 The advent of infra-red flash technology has provided Gatsos with the capacity to capture vehicles exceeding the limit in varying conditions - without emitting a bright flash, which in many cases can be considered distracting to the driver, especially if taken head-on.Infra-red light is invisible to the human eye, but when paired with a camera with an infra-red sensor, can be used as a flash to produce a clear image in low light conditions.Used only in Western Australia, this Doppler RADAR-based camera is mounted usually on a tripod on the side of the road.