Discussion
What chance do I stand of getting done by one of these at 10 MPH over the posted limit? (50 in a 40). They are digital aren't they? If that's the case they will get everyone who goes past above the limit, unlike gatso's which may be out of film or be a dummy one?
Anyone know how far in front they measure your speed? I was on the brakes sharpish but it may have already got me!
So annoyed with myself, with one pending I may end up with 9 points on my license. I really hate these bloody things, hardly public enemy number 1 doing 9-10 mph over!
Wouldn't mind if was near a kiddies playground or something, but it's on a huge expanse of road that leads out to the main Nottingham ringroad! (Near Harry Ramsden's / BBQ Warehouse for anyone local.)
Got a nervous couple of weeks coming up!
speedeight said:
What chance do I stand of getting done by one of these at 10 MPH over the posted limit? (50 in a 40).
Anyone know how far in front they measure your speed? I was on the brakes sharpish but it may have already got me!
The enforcement threshold would probably be set lower than 50 in a 40 limit...Anyone know how far in front they measure your speed? I was on the brakes sharpish but it may have already got me!
On the plus side, Truvelo cameras (you are sure it was a Truvelo ?) use piezo sensors embedded in the road surface. If these sensors detect a vehicle exceeding the enforcement threshold, the internal electronics predict how long until the front wheels will straddle the white lines painted on the road surface just short of the camera (typically within 20 feet). A single photo is then taken after this predicted time delay. If the photo shows the wheels astride the lines, then this provides the corroborative evidence of excess speed. As long as you anchored on before you reached these white lines, then you should be OK..
Edited by SS2. on Monday 7th August 16:15
SS2. said:
speedeight said:
What chance do I stand of getting done by one of these at 10 MPH over the posted limit? (50 in a 40).
Anyone know how far in front they measure your speed? I was on the brakes sharpish but it may have already got me!
The enforcement threshold would probably be set lower than 50 in a 40 limit...Anyone know how far in front they measure your speed? I was on the brakes sharpish but it may have already got me!
On the plus side, Truvelo cameras (you are sure it was a Truvelo ?) use piezo sensors embedded in the road surface. If these sensors detect a vehicle exceeding the enforcement threshold, the internal electronics predict how long until the front wheels will straddle the white lines painted on the road surface just short of the camera (typically within 20 feet). A single photo is then taken after this predicted time delay. If the photo shows the wheels astride the lines, then this provides the corroborative evidence of excess speed. As long as you anchored on before you reached these white lines, then you should be OK..
Edited by SS2. on Monday 7th August 16:15
Thanks for the info. It was definitely a Truvelo yes.
Fingers crossed!
speedeight said:
Thanks for the info. It was definitely a Truvelo yes.
Fingers crossed!
Seconded. My Indago flags it up as a Truvelo. Funnily enough I never have any problems with the one leaving the city but have had a few close calls with the one on the opposite side of the carriageway.
Can’t disagree with SS2 
However, you would have to scrub off 20% of your speed in the 1-2 meters between the sensors and the white lines 
No, they use wet film (like gatsos), which run out (like gatsos), so you might get lucky.
Did you see an obvious magenta flash as you got close to it? If not then you’re OK anyway.
However, you would have to scrub off 20% of your speed in the 1-2 meters between the sensors and the white lines speedeight said:
What chance do I stand of getting done by one of these at 10 MPH over the posted limit? (50 in a 40). They are digital aren't they?
No, they use wet film (like gatsos), which run out (like gatsos), so you might get lucky.
Did you see an obvious magenta flash as you got close to it? If not then you’re OK anyway.
smeggy said:
Can’t disagree with SS2 However, you would have to scrub off 20% of your speed in the 1-2 meters between the sensors and the white lines
No, they use wet film (like gatsos), which run out (like gatsos), so you might get lucky.
Did you see an obvious magenta flash as you got close to it? If not then you’re OK anyway.
However, you would have to scrub off 20% of your speed in the 1-2 meters between the sensors and the white lines speedeight said:
What chance do I stand of getting done by one of these at 10 MPH over the posted limit? (50 in a 40). They are digital aren't they?
No, they use wet film (like gatsos), which run out (like gatsos), so you might get lucky.
Did you see an obvious magenta flash as you got close to it? If not then you’re OK anyway.
No, I didn't see any flash. I thought they used infra-red flash so they don't blind oncoming drivers? Is there a magenta visible tint to this then? If so, I didn't see it! I hope that's a good omen
speedeight said:
No, I didn't see any flash. I thought they used infra-red flash so they don't blind oncoming drivers? Is there a magenta visible tint to this then? If so, I didn't see it! I hope that's a good omen
IR flash is a myth.
In fact I saw the Truvelo at the entrance to the M275 flash Saturday evening. I spiritedly accelerated away from a set of lights (I certainly didn't floor it, wasn't racing anyone and was within the limit - for a good reason). Some t**t in another lane thought it was 'game on' so he put his foot down and kept up (but I wasn't even trying
) but he just kept on accelerating over the limit. AFter he passed me I gave him some main beam to warn him of his impending mishap - to no avail..... FLASH!
Then he slowed down
(it's amazing just how many slow after being flashed). I put my foot down as I passed the 3 lines and off I went
cooperman said:
Just a part of the cash-collection obsession.
