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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