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Roadside
Cameras
As you will be aware, a vast network of cameras monitor the driving behaviour of motorists. Most cameras check the vehicle's speed, whilst others watch for vehicles passing through red traffic signals. All in all, there are now over 6,000 cameras dotted across the UK, and are either fixed or mobile. The types of camera in use differ by model, with councils and police authorities choosing to use different types. Cameras can be found on the roadside, in the central reserve, or even on a overhead gantry. This feature explores the different types of cameras that can be found in the UK.
Speed Cameras
The camera works by emitting radar beams to measure a vehicle's speed. If the trigger speed is broken by a speeding motorist, two photographs are taken half-a-second apart. The camera uses a powerful flash to show the rear of the vehicle, the registration plate, and the dotted lines in the road. The cameras themselves are usually rear-facing, to stop the flash from blinding oncoming motorists. However, it is becoming more common for cameras to be used to catch vehicles travelling in both directions, and can also be swivelled to check different sides of the road. They can also distinguish between different vehicles, so if a 40mph limit was imposed on trucks, yet cars could travel at 60mph, the camera can enforce the two separate speed limits.
As mentioned previously, a series of dotted lines are to be found hand-in-hand with Gatso installations. These are calibration markings, and are used to back-up the Gatso's radar readings, as the photographs are the only evidence admissible in court. This is because the speed calculated by the radar is deemed to be too unreliable, as it is prone to error from simultaneous reflections, multiple vehicles etc. By counting how many lines have been passed between the flashes, the speed of the vehicle can be calculated. Also, on the M25 in Surrey and Berkshire, Gatsos have been installed on overhead gantries, so all four lanes on the carriageway can be constantly monitored.
Two pairs of piezo-electric strips are installed into the road prior to the camera, each strip a set distance apart. The time taken for the vehicle to pass between each strip is measured to give its speed, thus the camera only needs to issue a single photograph of the vehicle. If the speed calculated by each pair of strips do not match (+/- 1mph different), the offence is rejected. A series of narrowly-spaced lines are painted on the road in front of the camera to distinguish between the offending vehicle and any innocent vehicles that so happen to be passing at the same time.
Watchman
Generally, they work in the same manner as the Gatso, using radar beams and a flashing bulb for taking the photograph. Again, most are rear-facing due to the brightness of the flash. There are also some of these cameras that have been adapted to be used as red light cameras, used in the same way as the Red Light Gatso, shown below.
SPECS
Semi-Permanent Cameras
DS2 cameras
Mobile Cameras Commonly used to catch motorists on specific roads at certain times, mobile cameras are compact and easy to move around. Generally, there are two types of mobile camera commonly used. First is the Mini-Gatso, similar to its big brother but installed onto a trailer for ease of movement. The other type of mobile camera is the 'laser gun' camera, which uses Number Plate Recognition, and can record speeds and take pictures up to one kilometre away.
Red Light Cameras
Red Light Gatso Whilst only one photograph is required as proof that the offence has taken place, the camera in fact takes a second image to act as confirmation when the film is being examined afterwards. One major change that has been made to these cameras is the installation of a radar beam. This has been carried out in some areas so that they can double up as a speed camera when the traffic signal is on green, changing to a red light camera once the signals have changed.
Dual-Purpose Cameras
The system uses induction loops for red light monitoring and piezo-electric strips when checking vehicle speeds, with the camera having the ability to switch modes when the traffic changes from red to green (if set up to do this).
Congestion Charging Cameras
Penalties and Points At present, any driver prosecuted in the UK following being caught by a speed camera can result in a minimum of three penalty points and a £60 fine. However the fine amount may be increased in the future as it is currently under review by the government. |
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