The GATSO is the most famous speed camera however other cameras (below) are often mistaken for them.

GATSO's measure vehicle speed using RADAR and/or sensors in the road. The photo a GATSO takes usually requires line markings on the road as a secondary verification of your speed (the RADAR reading being the first).

GATSO's are versatile and can cover two lanes (such as on a dual carriageway), opposing traffic flows (to catch vehicles in both directions e.g. on an A-road) or red light based. GATSO's can work if you're driving toward or away from them.

Red light cameras can also act as a speed camera when the lights are amber or green to catch speeders trying to make a green light as well as catching those running a red light.

Our team of expert lawyers can advise you on the merit of the police's case against you and if you can escape punishment.

TRUVELO camera's look very similar to the GATSO unit but can be identified because they are usually blue in colour and have two lenses on the front and typically face oncoming traffic

Unlike the GATSO, TRUVELO normally use sensors in the road surface to gauge a vehicle's speed. This makes it undetectable by conventional radar/laser detectors.

The fact they use road buried sensors also means they are less mobile than a GATSO unit. They can still perform the same range of tasks as a GATSO camera, but their relocation requires destruction to the road surface and therefore a higher cost to the tax payer.

PEEK can use either sensors in the roads surface or radar. These units were designed to overcome the earlier shortcomings of the GATSO unit...

Originally, a GATSO unit could not take speed readings of traffic driving away from the camera (only toward it). Therefore, many motorbikes would be photographed speeding toward a GATSO unit but would go unidentified as they do not have a forward facing licence plate.

Upgrades to GATSO units have allowed them to take speed readings and photographs of both directions traffic. Due to the higher cost of ripping out a GATSO unit just to replace it with a PEEK unit compared to simply upgrading the GATSO, PEEK Cameras are becoming rare but you can occasionally spot the odd one or two.

Speedcurb cameras are uncommon in the UK. They can simultaneously monitor traffic light and speeding offences. They are rear facing like the DS2 (below) and TRUVELO (above) and exclusively use sensors in the road surface. Therefore RADAR/LIDAR detectors are useless against them.

They are much cheaper to install than SPECS (below) and have a much greater storage capacity for photos than a conventional GATSO, so these are gaining popularity in temporary road work areas where digging up the road surface for the sensors is not a significant inconvenience.

SPECS (Speed Check Services) is an average speed measuring camera system with built in infra-red illuminators and ANPR.

These cameras are not standalone systems - more than one is required. The first camera point takes an image of every vehicle that passes regardless of that vehicles speed, using ANPR it simultaneously checks each licence plate for any active police warrants.

When you pass through the next unit your average speed is calculated. If your average speed is too fast for the road a ticket is automatically issued. Subsequent units continuously monitor your average speed.

The units can be miles apart and may be mounted on a pole, bridge or similar structure all linked together by a computer system known as SVDD (Speed Violation Detection Deterrent).

Because these units are digital they never run out of film. When the camera's memory starts to get full they communicate with the SVDD mainframe and offload all their data.

SPECS doesn't emit a RADAR signal, so radar/laser detectors are again utterly useless.

This device captures speeders using both radar technology and sensors in the road.

Four high resolution digital cameras use infra-red flashes, so speeders don't know they're being snapped. They are allegedly bomb and fire proof. Any vibrations or smoke detected by the system sends an alert to the nearest police station. While this is very clever, is the glass paint proof?

Click the image to get a full idea of these beasts.

The Red Light Cameras are devices linked to the traffic light sequence with sensors in the road surface.

When the lights are red anything passing over the sensor in the road is photographed.

Upgrades are being performed to these devices to have radars fitted, allowing them to capture motorists who speed when trying to make a green light. This means you could be hit with two offences simultaneously: speeding and a red light!

Because these are/were primarily red light cameras upgraded to add speed camera functionality many of them remain looking like red-light only cameras. I.e. they did not paint them yellow/orange as part of the upgrade, meaning many motorists are being caught off guard by these boxes.

Watchman units are both rear facing speed cameras (so can catch motorbikes) and ANPR (Automatic Number Plate Recognition) combined.

They are usually accompanied by a "speed board" (the yellow RADAR zone below) which displays the speed limit for that particular stretch of road along with your current speed. This allows you to slow down before hitting the Watchman RADAR zone (in red below). If you're found to be speeding a photograph will be taken in the trap zone (in white below).

(Photo was found on the motorcyclenews.com web site.)

Regardless of your speed, your number plate will always be read for any active police warrants in the white zone above.

Because your speed is calculated before you pass the main unit the usual "just slow down through the trap zone" trick wont save you.

The data is stored digitally and transmitted wire free meaning unlimited film.

Maybe the DS2 stands for "Difficult 2 Spot"...but apparently it's short for Speedmaster 2! This trap consists of a sensor in the road that calculates your speed as you pass over it.

If you click the image to the left (from speedcam.co.uk) you can see a small grey post in front of the speed camera sign. A camera van plugs into this post and automatically photographs any speeding vehicle that triggers the trap.

This trap is not active when a camera van is not "plugged in" to that post. Yet again, RADAR/LIDAR detectors are useless at alerting you to these.

Currently in development and being tested on certain roads in Devon and Cornwall, satellites in space monitor thousands of cars simultaneously. Any car that is found to be speeding is tracked and using Number Plate Recognition (ANPR) from ground stations a ticket can be issued.

The system is much cheaper to install than the existing SPECS cameras so if the test goes well this could be applied to ALL UK roads.

These are those little CCTV cameras on bridges and at the side of the road on motorways as well as those tall blue stalks on a-roads.

They automatically count the volume of traffic and ESTIMATE the average speed (of ALL the cars - not the average speed of any ONE car) as a whole.

Any slow moving traffic (i.e. traffic jams) can then be mitigated by relaying this message to drivers via those large black display boards on motorways and live traffic info screens in service stations.

These are NOT used directly for speed enforcement, however they are still CCTV cameras monitored by humans who work for the highways agency. If the control room noticed someone driving in a manner that endangered other road users (e.g. excessive speeds) the police are usually alerted to go pick them up.

ANPR (Automatic Number Plate Recognition) reads your number plate by using OCR (optical character recognition) technology on a digital photo.

The digital photo can be from a variety of sources including CCTV Cameras (like those found in petrol garages) to more specific cameras like those listed above. Your licence plate is cross referenced within 1.5 seconds with both the police and DVLA databases for any active warrants. 

A single ANPR camera can check up to 3,000 licence plates per hour. These cameras usually come in clusters of 3 or more, meaning around 9,000 plates per hour can be processed per 'site'.

The limitation of these devices is mainly the speed of the vehicle... vehicles traveling over 100mph usually create an image too blurry for OCR technology...

ANPR cameras are not at present speed cameras, but there are discussions (mid 2011) to centralise all ANPR cameras (petrol stations included) and by applying the SPECS software technology a computer could calculate the minimum average speed between the two points.