Quote: Originally posted by TomS on 26 November 2004
I though the camera only triggered when a car has gone past a certain distance after the lights (like 5 metres)!!
1 metre! thats ridiculous!!
Red light cameras are placed at traffic light controlled junctions and photograph vehicles that pass traffic lights set to red. The camera is triggered from inductive proximity sensors placed within the road surface. The detector triggers when a car passes over the loop - if the traffic light is also set to red, then the camera is triggered to take two photographs 1 second apart. A data box is included in the photograph to show the date and time of the photographs, the speed of the vehicle as it passed the red light and, if necessary, a road lane idenification.
http://www.stvincent.ac.uk/Resources/Physics/Speed/road/redlt.htmlhttp://www.stvincent.ac.uk/Resources/Physics/Speed/road/redlt.html