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Red Light Cameras being abused again in FLA.

  1. May 14, 2013 #1


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    Cutting yellow light times increases revenue but decreases safety.


  2. jcsd
  3. May 16, 2013 #2


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    But, without the additional revenue, the traffic companies won't have the funds to educate the legislators with campaign contributions.
    Somehow, I think that the economic benefits take up a larger part of the conversations. :rolleyes:
  4. Jun 2, 2013 #3
    Misapplied Physics of the Amber Light

    The reason why red light cameras are so profitable is because traffic engineers use a physics formula which they misunderstand. In their misunderstanding, they misapply physics to traffic situations systematically forcing motorists to inadvertently run red lights.
    Last edited by a moderator: Jun 3, 2013
  5. Jun 2, 2013 #4


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    There's never a valid excuse for running a red light, I've never "accidently" run a red light. It's because when people see a yellow light, they think it means "keep going you fool, the light's about to turn red. I've seen people speed up trying to beat the light instead of stopping. I've stopped without a problem and the car that tried to outrun the light was a bit behind me in the other lane. I've seen near rear ends caused by people that stopped when the light turned yellow and the car behind assumed that they would keep driving.
    Last edited by a moderator: Jun 3, 2013
  6. Jun 3, 2013 #5
    Most of the citations in Tucson go to people turning left with the green arrow. As a matter of fact only intersections with two left turn lanes have cameras. Most people get caught up by .2, 2/10th of a second.

    The legal point of entry into an intersection is a line dawn from opposite curbs on the same side of the intersection. Cameras are only located at intersections with odd ball entry points. No two have the same distance out from the crosswalk to that line.



    Try making a quick stop in front of the crosswalk when the yellow comes on and you will ultimately be rear ended (been proven). Stopping on the crosswalk is not legal.

    Once on the crosswalk no light can be seen except the one off to the right and on the opposite side of the intersection which may be up to 150 ft. away. A driver is expected to look off to the right while turning left and stay in the correct lane all at the same time.


    The picture above is a screen capture of an actual citation video. The DivX player allows a freeze frame. This picture resulted in my daughter in laws citation being dismissed by the judge.

    The word WAIT has been removed because it was not standard traffic signage. It also confused the bejeezes out of people.

    No red light comes on, all red lights are already on, the yellow simply goes out.

    There is no safety factor at the end of the left turn with the green arrow cycle the lights stay red in all four directions for traffic to clear the intersection.

    The cameras are operated by American Traffic Solutions. The citations are sent in the mail.

    Prior to the installation of the cameras if a vehicle was on the crosswalk and the yellow arrow was still on the driver could legally proceed with the turn. The City admitted they made a mistake by requiring the public to educate themselves on the new law.

    Oddly enough if a person is making a left turn or going straight through a non camera intersection where a policeman is present the old law still is in effect.
    Last edited: Jun 3, 2013
  7. Jun 3, 2013 #6
    Correction the third picture is not a screen capture. The screen capture function would not work. I had to take a picture of the screen with my camera.

    By law the yellow light must be on at least three seconds. It was later determined that the private company which operates the cameras had cut the length of the yellow by 1/2 second.
  8. Jun 3, 2013 #7


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    It appears to me that she would have had time to stop in 2.5 seconds since she is just beginning to enter the intersection and the light is already red. It appears she didn't try to stop when she saw the yellow light.
  9. Jun 3, 2013 #8


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    Then you must be very very quick when it comes to decision making. I am not. I am plagued with the inability to quickly make a decision where the answer isn't obvious to me. Also I suck at telling distance/time in real life circumstances. I literally don't know what to do sometimes. Occasionally I'll start to hit the breaks, and then let off after a quarter second, thinking that there's no way I can stop without screeching to a halt, when in reality I probably could have stopped without locking up my tires.

    I admit that there are times where I just don't want to stop, but it infuriates me to no end when I can't seem to make a quick decision and end up nearly running a red light.
  10. Jun 3, 2013 #9
    Yes, the studies show that people without Evo's apparently cyborg reflexes, i.e. most people, do better with longer yellow times, since one has to make a judgement call based on velocity and proximity to the light. Yellow doesn't mean "stop." It simply means "almost red." If you're 1 second away from the light at 40 mph, you keep going unless you want to get rear-ended.

    This is about revenue, not safety.

    -Dave K
  11. Jun 3, 2013 #10


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    I will chime in only to add that this strikes me as an oversimplification. In New Hampshire (at least, maybe elsewhere) we have traffic lights on 50MPH roads. In the winter, stopping for them can be MUCH more hazardous than coasting through.

