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Speed Cameras

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TheMoonlitKnight

TheMoonlitKnight

Structural
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Is anyone aware of how reliable speed cameras are at distinguishing between the speeding vehicle and the vehicles that just happen to be at the same position and time in an adjacent lane? Or are they capable at all?

It struck me as somebody was passing me going 80 mph in a construction zone and the camera flashed right as I was next to them.
 
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I have thought of this too. I would think that determination of the faster vehicle within the zone could be done by looking at the relative image "blur" of either vehicle. Whether that is or would be done (if at all) by a software algorithm or by I person I couldn't say even though there are quite a few image processing algorithms. If tickets are issued "automatically" both vehicles might get ticketed in hopes that at least one would return a check for the fine. "Guilty by association".

Bruce Youngman
 
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?? The camera must have been triggered by some sort of sensor already, since the camera itself cannot necessarily distinguish absolute speed. The triggering sensor will already know which car it was.

TTFN
faq731-376
7ofakss

Need help writing a question or understanding a reply? forum1529
 
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IRstuff, excellent point. I replied based on the assumption that both vehicles potentially being within the target sensor FOV. Depending upon approach angles, it might not be clearly defined which vehicle is truly being measured.

Bruce Youngman
 
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IR: Your "??" strikes me as you are telling me I am foolish for not knowing the answer. Shame on me, I guess.
 
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Not that you didn't know the "answer," but that you didn't apply some cause and effect. The flashing is obviously there so that the cameras can get good images, so by inference, without the lights, the cameras cannot reliably get good images, hence, there must be another sensor involved, which triggers the camera and lights.

Moreover, it took less than 30 seconds of searching to find the cited link, which begs the question why that search hadn't been done before.

TTFN
faq731-376
7ofakss

Need help writing a question or understanding a reply? forum1529
 
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I apologize for wasting your time and Eng-Tips server space. :)
 
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