Jim Yanik
Yeah, at rush hour these won't do too much for catching people, but the deterrent effect is the same. Many people don't pay enough attention to know about the 15 mph thing, and those who do might not be sure if they're going 12 or 17.
What happens since they fixed the light timing is since the next light is green, people floor it even on a left cause they see open space, which means sometimes cars are going 20-25 mph, just to slam on their brakes almost as soon as they clear the intersection. I was hit that way once, a girl revved up to make a yellow and didn't stop till she'd driven into the back of my car.
If these cameras were all about revenue, as you all keep claiming, they obviously wouldn't have the 15mph requirement in place. The idea is that impacts at over 15 mph are much more dangerous, so they want to at least deter high speed light running even at off peak hours. Another perk is that it lets right on red occur without snapping a picture, while still making sure you're doing so at least somewhat reasonably.
I've come to look at it as the red light toll - if you're so self-absorbed that you run red lights, you must be willing to pay a toll to do so.
Dave