcast to allow a gradual change from daylight to artificial illuminance. During this period, the broadcast engineers will be able to make gradual minor adjustments to the camera settings as required.
The diagram below provides a guide to the colour temperature range required for UEFA stadiums.