Safety camera today

cyber69

cyber69

cyber69

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I drove over the brow of a hill on my travels today and noticed a speed camera right at the very bottom of the road.

Does the van take 3 readings over a certain distance normally? He's quite some distance away and as I came over the brow of the hill I was doing a couple of mph over 30 for about 3 seconds.

Van is circled in red!

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Do you think the laser is pointed towards the very brow of the hill or a bit further down? It was a very good spot to put the camera van, you couldn't see anything until you came over the top.
 
It's partly why I got a car camera in the first place. Even though I go past these vans at a 'safe' speed I then question myself later!
 
I think you need to be a lot closer than that for them to get a reading.

It's either radar or laser, so there needs to be a clear signal bounced off a flat surface on car. The further away you are, the harder it is. If you mount your number plate tilted slightly, it makes it really hard to get a reading on some cars. Even harder if you wrap it in matt black :D
 
Kenai said:
They work well over a km and are typically used up to around a km I thought? That certainly looks plenty close enough for it to work ok.
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I think that is the average speed cameras on motorways, but they work by reading the number plate.
 
Nasher said:
I think you need to be a lot closer than that for them to get a reading.

It's either radar or laser, so there needs to be a clear signal bounced off a flat surface on car. The further away you are, the harder it is. If you mount your number plate tilted slightly, it makes it really hard to get a reading on some cars. Even harder if you wrap it in matt black :D
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The UK does not use Radar for this application any more. As far as I am aware LIDAR is universally used for handheld and mobile applications. You do not even need to use the numberplate to get a reading, it does NOT need to be a perfectly flat surface and tilting your numberplate it is not going to make any discernible difference. It needs to be a surface of the vehicle that permits a reflection, modern devices are very strict about what they will accept as valid readings. If they detect slip or other erroneous states they will not display a speed reading, only an error.

How do you think readings are taken from motorcyclists? You can get readings from matt paint, granite walls, painted walls, joggers, cyclists, flying birds. Highly reflective surfaces just make it quicker to pull a reading.

The OP is approx 226M away from that mobile camera. This is an easy ping on full standing handheld. It is an instant reading for an operator with a van/tripod mounted device with it already zeroed in on the section of road pictured. Which is entirely straight with excellent line of sight and visibility. If you get pinged there going past a load of schools then you deserve it :p

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snapdragon69 said:
On youtube examples, I would say they are as quick as an autofocus on an SLR.
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Yes, that's also a good analogy. AutoFocus is rapid with a steady hold, good lighting/conditions and little noise to interfere. It's slow and sometimes takes a few tries to focus if you are not careful or conditions are poor. Exactly the same as LIDAR speed devices.

The device can be operated in single shot mode which records and displays a single speed for each trigger pull and hold, release and pull again for further readings. With a skilled operator it's quick enough to take rapid successive readings, easily 1 per second.

They can also be operated in continuous mode which gives a continuous speed reading with a trigger pull and hold, let go to commit readings. Very effective with tripod/mounted devices. This mode can also be configured with a trigger speed. Such that a continuous reading is taken until the trigger speed is reached, it will then commit and display the readings recorded.

Even if the reading is not on the display/cleared/whatever else.The device stores readings taken to internal memory which can be polled. All of the manuals are available online if you care to read them!
 
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Nasher said:
I think that is the average speed cameras on motorways, but they work by reading the number plate.
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Looking it up, it seems it depends if it was laser or radar;

How does a laser gun work?

Laser handheld speed camera guns use a narrow beam of light about 10cm wide. This laser beam bounces from the target vehicle and provides the police officer with a speed reading. The speed is displayed within 0.5 seconds of use meaning speed camera detectors do not have long to warn you that laser is in use. The range of laser guns is about 1 mile.

How does a radar gun work?

Radar handheld devices use radio waves to target a vehicle. As a vehicle passes the radio waves these are reflected back at the radar receiver allowing the handheld radar gun to work out how fast the vehicle is traveling. The speed reading takes no less than 3 seconds for the police officer to acquire. The range of these systems is about 300 yards.
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Either way, i'd say there is a good chance that camera was in range, hence putting himself there to catch people before they spot him having come over the crest.
 
The device being used in that van will be LIDAR, guaranteed. I would suggest the certified operating distances for the device to be between 20 and 600 metres. The OP still would have needed to have been over double the distance away to fall foul of certification.

OP, post the entire video clip? :p

As a point of note - Average Speed Cameras are an entirely different technology. They use ANPR and perform basic 'after the event' distance over time calculations to work out speed. They do not perform ANY direct speed measurements. You could enter an average speed zone at double the speed limit, have a coffee and a pee in a services before the next camera emplacement for a while and then continue on. The calculated speed is a result of your distance over time.
 
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I was doing just over 30 for about 3 seconds after coming over the brow of the hill then slowed back to 30.
 
Then I would not worry, assuming "just over" is 2 or 3 MPH. If not though, the range of the van is not going to help you! Keep us posted over the next 14 days! :D
 
In South Yorkshire they park all sorts of places, the worst I have seen is in a parking bay and the end of a dead straight road with a right hand hill on the side.

Loads of people would've got caught by it. :mad:
 
Girl at work just got a NIP for doing 74 in a 30.
She's been driving the same route for a year and claims she didn't realise the road reduced from NSL to 30.
There's a full size 30 sign followed by a small repeater about 100m later.
About another 100m later there's an LED sign that lights up whenever anyone goes past at above 30.
The police officer was about 200m after that using a handheld.

I was caught on the same stretch about 20 years ago. I was doing 49 and the limit back then was 40. Luckily I was let off with a warning!
 
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