Red light camera on a yellow light 

I had a red light camera take my picture on the corner of Hall and Scholls Ferry Rd around 9:30pm on 4/21/2015. My dashcam recorded it. I was looking in my mirrors at the car that had just crossed my path and didn't see the yellow until I was too close and had to go thru it. The red light camera went off. After watching the video, though, IT WAS YELLOW AND NEVER RED. According to the Beaverton Police Department website, a driver will only get a ticket if the driver entered the intersection AFTER it turned RED. The light was not red, so why did it take my picture?
I'm posting this as proof in case I get a ticket in the mail.
Note: The timestamp on my dashcam is wrong. It thinks it's about a day later than it actually is.
Quote from the Beaverton Police Department:
"Drivers are only ticketed via the camera system for entering the intersection after the light has turned RED. If you enter a photo red light intersection on a green or yellow light you will not be ticketed by the camera system. However, if a Beaverton Police Officer is present and observes a vehicle entering on a yellow light, and the officer believes the driver should have stopped before entering the intersection, then the police officer is authorized to issue a ticket for entering a yellow light."
www.beavertonor...