Q: I recently noticed what looks like a camera high up on a lamppost at the intersection of 145th Street and St. Nicholas Avenue, near where I live. What gives?

A: Don’t worry, Big Brother isn’t watching you, just your license plate should you run a red light.

The city’s Department of Transportation has been using cameras as part of its Red Light Camera program at busy intersections throughout the city since 1993, at a cost of between $45,000 to $55,000 a site, a spokesman for the Department of Transportation, Craig Chin, said.

The Red Light Camera program targets drivers who run red traffic signals. When this occurs, the cameras are used to identify the drivers’ license plates and a summons is mailed to them. The city has 75 locations set up for cameras, though state law limits the number of cameras that can be used to 50 at any one time. The department has been actively lobbying state officials to increase the number of cameras they use, Mr. Chin said. For security reasons, department officials won’t give out specific locations of the cameras.

The cabinet that is used to house a camera on the corner of 145th Street was manufactured by Auto Patrol, the company that made the film cameras no longer in use by the department, which has since upgraded to digital video cameras built by American Traffic Solutions.

So why is the old Auto Patrol cabinet still there? The department kept the old cabinet that houses the camera. Whether there is a camera inside is anybody’s guess.

The city has installed 200 “dummy cameras” that are actually empty cabinets meant to deter drivers from running red lights.