Overhead Camera Work


Posted on Tuesday, October 10th, 2017 at 10:08 AM

Ever seen the cameras atop of signal lights and wonder what they’re for?
We asked, and this is what we were told:

MARK CLARK: “Cameras for triggering phases only, not connected to any traffic control center. Opticoms are the smaller units on the top of the mast arms, sometimes one or two, depending on type. Those are for emergency pre-emptions.

Not for red light running, not for vehicle identification. Red light cameras have a strobe and are typically mounted lower taking a different picture of the intersection. If the city did have a traffic operations center and wanted to wire them to it, you would get a typical video view. Not enough details to read license plates. Hard enough to pick up vehicles and shadows with our bright sun. Sometimes glare out, but cheaper and easier to repair than loops. Cameras replace loops – Don’t get damaged by road construction and utility work either. Cameras about 5K, and do an entire leg of an intersection. Loops have to be put in each lane (3 or 4 on a leg and area about 5k each, 15 to 20k a leg.

They can be used to count traffic if connected to the right type of controller and we do so at LH Avenue and McCulloch.”