Traffic Camera Countermeasure

Don’t get us wrong, we drive very carefully as it’s the most dangerous thing we do on a regular basis. But even a careful driver can get caught by bad traffic and a red light camera. These are devices that monitor intersections. If you get caught in the middle when the light goes red they take a picture and you get a ticket in the mail. Well, that’s the way it used to be. This traffic camera countermeasure puts it to an end. As you can see, the noPhoto uses a flash of its own to overexpose traffic camera images.

The image above shows the prototype. The foil is reflecting a flash on either side onto the license plate using a flash sensor which acts as the trigger. According to the demo video after the break, the system can even defeat the pre-flash, and dual-photo types of cameras.

There are pretty tight restrictions on using lights on your vehicles (colors, placement, etc.). We wonder if this passes muster?

[via BoingBoing]

211 thoughts on “Traffic Camera Countermeasure

  1. If you’re going to block it, why not use a LCD blackout glass hooked up to a toggle switch and turn it off when you go into the intersection?

    Speaking of using lights to undermine the effectiveness, if you mount some lights in the front of the car and strobe them at a specific frequency, it’ll jam the laser in a radar detector….

    1. Yea I was thinking LCD, but it should be attached to the flash detector, if a cop sees your license blacked out for even a few seconds your toast, but a brief blip of black when the flash goes off, nobody would catch that.

  2. Take traffic out of it and think of the other applications for this. You could cram the device into a pendant and sell it to anyone who didn’t want their picture taken. This would only be 100% useful at night since people don’t have to use flash during the day, but the idea can be applied to several different things.

    1. That’s actually a really neat idea. You could attach it to a hat or something so your face is just a glowing white spot. I mean, personally I don’t care that much about my picture being taken, but it would certainly be a fun trolling device.

    1. Europeans in general are pretty touchy about this stuff.

      If you have an accident not only will the fine you and take away to licence, they’ll make you pay for any guardrails, signs etc that you hit.

      They get a bit serious, doing things like even testing if you can actually drive, or are capable of changing a tyre. (Dunno if they still do the maintenance stuff. Probably)

  3. Dear inventor,

    Since you are apparently reachable via these comments, please let me express my disbelief that this actually works. Being a scientist, I noticed that some of the facts you’re providing are strage.

    First of all, the physics – you’d have to process the flash, understand it’s nature and only then fire our own. It all has to be done before traffic camera shutter closes. Which happens in under couple hundreds of microseconds.

    This brings me to my second point. All your demos are taken with camera settings that are bound to overexpose the picture. Exposure of 1/60s or 1/80s with a wide open aperture + a flash. They are overexposed even without your device already. Please show us some pictures (originals) of shorter exposure times!

    Finally, it is a bit strange to see that your OverExposed.jpeg picture has been redacted and is not in fact a JPG at all, but a PNG (whereas Original.jpg is a normal pic).

    You might have a working lab prototype, but it won’t scale to real world applications just yet. Please prove me wrong.

    1. I don’t know anything about the specific types of cameras used in red-light cameras, but posts above suggest that they are standard DSLR type sensors in custom housings. What makes you think that they have shutter speeds of 1/10,000th of a second? Most DSLR can not keep the shutter open fully while exposing the image for that short of a time, which would be required with if they use a flash without high-speed-sync.

      As for how to get a flash to fire when it detects another flash, without having it waste it’s power when the shutter is closing, they sell small photo-diode based flash triggers for about $10. Again, as long as high-speed-sync is not involved, the first flash triggers the second/third/whatever and all discharge their light before the shutter closes. Without HSS, shutter speeds are usually locked at about 1/250 to 1/500 at their fastest.

      Lastly, shutter time below the sync speed of the shutter and flash does not affect the intensity of light from a strobe source. I’m a photographer, that’s a lesson learned from practice and Strobist. Sync speed is defined as the speed at which the shutter is fully open for some period of time (again, ignoring HSS tech). The only setting on a camera that affects strobe intensity is the aperture. Given the distance from the redlight camera and flash to the target, and the inverse-square falloff of light, they probably need a near wide open aperture to capture the image. Maybe not 1.0 or 2.8 wide open, but 4 should give enough depth to capture the car at any of the spots it would be at while not filtering the light too badly. There is no reason for the camera to be set at 11 or 16 or more.

      1. Sorry, I must have missed a part of explanation about traffic camera shutter speeds.
        If you take a photo of a car driving at 60mph with a exposure length of 1/80s the car moves 30 centimeters during this time. The line width of symbols of the number plate is just a couple of centimeters. So you have to have a shutter speed way belove a millisecond to actually not blur the license plate and have it still legible and acceptable as evidence.

