A method and apparatus for wirelessly synchronizing operation of an image sensor of an endoscopic video camera unit having a wireless transmitter with operation of a portable endoscopic light source unit includes transmitting a message packet with a target camera shutter period, light source target phase/trigger time/OFF time and light source target ON time to the light source unit. The light source unit controls the start time and the ON time for light output by a light source. The video camera unit includes a light detector for detecting the actual light source start time and duration of light output to provide closed-loop feedback. A camera controller ensures synchronization between the shutter period of the image sensor and actual operation of the light source based on the actual phase and actual ON time sensed by the light detector and the previously communicated target phase/trigger time/OFF time and target ON time.