You might just ignore the HiP if it arrives, then ignore all other correspondence and wait for the arrest warrant. It may never come.
You might just ignore the HiP if it arrives, then ignore all other correspondence and wait for the arrest warrant. It may never come.
My girlfriend did exactly this with her last one. That was 8 months ago and nothing happened. Must be worth a shot....
Cross your fingers speedeight, I can almost see that truvelo from my window here. Odd thing is the dangeroujs bit is (the crossroads near Wickes,) nowhere near the cameras (one either side of the road).
If you hit the anchors hard enough then you might be ok.
Can't say the new ringroad speed limit is much fun either!
If you hit the anchors hard enough then you might be ok.
Can't say the new ringroad speed limit is much fun either!
The sensor pads for the Truvelo are so close to the camera that you stand a good chance of slowing in time.
And it definately is a noticable magenta flash, I have heard it was IR, but I saw one go off the other week (on the Isle of Wight, they love 'em down there!) and you definately notice. Kind of makes you wonder why they bother making it magenta it's so bright!
And it definately is a noticable magenta flash, I have heard it was IR, but I saw one go off the other week (on the Isle of Wight, they love 'em down there!) and you definately notice. Kind of makes you wonder why they bother making it magenta it's so bright!
shuvitupya said:
There are 2 sets of sensors, which can be as much as 20 metres apart, so if you go too fast over the first set brake hard or even stop!
Nope!
The two pairs of sensors are very close to each other (I suspect they actually overlap: 1a 2a 1b 2b); the sensors are close to the corroborating white lines (1.8 meters from the last sensor) - there's no way you could stop or scrub off enough speed in that short distance.
Andrew D said:
And it definately is a noticable magenta flash, I have heard it was IR, but I saw one go off the other week (on the Isle of Wight, they love 'em down there!) and you definately notice. Kind of makes you wonder why they bother making it magenta it's so bright!
The low-frequency cut-off point in the human range of optical sensitivity varies from person to person. What is invisible near-IR to one person may be visible red to another. Me, I can't see IR LEDs, but I can see a Truvelo flash, though it's pretty dim.
smeggy said:
No, they use wet film (like gatsos), which run out (like gatsos), so you might get lucky.
I thought the whole IR thing was due to them using digital photography - the sensitivity of a silicon photodetector peaks in the near IR - with the supposedly non-dazzling flash as a side benefit.
Pigeon said:
smeggy said:
No, they use wet film (like gatsos), which run out (like gatsos), so you might get lucky.
I thought the whole IR thing was due to them using digital photography - the sensitivity of a silicon photodetector peaks in the near IR - with the supposedly non-dazzling flash as a side benefit.
You are right about typical digital imager spectral sensitivity, but:
truvelouk.com said:
Single photo per offence doubles capture rate per film. (and halves film & processing costs).
Truvelos use film.
Film has a poor IR response, flash strobes have poor IR output.
smeggy said:
shuvitupya said:
There are 2 sets of sensors, which can be as much as 20 metres apart, so if you go too fast over the first set brake hard or even stop!
Nope!
The two pairs of sensors are very close to each other (I suspect they actually overlap: 1a 2a 1b 2b); the sensors are close to the corroborating white lines (1.8 meters from the last sensor) - there's no way you could stop or scrub off enough speed in that short distance.
Well, the new ones on the A452 have sensors at least 20m apart, so what is that all about?
shuvitupya said:
Well, the new ones on the A452 have sensors at least 20m apart, so what is that all about?
As your good self already highlighted: that would be a dumb thing to do, especially as there’s no need for them to be so far apart.
I would have to see evidence before I can accept that info. Could you get a photo of that setup?
smeggy said:
shuvitupya said:
Well, the new ones on the A452 have sensors at least 20m apart, so what is that all about?
As your good self already highlighted: that would be a dumb thing to do, especially as there’s no need for them to be so far apart.
I would have to see evidence before I can accept that info. Could you get a photo of that setup?
Another reason why I don't and won't believe the sensors are 'at least 20m apart':
It would be possible for one car to drive over the first two strips then brake to a stop and at the same time a second car to accelerate from stationary to the trip threshold as it crosses the second sensor pair and the corroboration lines – resulting with a irrefutable but false conviction
Perhaps what you saw was a form of MIDAS sensor? (separate from the camera system)
smeggy said:
smeggy said:
shuvitupya said:
Well, the new ones on the A452 have sensors at least 20m apart, so what is that all about?
As your good self already highlighted: that would be a dumb thing to do, especially as there’s no need for them to be so far apart.
I would have to see evidence before I can accept that info. Could you get a photo of that setup?
Another reason why I don't and won't believe the sensors are 'at least 20m apart':
It would be possible for one car to drive over the first two strips then brake to a stop and at the same time a second car to accelerate from stationary to the trip threshold as it crosses the second sensor pair and the corroboration lines – resulting with a irrefutable but false conviction
Perhaps what you saw was a form of MIDAS sensor? (separate from the camera system)
I will try to get a picture, and yes I thought it strange that there is a long way between the sensors for the reasons you give.
Edited by shuvitupya on Tuesday 8th August 22:32
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