    You could argue that you shouldn't be going that fast under those conditions, but even at 30MPH and at a coefficient of kinetic friction less than 0.001, stopping for a yellow light isn't always the smart option. This is doubly true if there are cars behind you. Our state vehicle inspections happen yearly and do not mandate snow tires in winter. I always have them, but others may not.
  12. Jun 3, 2013 #11

    D H

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    The converse is also a problem, people who come to a stop at a yellow when they should not have done so. Those overly cautious drivers cause accidents. The driver who slams on his breaks upon seeing the light turn yellow and just barely comes to a stop at the stop line, but then sees the light stay yellow for a second or more: That's an overly cautious driver who causes accidents. There's a happy medium of being neither overly cautious nor overly overly aggressive.

    On the other hand, if that same driver sees the light turn red just as he comes to a stop: That's a sign that the city that has set the timing of the yellow too short. This is a big problem. It turns nominally prudent drivers into scofflaws. It makes many drivers think along the lines of "If I have to slam on my brakes, thereby endangering the lives of my passengers, just to obey the law, I'm not going to obey the law." Unfortunately, these drivers now start applying that kind of thinking to every traffic law. One of the worst unintended consequences of the nationwide 55 MPH speed limit was creating a generation of traffic scofflaws.
  13. Jun 3, 2013 #12
    It takes a driver 1 full second to make the whoa or go decision, that leaves just one and one half seconds.

    Look again. As I mentioned all lights are already red during the entire left turn with the green arrow cycle. The yellow arrow is still on in the picture with the front of the vehicle on the line.

    One of the problems is that people tend to naturally go on through if they are already passed the crosswalk. That was legal for many years. The only light they can see once on the crosswalk is the faint arrow off to the right and on the other side of the intersection.

    It isn't just about my daughter in law it is about thousands of people, my wife included. It was my wife's only citation ever.

    The big gimmick involves human perception. The people who are turning left are slowing down and do not cover as much distance as their mind perceives that they will.

    I have spent nearly three years on this along with an a few other people. I have rubbed the city councils nose in it at public meetings on several occasions. The length of the yellow light was recently lengthened to 3 1/2 seconds.

    Those cameras are also speed cameras. They don't trigger unless the vehicle is going at least 11 MPH over the limit.?? I can blast through a 45 mph intersection at 55 mph and not be cited. No police officer would ever give anyone 10 mph over the limit. I do not understand the logic behind the allowed 10 mph over the limit.

    There is no safety factor in the left turn situation only a money factor.

    The cameras are pointed directly at the left turn lanes. After many hours of observation and picture taking I have never seen a camera flash a speeding vehicle or a vehicle travelling straight through the intersection.

    As I was watching the video of my wife's citation I counted three vehicles that turned right on red without stopping. That is definitely a safety factor but the cameras don't point that direction.

    Though all of this I think the idea of the cameras is fine, but they have to be honest.

    Edit: The round lights at the top are actually the red lights. They don't look red in the picture.:redface:
    Last edited: Jun 3, 2013
  14. Jun 3, 2013 #13


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    With a coefficient of friction of less than 0.001, you should stay at home. There is no way to drive a car like that. You would need 15 minutes and 4 km (2.5 miles) to accelerate to 32km/h (20mph).

    You need 1 second if you are surprised by something. If you drive towards traffic lights, you shouldn't be surprised by them. Let's take 1/2 second to react:
    45mph = 20m/s? Therefore, if you are less than 40m away from the intersection, you can drive through.
    A smooth stop from that velocity needs about ~50m and 5 seconds. This leaves a range of 10m where you have to hit the brakes a bit more than usual. With 3 seconds (the minimal time according to US-laws?), this region disappears, and if you make the right decision you are fine. Note that you do not have to make this decision at the time the traffic lights get yellow - you can think about that in advance.

    In Germany, we have a recommended (and used) time of 3 seconds for 50km/h (30mph), 4 seconds for 60km/h (37mph) and 5 seconds for 70km/h (43mph). Using the same values as above, this leaves a lot of time to make a decision.
  15. Jun 3, 2013 #14
    My grand uncle, if you will, was a Brooklyn city cop for 30 years (eventually made lieutenant). While off duty, he got pulled over from time to time over the years, as we all do. However, he said that all he had to do was flash his "shield," as they call it, when he got pulled over, and all that would commence henceforth were a few high-fives and he's be on his way. He's still alive by the way and fully enjoying his retirement. I'm hoping I'm mentioned in his will...

    Anyway, I digress. There was one occasion in the politically correct 90's where flashing his shield didn't work, and he had to go to court to fight the ticket. He told the judge that, in his judgment, slamming on the brakes to yield to the yellow light would have been more dangerous than simply going through the intersection. It worked and he got the ticket dismissed. So I always remembered that argument, although I never had a chance to use it.

