What does it mean to take photos at a speed limit and illegally take photos on the expressway?

The difference between the two is that illegal photography will be fined, and speeding photography will not be fined if it is not speeding. Taking photos in violation of regulations refers to taking photos in violation of regulations with electronic eyes in traffic. Its working principle is that the electronic eye senses the pressure from the car on the road by using the sensing wire, and the signal is collected by the sensor to the central processor and sent to the register for temporary storage (the data is valid during the red light period).