Racks Engineer

A "Racks Engineer" is a British term for a television outside broadcast engineer who performs Vision Control Duties.  

Vision Control is the setting of a television camera iris, black level and colour balance, together with some other technical parameters.  On a multi-camera programme, the colour and brightness of viewed objects must look identical when viewing the same scene on several cameras.  

The term "racks engineer" originates from the birth of electronic television in the UK at Alexanda Palace when engineers sat on high stools or ladders next to the equipment racks housing the Camera Control Units (CCU).