# Traffic flow cameras

**URL:** <https://community.cartalk.com/t/traffic-flow-cameras/81513>\
**Category:** General Discussion\
**Created:** [September 26, 2013, 5:09am UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513 "2013-09-26T05:09:37Z")\
**Posts on this page:** 20\
**Page:** 1

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**Author:** ![bscar2](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bscar2/32/2468_2.png) [@bscar2](https://community.cartalk.com/u/bscar2)\
**Post date:** [September 26, 2013, 5:09am UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/1 "2013-09-26T05:09:37Z")

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the recent discussion on the flashing yellow arrow reminded me of the new set up my town got on the eastern part of the city.  
Apparently, ODOT funded new traffic lights on state route 95 near the US 23 junction. With the new lights came cameras that are, supposedly, setup to monitor traffic flow and adjust the lights so the timing helps keep traffic moving.  
Some think they’re actually red light cameras, but I read that they must inform you of the cameras. Also, house bill 69 pretty much outlawed red light cameras in Ohio  
[http://www.dot.state.oh.us/districts/D06/news/Pages/Safety-Improvements-Coming-to-Marion’s-SR-95.aspx](http://www.dot.state.oh.us/districts/D06/news/Pages/Safety-Improvements-Coming-to-Marion%27s-SR-95.aspx) (march of this year, before they installed the new lights)  
[http://www.dispatch.com/content/stories/local/2013/06/26/House-passes-red-light-camera-ban.html](http://www.dispatch.com/content/stories/local/2013/06/26/House-passes-red-light-camera-ban.html) (article about the bill to ban cameras)

Are there any cities out there that have these cameras like we do? Do they really help traffic flow?

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**Author:** ![bing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bing/32/4619_2.png) [@bing](https://community.cartalk.com/u/bing)\
**Post date:** [September 26, 2013, 9:08am UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/2 "2013-09-26T09:08:07Z")

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Minneapolis/St. Paul has about a zillion cameras on the main freeways to montor traffic. South Dakota has some state-wide. Its nice because you can get on line and check traffice and even road conditions. They also use sensors imbedded in the road. They can detect speed in the traffic center but for traffic info not enforcement. We’ll be on our way to Columbus again probably next week.

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**Author:** ![Whitey](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/whitey/32/24680_2.png) [@Whitey](https://community.cartalk.com/u/Whitey)\
**Post date:** [September 26, 2013, 6:28pm UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/3 "2013-09-26T18:28:01Z")

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Where I live, Stuart, Florida, there are cameras like those at every major intersection. I don’t know if they use them to monitor traffic flow and adjust the lights (I don’t see evidence of this during rush hour) or if they only use them when they are trying to find someone, but they don’t use them as red light cameras.

Personally, I am glad the cameras are there. Their presence alone discourages people from running red lights because they know any collision will be recorded, and fault will be easy to pinpoint. Anyone who has read Orwell’s _1984_ knows the difference between Big Brother and surveillance cameras in public spaces. There is no reason to expect privacy at a public intersection.

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**Author:** ![Caddyman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/caddyman/32/23_2.png) [@Caddyman](https://community.cartalk.com/u/Caddyman)\
**Post date:** [September 26, 2013, 6:39pm UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/4 "2013-09-26T18:39:17Z")

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With millions of these government cameras, do we pay millions of government employees to sit around a watch the images they produce 24/7 ??? Or is the output simply recorded on DVR’s and filed away in some vast data storage facility…

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**Author:** ![Whitey](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/whitey/32/24680_2.png) [@Whitey](https://community.cartalk.com/u/Whitey)\
**Post date:** [September 26, 2013, 8:47pm UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/5 "2013-09-26T20:47:44Z")

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@Caddyman, I’m pretty sure it varies by city/town, but I’m pretty sure facial recognition software has made the process easier. I know the cameras where I work are not monitored by anyone unless the officer on duty happens to be looking at the monitor.

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**Author:** ![TwinTurbo](https://avatars.discourse-cdn.com/v4/letter/t/8baadc/32.png) [@TwinTurbo](https://community.cartalk.com/u/TwinTurbo)\
**Post date:** [September 26, 2013, 8:51pm UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/6 "2013-09-26T20:51:25Z")

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They use the cameras here to display on large informational signs what you can expect for travel time between major points coming in to the cities. It is all automated. When approaching the typical congestion points, you can see on a large sign where the actual travel time is displayed along with the time it was last updated. About every 5 minutes, it gets updated. If an accident happens, that is also displayed. So coming in to work you might see I95 point X to point Y 10 miles 10 minutes. Very helpful IMO.

