Traffic Light Cameras - do they measure speed?

[oldhatter]

Hi
Last Saturday night I was driving down the A6 and turning left at lights onto another A road. At that point there are two lanes in "my" direction and I am in the left lane signalling left. Reasonably, another car going straight on takes the right lane and overtakes as I am turning left. It was quite foggy and dark (8pm) though I doubt either fact is relevant. Lights are clearly green for both of us throughout the period in question. I am going slowly as I turn left (10-15mph I guess)the other guy somewhat faster. As we go through the traffic light camera flashes several times. Is it possible for these to now measure speed, or was there a fault in the set up?
Steve
ps did a quick search and couldn't find answer - apologies if it was staring me in the face!

[filmidget]

Some sites are set up for speed and red light violations.

[pdV6]

The Monitron cameras can be set up to enforce traffic signals and/or speed limits.

[oldhatter]

Thanks for that - I had always assumed they were only set up for one or other.
Steve

[goochie]

So if the "traffic light cameras" can catch speeders too, why are conventional GATSO's in much larger boxes?

I would be amazed if the induction loop in the traffic light cameras' system (in the road) woul dbe accurate enough considering how close together the cables are and the effect of different vehicle sizes etc. on its accuracy.

Induction loops are fine for traffic light jumpers but speed?

[pdV6]

Monitron cameras are in widespread use in both speed and/or signal enforcement.

In fact, around here a lot of GATSOs are being replaced with Monitrons.

[Athey997S]

99% are dual purpose mate!

[goochie]

So why are gatso cameras so big if a smaller, more discreet device can do the same job?

[pdV6]

goochie said:

So why are gatso cameras so big if a smaller, more discreet device can do the same job?

GATSO units incorporate a RADAR plus analogue camera and flash unit, including the film cartridge.

The newer Monitron ones are digital rather than film-based and work using inducive loops in the road.

As to the relative size, there is always a large equipment box near a Monitron whereas a GATSO is pretty much self-contained, so you could argue that the Monitron system is actually larger overall.

[flemke]

goochie said:

Induction loops are fine for traffic light jumpers but speed?

Truvelo

[Flat in Fifth]

And what is the secondary corroboration evidence in the case of Monitron?

We know it's the white lines with Gatsos, in theory there is that with Truvelo, but it is arguable that it is very difficult to check from the photos.

Monitron? I've never seen a white line near one. OK there are loops in the road and in theory one might be able to make measurements during a site visit.

[sjtscott]

Flat in Fifth said:

And what is the secondary corroboration evidence in the case of Monitron?

We know it's the white lines with Gatsos, in theory there is that with Truvelo, but it is arguable that it is very difficult to check from the photos.

Monitron? I've never seen a white line near one. OK there are loops in the road and in theory one might be able to make measurements during a site visit.

White lines deployed for all the ones I've seen in London. Some in the centre of the lane some either side of the lane.

[splodge s4]

Is it still the case (definately) that Gatso & Monitron flash your rear & Truvelo from the front?

[Flat in Fifth]

sjtscott said:

Flat in Fifth said:

And what is the secondary corroboration evidence in the case of Monitron?

We know it's the white lines with Gatsos, in theory there is that with Truvelo, but it is arguable that it is very difficult to check from the photos.

Monitron? I've never seen a white line near one. OK there are loops in the road and in theory one might be able to make measurements during a site visit.

White lines deployed for all the ones I've seen in London. Some in the centre of the lane some either side of the lane.

Ah thanks for that, must be an area thing no lines on Moronitrons round here.

Answer to splodge, beware the T36 Gatso, can be used in both directions, but it is a loop sensor device rather than a radar, and it still needs white lines in theory. Des not stop one set of scamps using it in front facing mode without lines though. Why? It cannot, in theory at least, hold up in court, so all it can do is cause danger by flashing in people's eyes.

[pdV6]

Some don't have "traditional" lines but rather a series of white dots that are much harder to spot. (see what I did there?)

[mechsympathy]

pdV6 said:

In fact, around here a lot of GATSOs are being replaced with Monitrons.

Probably because it's much harder to hang a tyre full of unleaded on a monitron

GAH! Spooling

Edited by mechsympathy on Friday 9th February 12:07

[who me ?]

splodge s4 said:

Is it still the case (definately) that Gatso & Monitron flash your rear & Truvelo from the front?

Apparently Truvello can work either way ,and i've seen it, but in reverse they seem to use the gatso style lines.
As for road markings for Monitron - ones on Kenton road ,opposite (ish) Nash way have gatso style markings.

[bluepolarbear]

Flat in Fifth said:

We know it's the white lines with Gatsos, in theory there is that with Truvelo, but it is arguable that it is very difficult to check from the photos.

The white lines on truvelo provide much better accurancy for secondary evidence. On Gatso while the interval between flashes needs to be known it doesn't matter what it is. This leads to the possibility that the programmed interval isn't the actual time therefore creating errors in the evidence. Because of the fix nature of the measuring points in Truvelo the timing has to be specific. If it drifts the seconday evidence will always visable show that error and prevent the charge being made.