    The point is moot, though, because I have the best traffic attorney in Washington State, which is a police state when it comes to vehicle infractions. She is the "Saul Goodman" of the traffic courts and made a few tickets "go away" for me, including one at a "photo safe" intersection where big brother thought he cornered me :tongue:
  16. Jun 3, 2013 #15
    Fast forward this video to 7:20. Wouldn't it have been great to hang out with Voltaire and the "crew" in Lady du Ch√Ętelet's court? I'm bringing the Pizza!

  17. Jun 3, 2013 #16
    My (non respectful of authority) dad always used to say "What do you call a guy who hides behind the bushes with a gun, and jumps out and takes your money?" "A cop."
  18. Jun 3, 2013 #17
    The problem is that Americans generally regard driving as a nuisance rather than something you're supposed to actually pay attention to doing. 3 seconds may be enough if you are actually paying attention and not drinking/smoking/talking on the phone, but we don't know how to do that here.(For years Americans were frustrated that their german built cars didn't come equipped with cupholders.)
    We (the US) need to adopt Germany's rigorous standards for driving (as in taking lots of tests and paying lots of money before you can drive, and the insistence on driving correctly rather than just going slower.) I'm sure you find that a pain in the but, but if you've ever seen how people drive here...

    -Dave K
  19. Jun 3, 2013 #18
    What are you talking about?! A car with no cupholders? My Kia Rio has 3, and my Taurus has 4, with the pullout trick from the dash. I seem to use every single one of those holders for one purpose or another...
  20. Jun 3, 2013 #19


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    Not always, a similar situation occurred in San Diego, California, where the yellow light durations at certain intersections were repeatedly reduced to below California standards that take reaction time and speed into account in order to increase revenue from the red light cameras. Note that reaction time for standards is increase to take into account distractions, such as checking for pedestrians in crosswalk, or scanning for vehicles that could end up colliding with the left turn driver's car. In some case the yellow light duration was reduced to below what is required for a large truck to be able to stop in time assuming an average driving reaction time of about .75 seconds. This is the reason for the "2 second" or "3 second" recommended following time when driving in traffic.

    There was some type of court case, and the yellow light durations were restored, and at least some of the "sub-standard" tickets were dismissed.

    In that image, the left turn arrow is yellow. There is no red left turn arrow, only the red light that is above the yellow left turn arrow.
  21. Jun 3, 2013 #20


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    Ah, yes, I missed the yellow arrow, so people were given more time to turn left. Then I agree, she was ok. This wasn't an issue of the yellow light not being on long enough. We have those lights where you have a red for going straight, but green for turning.

    I'm more like what MFB described, I know already how I will react to a yellow light, I do check behind to see if some maniac is gaining on me when approaching a light, sometimes changing lanes to let them run the light. If I have no choice between getting rearended and possibly running a yellow/red light, obviously I will have to make that choice, but that's hardly ever, and it's no "accident".

    My daughter was driving my new car a couple of years ago when a teenager ran a left turn red light and plowed into her, totaling my car (she hit the engine part), destroying it. Luckily my daughter was only bruised and cut by the airbags deploying. The teenager had just gotten her car back a week from running into someone else.
  22. Jun 3, 2013 #21
    Your daughter's situation would not likely happen here. At the end of the left turn cycle all lights stay red in all directions for 2 seconds to allow traffic to clear the intersection. The turn arrows come on at the end of the straight thru cycle rather than at the beginning. This is supposedly for safety reasons.

    When they added enough time to the yellow so that people didn't get caught up in the "looking in three directions at the same time" situation citations dropped off dramatically. The income loss was offset by installing more cameras at more intersections.

    I am not against the cameras, but the abuse I have seen is inexcusable. They were intentionally playing on the inability of the human drivers to multitask visually.
  23. Jun 3, 2013 #22


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    It's hard to make money by just targeting the true traffic scofflaws so the incentive to lower the threshold of detection to the level of human error is understandable when the profit motive is involved. The profit motive must be removed to keep the focus on public safety, base the companies profit on the reduction of accidents and violations not the number of citations.
  24. Jun 4, 2013 #23
    Right, those aren't German cars.

    German cars didn't include cup holders for years because the manufacturers assumed that when people drive, they are driving, not drinking. They finally caved only in recent years to pressure from America.

    -Dave K
  25. Jun 4, 2013 #24
    Thank God...
  26. Jun 4, 2013 #25


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    Yep, and the cupholders in some of them (I'm looking at you, Porsche...) are still clearly pitiful afterthoughts that are basically useless.
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