      2. @Kirils reply
        Milliseconds I can believe; microseconds I was having trouble with. 1/10,000 shutter speed, 100 us, was just a tad too fast. 1/1000 will stop a cars movement pretty well, and 1/5000 even better; but neither will affect the light from a high-sync-speed flash.

        Photo note: below a cameras sync speed, the flash is triggered when the shutter is fully open. Either just as it hits open, or just before it starts to close (front or rear curtain sync). A photo strobe can dump all its light in a few microseconds, so the camera gives it that time. At speeds above sync, 1/250 to 1/500 s in most DSLRs I’ve seen, the shutter is never fully open. So, the flash lights before the shutter starts, and turns off when it closes. The shutter takes more than 1/1000 or what ever to move from open to close, but each part of the sensor/film only sees 1/1000s of light. Using a non HSS strobe with a HSS camera on high shutter speeds results in just a small bar covering some portion of the image, not the full pic as the demo posted shows.

        And I wasn’t arguing that higher speed was needed for proof, just that it would not change the light seen by the camera.

    2. Reacting to the flash in time isn’t that hard to believe.

      Put on one of those auto-darkening welding helmets, and take a photo of yourself. It’ll react fast enough to block the camera flash.

      1. And the sensor is a solar panel.

        As far as circuitry goes, welding helmets are even dumber than those solar garden lights. Some do have rechargeable batteries though.

        That said, this ‘hack’ won’t work, even if it does work ‘as advertised’. Almost all areas have laws against it – the ‘fire a strobe light’ is an old, old, old idea, and you can be ID’d in other ways.

        Motorcyclists who notice the cameras only take photos from the front (very common) and think ‘ah ha, my plate is on the back!’ quickly find ‘the man’ on their doorstop. This is also why you occasionally hear cries from people wanting front plates on bikes.

  4. N.I.T. high dynamic range sensors would definitely still capture it without being anywhere near overexposure.

    I’ve seen them in action where an image was taken of a license plate with a 1kW construction light directly next to it shining onto the NIT sensor. The plate was humanly readable and even the filament in the light could be seen.

  5. What the op is doing is against the law in 47 states and if you get caught doing it you could lose your license for up to six months. So go ahead give this a try and when you get a ticket and have to go to court for tampering with a state issued security device, make sure to remember I told you so.

  6. i find it interesting this ‘prototype’ is only getting demo’ed in a lawn chair. if the creator is so confident of his own work, why is this not already on his own car?

  7. With crosswalk signals counting down seconds in our town it is even more possible to stay out of trouble. Most important it is possible to protest the hurry-hurry world we live in, and slow down deliberately to screw with people that are in a hurry. Being in a hurry is the biggest problem with traffic in the whole world. No clock in vehicle in sight should be required by law! Put tape over it. It irks me when the radio freq is overridden with this dangerous bit of information. If you are in a hurry have the appropriate flashing lights on your car (med or LEO)!

  8. High gloss clear urethane or lacquer spray paint. Apply a few coats to your clean plates and let dry before applying the registration stickers.

    Doesn’t obscure the visual but can cause camera flashes to glare.

    Find a way to mount your plates so the face of them is slightly angled downward. That may make it harder to see the numbers in photos or video when the camera is mounted up high. Would certainly reduce the flash return from high mounted cameras.

    Combined with the clear paint coating it may also cut the reception range of IR laser speed guns.

    Cops aim their lasers at license plates because their retroreflective coating bounces most of the light directly back at its source. A glossy clear coating on a downward angled plate might bounce some of the IR laser down at the road.

    It would be interesting to test.

  9. For sheer amusement, I had a look at the regulations for display of licence plates in various countries.

    The UK site was the easiest to read, and this device appears to break their legislation in at least three ways.

    First up, the plate must be lit so it’s visible at a certain distance. Firing a strobe makes that a bit tricky. Strike 1. (You may be able to argue that one.)

    Secondly, you’re not allowed to make the letters shiny, i.e. contrast between plate & letters must be maintained. Strike 2.

    Thirdly, it bluntly says if you make it hard to photograph, then you’re being naughty. Strike 3.


    I assume every other place on the planet has similar laws.

    Ah well, so much for a legit product. He’ll just scam your money and run away instead.

  10. Just gotta LOL at the workbench:

    I’ve got better gear than that, and I’m a programmer. And I’ve got a real Hakko iron, not a knock-off. I don’t have a frequency meter though, so I guess you win.

