Safe Speed Forums

Recently visited South Wales, shortly afterwards received a NIP, convinced I would not have been speeding, I wrote a lovely letter which resulted in a response with two photo's taken from a video clip taken at the time. 70 in a 60.

Taken on a deserted road going up the valleys past the Brecons Resovior.

1st Photo shows close up of my number plate, 2nd photo shows long distance shot of my vehicle.

2nd photo text: *-070 mph & 0348.3m

Still convinced I would not have been doing 70 on an A road, I'm looking for help and advice.

I can visit Cardiff to see the Video for myself. (500 mile round trip)

How does video work out the speed
Do they have measured points on the road they work from
Are they laser assisted
Etc

Thanking you in advance

This is a LTI20.20 laser speed meter in a camera van connected to video.

The laser speed meter is dodgy at best, especially with vans. It should have been withdrawn years ago.

Nevetheless it remains hard to fight. In the circumstances you describe it's possible - or even likely - that alternative evidence of speed could be obtained by examining the video. This would be on the basis of finding something in the video of known distance (white lines on the road perhaps) and calculating speed from time (video frame count) and distance (number of white lines and length of lines).

You probably won't be able to get hold of the video for such examination unless you refuse the fixed penalty and plead not guilty.

It's going to be a serious pain, whatever you decide.

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Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

From the photographs it should be possible to make a good estimate of the speed of your car from the two photographs you received, particularly if there was a significant time interval between them. Accurately measure the ratio of the size of the image of your car, relative to the size of the image frame if the photos are of different scales. The ratio of the size of your vehicle image should be about the same ratio of the distance you were from the camera. Given this ratio and knowing the distance to one photo, you can then work out the distance you travelled between the two photos. From the time code and frame counter, at 50 frames per second, you can then work out the time interval. From the distance travelled and the time interval you can then estimate your speed.

You can also check the distance travelled relative to the white line down the centre of the road, if that is available. These should have a standard spacing of 6m or 9m, depending on the speed limit. See the ABD site for further information on this.

Also if you except that you were the driver, then obtain a copy of the video clip under the data protection act. You can do this immediately. Send a letter stating, “I am making a Subject Access Request under section 7(1) of the 1998 Data Protection Act that you provide me with a copy of all the information you are holding with respect to the speeding allegation you have made against me, including any photographic or video recording you have made.”

The police may try to claim exemption, but they are not exempt and I had a ruling from the Information Commissioner's Office that the police should provide a copy of this information when you ask for it. Reference: END0092346

see more at http://www.safespeed.org.uk/forum/viewtopic.php?t=16204

It would help to include proof of identity and £10 for the fee which they can require for providing the information.

You need to do this as soon as possible to get it before expiry of the fixed penalty offer. This could show whether there were various problems, such as a car directly behind you in the laser beam that could have provided a false reading.

If you decide to fight the speeding allegation then expect a hard fight and be prepared to lose and put it down to experience. You will learn a lot, particularly about the corruption of the system, which will make you better prepared for the next time. Expect all sorts of dirty tricks from the police. You will have to be very determined.

If you can, get some professional legal advice, but that can be expensive, so you need to be convinced about your innocence, hence check your speed from the photos, and the video if you can get it.

It is better to fight the case on the inconsistencies of the operation of the speed camera, rather than trying to argue the speed camera is unreliable, which they will fight tooth and nail.
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- How does video work out the speed
The video does not work out the speed, it is merely a method of documenting the evidence. The laser gun, attached to the video recorder via a datalink, is what will be measuring your speed.

- Do they have measured points on the road they work from
Nope, you’re thinking of totally different enforcement systems.
The operator may use markers in/around the road to help form prior opinion of your speed.

- Are they laser assisted
The gun itself uses a pulsed laser to determine the speed of vehicles. It actually works by taking snapshots of distances to the target vehicle over a short time period. Once it has enough data it will then perform some calculations to deduce the speed. Note: the gun doesn’t directly measure speed, this is its Achilles' heel – it can be easily be fooled into deducing a false speed.

There are people here who are happy to help prove your actual speed, assuming you manage to get a copy of the video.

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Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign

Unfortunately they (as it sounds in this case), usually provide only one frame with details on and another which is a cropped enlargement of the registration.

Pehaps. However, both photos are usually uncropped without zoom change (digital zoom is useless, especially with video). Also, both will have their respective timestamps. It could be that the operator formed opinion as the vehicle passed so took a few frames of the plate, then waited until it was further down the road to get the 'best' result (least prone to cosine effect, as well as possibly driving faster).

The clue will be the difference of the angle of the plate between the photos.

The first photo shows the back of my Van with no view beyond either side, the width of the van takes up the full photo. The height shows the rear bumper at the bottom and the top shows only half up the back doors.

The first photo shows a time 10:30:43
Then shows a tiny N above an R then 17 then the number 23700605 and the date

The second photo shows a time of 10:30:51
Then shows the same N above the R and then 41 then the same number 23700605 and the date.
This photo also shows *-070mph and then 0348.3m

Thanks for the info. From what you describe the photos are indeed two different frames and unlikely to be cropped.

Based on the figures, you were definitely doing less than 92mph – not very useful I know.
Dr L’s method above will get you a lot closer to that real figure.

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Views expressed are personal opinions and are not necessarily shared by the Safe Speed campaign