Safe Speed Forums

This one is easy, and the technology simple and years old!
NASA wished to photograph the rocket exhaust in a early ATLAS rocket, AND view the control surfaces to correlate the effects produced.
A slow 32 ASA film rating showed the flame clearly, but was toodark to see the surfaces.
200 ASA rating film showed the control surfaces, and captured the movement of the rocket, but the exhaust flame "burned out" on the film.
They simply sandwhiched three emulsions, of differeing speeds, which could be developed as coloured layers, which could be printed using corresponding filters to show highlight detail, AND shadow detail all in one exposure through one lens.
With video, a beam splitter sent the image to three vidicon tubes, of three sensitivities, achieving the same result.
Now with micro chip arrays, AND software, viewing a numberplate between two exceedingly bright light sources is no problem at all.

You no longer need an aperture to control brightness, as an electronic aperture will achieve the same result. However an aperture is still desirable because of it's effects on focusing and depth of field.

Infra red is like visible light, in that it comes in a range of frequencies.
Those nearer to visible light will record similar information from numberplate materials as visble light, so it will "see" and record changes in "brightness, as visible light does.
To fool an infra red camera, a numberplate would have to have light and dark materials (in visible light) with IDENTICAL infra red reflective/absorption properties at the frequency being employed in the detection system.

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Time to take responsibility for our actions.. and don't be afraid of speaking out!

If you mean ‘can SPECS cameras be overloaded?’ I would say yes. The SPECS cameras use CCD imagers (CMOS is less sensitive due to the relatively small active area). The data from CCD imagers are usually read from the array in a serial manner, overloading of some of these pixels can lead to ‘blooming’ of the entire row (or column) of pixels, hence effectively smearing the resultant image. A quick Google yields:

http://www.e-z.net/~haworth/ccd/blooming.html

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Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign

Smeggie - a technical idea - since optical electronics is not my field, merely a side issue - nice thought though - how to put specs out of the picture - thought the SCP would soon have cars out looking for the culprits to make more money


However , a paintball gun would be a good substitute

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lets bring sanity back to speed limits.
Drivers are like donkeys -they respond best to a carrot, not a stick .Road safety experts are like Asses - best kept covered up ,or sat on

SPECs may be able to see you in the dark but you may not see them in the dark. We've had several SPECs enforced stretches on the M2 lately along roadworks 50mph limit. They are painted yellow but for some reason its not reflective paint. In the dark they are invisible until a few yards away.