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**Author:** ![jtsanders](https://avatars.discourse-cdn.com/v4/letter/j/c2a13f/32.png) [@jtsanders](https://community.cartalk.com/u/jtsanders)\
**Post date:** [September 27, 2013, 1:31am UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/7 "2013-09-27T01:31:52Z")

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The cameras I’ve seen in MD monitor traffic on major highways. If you are driving thro ugh MD. And want to see what traffic is like, do a web search for MD Chart. At a rest stop, of course. You can get traffic reports too.

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**Author:** ![bing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bing/32/4619_2.png) [@bing](https://community.cartalk.com/u/bing)\
**Post date:** [September 27, 2013, 2:17am UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/8 "2013-09-27T02:17:23Z")

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In Minneapolis/St. Paul they are monitored by live bodies in the control center. Just for traffice flow though. You really can’t see much else on them.

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**Author:** ![bscar2](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bscar2/32/2468_2.png) [@bscar2](https://community.cartalk.com/u/bscar2)\
**Post date:** [September 27, 2013, 2:21am UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/9 "2013-09-27T02:21:28Z")

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The area they put the new lights and such in is pretty busy at most times of the day, and it’s a road I avoid as much as possible, and I can tell you several ways to get to the places out there without actually driving on sr95 very much, or at all.

In the last 5~6 years that end of town has blown up with businesses opening up. For the longest time, a farmer owned the land out there and refused to sell it to the city. When he died, his children sold it, and it’s been booming ever since.

@TwinTurbo the section of road that they done isn’t large enough to warrant a sign like that; it might be a mile long, if that.

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**Author:** ![keith](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/keith/32/5518_2.png) [@keith](https://community.cartalk.com/u/keith)\
**Post date:** [September 27, 2013, 9:13am UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/10 "2013-09-27T09:13:30Z")

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They use them here as well, mostly they feed video to the news outlets for their traffic reports but they can also be used to estimate time to various major interchanges on those automated billboards as Twin Turbo said. It doesn’t appear that their resolution is good enough to track anyone.

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**Author:** ![bscar2](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bscar2/32/2468_2.png) [@bscar2](https://community.cartalk.com/u/bscar2)\
**Post date:** [September 27, 2013, 12:54pm UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/11 "2013-09-27T12:54:00Z")

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[http://www.10tv.com/content/stories/2013/09/26/marion-traffic-cameras.html](http://www.10tv.com/content/stories/2013/09/26/marion-traffic-cameras.html)

> The Marion Police Department is assuring drivers that new traffic cameras around town will not result in traffic tickets.
> 
> Police said the cameras are detectors that trigger the traffic lights to change.
> 
> The department stresses that the devices are not red light or speed cameras and they cannot be used for traffic enforcement.

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**Author:** ![jtsanders](https://avatars.discourse-cdn.com/v4/letter/j/c2a13f/32.png) [@jtsanders](https://community.cartalk.com/u/jtsanders)\
**Post date:** [September 27, 2013, 7:25pm UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/12 "2013-09-27T19:25:14Z")

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There are many types of cameras. The traffic light control camera would have to resolve license plates to provide evidence for a ticket. It would also need a computer that can tell the difference between a car sitting at a light and one moving through it. I had my picture taken a a red light camera near work while I was stopped at the light. But I never received a ticket. The cameras in Marion might be infrared to just detect the heat of the car, for instance. You could ask the city for more details on the cameras if knowing why they can’t read plates is important to you. Of course, if these cameras can read plates. Expect that some time in the future they will be red light cameras.

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**Author:** ![TwinTurbo](https://avatars.discourse-cdn.com/v4/letter/t/8baadc/32.png) [@TwinTurbo](https://community.cartalk.com/u/TwinTurbo)\
**Post date:** [September 27, 2013, 8:53pm UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/13 "2013-09-27T20:53:29Z")

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These systems span the range of sophistication from simple cameras with separate triggers to high end, standalone, low lux detector arrays with microprocessor imaging firmware to detect motion and even clean up images that are taken before transmitting them back to home base.

Most LPR systems use infrared illuminators that take advantage of the paints used on the license plate. The problem with IR light for occupant illumination is that very high power output is required to penetrate and illuminate the occupants and that becomes an eye safety issue. Your eye does not detect these wavelengths and therefore your blink reflex is not triggered.

Naturally, you have a separate safety issue if someone is driving by and a bright flash of visible light goes off unexpectedly. So they choose illumination wavelengths that avoid these issues and block the visible using absorptive filters.

