when does a red-light camera take a photo ?

You're ok. I believe RLC sensor gets triggered when a car crosses the line(s) when the light is already red. You can cross the line when the light is yellow/amber without triggering the sensor.

In many states, you only violate the red light law if you cross the stop line after the light turns red. Some states may have a provision which says you must stop on yellow if you safely can, but as far as I know, red light cameras only enforce the first and stricter standard. So you should be fine, unless you were wrong about the color of the light when you entered the intersection. Most cameras work by snapping two photos (and yes, normally, you see flash, even in daylight), one while the light has turned red and you're still moving towards the intersection and the second after you've entered the intersection. Without two photos, or a video, that shows you crossed the line after the light changed to red, they really can't prove you entered the intersection illegally.

If I'm not mistaken, I believe that it takes the photo when it is in yellow still, just before to change to red. And I have seen that it take the photo when you are going to make a right and you don't make a full stop before turning.

The legal meaning of a yellow light varies with state law. However generally the only legal meaning of the yellow is a warning that the light is about to turn red. The length of the yellow is where they get you.

Also the definition of what is the "limit line" varies with the intersection. A painted limit line defines where the intersection begins.

Laws will vary between states and localities. Generally no violation has occurred until a vehicle enters an intersection when the light is red.

Most camera systems have been programmed to sense when a vehicle comes to a complete stop behind the limit line and then proceeds to make a right turn.

In most jurisdictions, if you are in the intersection when the light turns red, you can continue your maneuver without penalty. But then again, like all advice, this varies. The best bet is to seek a legal opinion from someone licensed to provide them.

State laws do vary...in Vermont if you enter the intersection on a yellow light you can receive a ticket. Also, FYI for you travelers...in VT you CANNOT turn right on a red arrow....it will cost you $156 and 2 points.

To me, that would seem obvious. That red right turn arrow by itself says stop and stay stopped until a green one shows up.

It take photo when you cross the intersection after the light turn red and it cost around $400 and 1 point in California. Not to mention traffic school fees to avoid the record.

My son asked about this when he encountered red arrow signals on a recent trip to Atlanta. We are not familiar with red arrow lights in our area, and the rules are apparently not all that obvious or consistent according to this article: http://www.johncletheroe.org/usa_can/driving/right.htm

I think that you're considered running the light if you cross the plane of the intersection after the light has turned red.

I was sitting out in the middle of the intersection, cut off mid-way through my turn and ended up having to wait until the light turned red before I could turn. It was a RLC intersection and I haven't gotten a ticket yet.

Agree. I think that's how it works

Heres your answer

http://auto.howstuffworks.com/red-light-camera.htm