Want this question answered?
150 meters
You must dim your high-beams if you're within 500 feet of an approaching car and dim your high-beams within 300 feet of the vehicle you follow.
500 feet
500'
When you are within 500 feet of an oncoming vehicle or you come up behind a vehicle.
If you can see his headlights, drop your high beams. In some states its the law 300 feet at least.
500 feet.
Be considerate in using your high beams. Your headlights must be on low beam when you are within 500 feet (150 m) of an approaching vehicle, or within 200 feet (60 m) of a vehicle ahead of you, even if the vehicle ahead is in a different lane. You should also dim your lights for pedestrians approaching you. http://www.nydmv.state.ny.us/dmanual/chapter10-manual.htm (Alaska and Oregon are the same as New York - 500 feet.)
I like to switch around 200-300 feet away from them
the answer is approx, 350 feet. if they are standard head lights.
Think of it this way, when you see a vehicle. more then likely it sees you, so try to lower the high beams as soon you realize another vehicle is infront of you. The law in Oregon is 350 feet.
A quarter mile. If not correct answer - change the law. California law states - Your high beams have to be dimmed within 300 feet of following another driver and within 500 feet of an oncoming driver.