Anyway, there are low end systems that could never be used for anything but low res, motion detectors. But there are also high end systems that could be used in less demanding applications today but later be repurposed to provide additional capabilities.

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**Author:** ![oblivion](https://avatars.discourse-cdn.com/v4/letter/o/3ab097/32.png) [@oblivion](https://community.cartalk.com/u/oblivion)\
**Post date:** [September 30, 2013, 2:51am UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/14 "2013-09-30T02:51:53Z")

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@TwinTurbo: IR radiation is at the lower end of the visible spectrum and lacks the energy to damage your retina, unless very concentrated, such as in an IR laser, unlike higher frequencies, such as UV light. Also, it would reflect or be scattered by auto glass, making it very difficult to illuminate occupants inside the vehicle with any degree of clarity. You’d reach a point of diminishing returns I think, long before you got to a level that is harmful. You’d likely feel it as heat long before that.

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**Author:** ![TwinTurbo](https://avatars.discourse-cdn.com/v4/letter/t/8baadc/32.png) [@TwinTurbo](https://community.cartalk.com/u/TwinTurbo)\
**Post date:** [September 30, 2013, 8:04am UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/15 "2013-09-30T08:04:49Z")

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@oblivion

You’re absolutely right. The second half of my post was supposed to be about UV illuminators but looks like I got that all messed up. We design and manufacture both.

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**Author:** ![bscar2](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bscar2/32/2468_2.png) [@bscar2](https://community.cartalk.com/u/bscar2)\
**Post date:** [October 1, 2013, 3:27am UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/16 "2013-10-01T03:27:47Z")

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I’ve seen a couple of the new lights setup(not active as of yet, though) and the cameras aren’t very big; little bit bigger than my hand, from the looks of it.

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**Author:** ![jtsanders](https://avatars.discourse-cdn.com/v4/letter/j/c2a13f/32.png) [@jtsanders](https://community.cartalk.com/u/jtsanders)\
**Post date:** [October 1, 2013, 4:25am UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/17 "2013-10-01T04:25:32Z")

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I heard a new twist on traffic cameras today. Police cruisers have cameras on the front fenders. Thy take pictures of license plates and check for criminal activity while they cruise the streets. One policeman said he found 9 stolen cars that way; there’s good and bad. But it still gives me the creeps.

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**Author:** ![Whitey](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/whitey/32/24680_2.png) [@Whitey](https://community.cartalk.com/u/Whitey)\
**Post date:** [October 1, 2013, 4:32am UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/18 "2013-10-01T04:32:16Z")

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@jtsanders, those cruiser-mounted cameras are just automating what police officers were already doing manually with their eyes, hands, computers, and radios. The camera scans the license plate, runs it, and alerts the officer if the owner has any outstanding warrants, if the car has been reported stolen, the registration is expired, etc. Isn’t that why we have license plates in the first place?

I’m cool with it, not because I don’t have anything to hide, but because I have no expectation of privacy on public roads driving a car that is registered with the state.

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**Author:** ![DrRocket](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/drrocket/32/2603_2.png) [@DrRocket](https://community.cartalk.com/u/DrRocket)\
**Post date:** [October 1, 2013, 5:55am UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/19 "2013-10-01T05:55:10Z")

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The big discussion up here regarding those plate scanner cameras is how long the police departments keep the info scanned. Some PDs here only keep the data for a week or so, others were holding onto it indefinately, which, of course, had the privacy advocates pretty upset.

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**Author:** ![bing](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/bing/32/4619_2.png) [@bing](https://community.cartalk.com/u/bing)\
**Post date:** [October 1, 2013, 6:12am UTC](https://community.cartalk.com/t/traffic-flow-cameras/81513/20 "2013-10-01T06:12:29Z")

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They’ve been doing the plate scanners in Minneapolis/St. Paul for quite a while. It not only looks for stolen vehicles but it records where everyone is and when. The big deal this last session was that they kept the information over a year and of course access by a $10 an hour clerk. The point was they knew and had files on where every car was and what time for no apparent reason except at some point trying to reconstruct criminal activity.

Now I don’t do anything wrong, but it just plain is no one’s business where I am and certainly not filed away for at least a year in the computer. Give them a little tool to help fight crime and they just go bonkers. Of course they’d never be able to afford all the high tech without the help of Homeland Security money. No money for white house tours but plenty for plate scanners.

[Next page](https://community.cartalk.com/t/traffic-flow-cameras/81513.md?page=2)
