Abstract: A portable controlled lighting system comprising at least one lamp connected to an operating circuit for operating the lamp and a control circuit coupled to the operating circuit for controlling the luminous flux of the lamp is disclosed. A battery pack for providing electrical power to the operating circuit is also provided, together with a control means for adjusting the luminous flux of the lamp by the control circuit. The control means comprises a first adjustment means for controlling the luminous flux of the lamp and provides a predetermined rate of increase of the luminous flux until a predetermined flux level is achieved.