    “Our team includes electrical and mechanical engineering professionals that are one of the few Apple certified manufacturers in the United States, a prestigious designation that ensures the utmost expertise and highest quality.” Ha ha, what does that even mean?

  11. I find this hilarious.

    About 3 years ago a guy I lived with actually showed up with one of these things..
    His story was that he had a acquaintance that had developed this thing, and that the guy had found out that he couldn’t patent it because it was counter-productive to photoradar, etc. so had only created prototypes of it and walked away from the final project. It did work, was plastic injected moulded, money was certianly spent on it.

    Got me thinking about a year later how I wanted one. I picked up a pic and some sensors, and had a few strobe lights hanging around, and started to work on it.
    I found a lot of problems, one of which was time and money, and I didn’t have good enough equipment (such as a oscilloscope) to get the timing just right, and that it varied way too much to get a standard “this flash will cancel out all of the plate all of the time”.
    I also tried filtering to stop things like flashlights and natural light from triggering it, but I ran into an issue that I didn’t have the time and equipment to figure out, which was if you get pulled over, and you have a cop with strobe lights on behind you, this thing is going to go off over and over and over in his face. Chances are, it will never be legal because of the light flashing at drivers. If its not legal (not that I care) then you have to hide it from those people who’s job it is to enforce the laws (however bullshit they are). I would be concerned with getting caught with this by a cop..

  12. Won’t work here. We have the redflex system on several of our lights and they all do one very simple thing that would make this not work. VIDEO.

    Every triggering of the system gets reviewed by the police department, and a citation is mailed only if they determine that there is clear intent to run the light. To aid this, they use video footage. The way they have it set up, the video feed is constant, and for each trigger of the system, they save from 10 seconds prior to 15 seconds after the trigger, IIRC. Incidentally, the number of red-lights being run has gone down. Yes, we have short yellow lights, but if you are driving the ridiculous 25mph speed limit, instead of the 35 that most actually drive, you can stop no problem. We also were the city to get the first setup of the redflex collision avoidance system. It’s not at an intersection that would have a high number of colllisions, but it does work. It uses the cameras to see if someone is likely to run the light, and if so, it holds the crossing light at red for an additional period of time, to give the intersection a chance to clear.

    I don’t want this to be construed as me supporting the cameras, as I don’t. However, in my city, they have helped, and with the police reviewing each event, there is the human factor in determining who should get a citation. In the event you get a citation resulting from the system, you can go to the police department and they will have someone come out to the computer they have set up in the lobby explicitly for reviewing the redflex footage, and you can review the footage together.

    tl;dr — This hack won’t work in my city; I don’t like redflex; I think my city does it the right way.

  13. Additional element:

    I’ve seen it all (in three different countries) and will readily agree that both Red Light and Speeding Cams are nothing more than a revenue grab.

    I also approach it from a different perspective-I ride a motorcycle almost full time, and consider “cage drivers” as a personal threat.

    Getting hit and/or run over by a ton of steel will ruin your whole day, and I find that the zones in and around these cams to be the most hazardous part of my commute-largely due to the cams.

    At least some of them I need not worry about-bikes don’t have plates on the front of them-teehee!

  14. I’m days late, but having some apparently rare first-hand experience with redlight cams… In NC (USA), the citations are not like police-issued tickets but are civil fines. In my locality, the proceeds were being split so that some 40% was going to the corporation that installed and maintained the cameras “for free.” The first appeal was to the contractor’s rep, sometimes a retired LEO. After that, you had to take it to small claims court and escalate from there. There’s also a state law that directs 95% of traffic fines be turned over to the school system (intended to keep speed-trap drive-through towns to a minimum). A judge eventually ruled that localities had to heed that law. Cams were removed because the city couldn’t afford to donate 95% of the proceeds to the schools while only receiving 60% itself.

    In practice, the cams caused panic braking. Complaints were so rampant that the city lengthened the yellows from less than 3 seconds to 4 seconds. Then they discovered that lengthening the yellows reduced collisions, regardless of the cams’ presence.

    I received 2 automated tickets. The 2nd was because I tried to avoid getting it. I had no ABS, and nailed the brakes when the light turned yellow. Since it slowed me enough to miss entering the intersection until red and my nose extended into the intersection when stopped, they denied the appeal even though not only the skid marks but the smoke from the tires was clearly visible in the photo.

    The flash-triggered strobe might have worked on our cams, but it probably would have been triggered many times every day by every nearby school bus sporting a strobe, and those are a lot more common than emergency vehicles with lights flashing.

  15. I’ve experimented with filters, coatings, passive polarization, active polarization, angled mountings and some truly silly methods but I hadn’t thought of causing an over exposure! Kudos to you for your efforts and the impressive demo.

  16. The interesting thing is that at least where I live, it is legal to cross an intersection as long as you start to cross while the light is yellow, and yet they still have these cameras and people who don’t know this end up blindly paying the fine because they don’t know. It seems to me that (as previously mentioned) the whole thing is a money grab, and actually is used to prosecute those who are technically in the right.(I believe this applies to the whole US, but I am not sure)

  17. Long Beach, CA

    Just had the original 24 yo plates on my 5.7 TransAm
    “seized for evidence.” The officer insisted they had been “altered with a reflective coating.” She unscrewed them herself.

    They had never been treated.

    AAA said it was their third case that week.

    Studies have shown the coatings do not work.

    To get new plates I need renewed registration.
    To renew registration I need a smog check.
    To pass smog I need a new catalytic converter….California requires a special type and bans most that are legal in the other 49 states.

    I enjoy riding the bus.

    If I had a job this woulf be shere hell… since I don’t… it is very amuzing.

  18. BTW the city of Long Beach has decreased traffic collisions at stop lights intersections by increasing the Mutual Red Time from 0.2 to 0.3 seconds.

    Many cities have license plate scanners mounted in there vehicles. Scans of up to 10,000 plates an hour are fed to a mutual data base.

    Look up … ‘How the Wall Street Journal Obtained the License Plate Data.’

    Malcom (in the middle of the bus)

      1. i work for 3m which recently purchased our alpr company there is a chemical compound you can apply to your plate that will white out the plate read but the systems we build also have a color cam feature (still ir ) im pretty sure with all the new developments at our company that alpr is about to get all the more invasive (facial recognition on interstates for “data collection” and barcoded plates and rfid implants in the plate itself as well ..

  19. I see MOST of the discussion here focused on legality of this and validity of red-light cameras.

    I’m much more interested in the nicely set detection sensitivity and reaction time in a homebrew hack. I think a of a hack like this as just another “proof of concept” type projects that can (and likely will) be applied to other projects.

    Imagine if the light sensor to “noPhoto” reaction was replaced by a carbon monoxide (CO) detector and an car’s interior exhaust fan. Individual spike/surge protectors integrated in appliances, a pressure-sensing home alarm that distinguishes between opening a door and busting it in (where the former waits for a deactivation code and the latter sends an alarm immediately), etc.

    Why know somebody’s hack because it could be used to break a law? Many of the hacks I see can be useful for law-breaking (oxy-acetylene potato gun?) but they can also be used for fun, games, or components in a larger overall utility.

  20. Let the cops get out and “earn” their tickets by getting rid of the traffic-light-ATMs.
    What do they do when the cameras are installed?
    It’s NOT like they go fight crime.
    No… they get positioned elsewhere to write tickets.
    The cameras make things safer you say?? That’s a load of crap!

    I’m not a vandalous type of person but these damn cameras need a bounty on their heads!
    Every camera chopped,lopped or bulldozed down should get $500 reward.

    “F” the cameras and the lazy “traffic taxing” bastards that install them.

  21. Need a hi power,focused radar jammer to trip these things all day long.

    People have to double-check all tickets back at the vendor headquarters before tickets go to local police dept’s for processing.

    Find a way to send RF in a high power focused way and turn these snapshot cameras into nonstop videos.

    Screw those rat bastards.

  22. “The president, chief financial officer and top lawyer for Chicago’s red light camera company resigned this week amid an escalating corruption scandal that has cost Redflex Traffic Systems Inc. its lucrative, decadelong relationship with the city. … The Chicago program, with more than 380 cameras, has been the company’s largest in North America and is worth about 13 percent of worldwide revenue for Redflex Holdings. Since 2003 it has generated about $100 million for Redflex and more than $300 million in ticket revenue for the city.”

  23. Just an aside, if you get ‘caught’ in the middle of an intersection when the light goes red, you should never have driven into it in the first place. Not only is keeping the ‘box’ clear a law in most places, it is just a nice, considerate thing to do anyway as cars stuck in the intersection block the cars that now have the green. Be thoughtful, and have a nice day :-)

  24. the biggest problem with these types of tricks is most red light cameras have been upgraded or replaced to use video in addition to two photos, you’re not going to fool a video camera in the day time, it will have many usable frames from the video even if there was a flash obscuring a few.

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