Speeding - fines - court

AdrianC

Biggus_Dickus said:

I was doing about 85 on the A64 (York bypass)

Assuming that's NSL d/c, then that's within tea-and-biccies territory.

The article below quotes: “For technical reasons, a speed van will only remain in a certain spot for 90 minutes” ...what’s all that about? 

Simple reason, I suspect...
Local FB groups.

"Camera next to XYZ - be careful!"

Car_54

Biggus_Dickus said:

Are they parked and left unattended or is there always a Rozzer in attendance?

As explained in the article, yes, they can be left unattended. When attended, the operator is not usually a police officer.

However, not everything in the article is true. E.g. having points on your licence will NOT prevent you being offered a course.

Biggus_Dickus

AdrianC said:

Biggus_Dickus said:

I was doing about 85 on the A64 (York bypass)

Assuming that's NSL d/c, then that's within tea-and-biccies territory.

The article below quotes: “For technical reasons, a speed van will only remain in a certain spot for 90 minutes” ...what’s all that about? 

Simple reason, I suspect...
Local FB groups.

"Camera next to XYZ - be careful!"

Wouldn’t that be a good thing though?...the Rozzers say it’s as much about speed deterrent as enforcement.

p.s. I'm not on Facebook,...I might have to do something about that.😁

[Deleted User]

Some apps including some Google one apparently (and Waze I'd assume) will alert to camera vans parked up - they work on users adding alerts - which is a whole other ball game, using a phone to update an app while driving, I'm sure they all pull over and turn the engine off first...

49mph on a GPS, assuming 100% accurate for sake of argument, speedo would have been showing 50-55 easily, speedos can over report by 110% of the vehicle speed + 6.25mph e.g. showing 50.25mph when car is really doing 40. Taking 10% as an example, 55mph on speedo - 10% =  49.5mph

Car_54

Deleted_User said:

49mph on a GPS, assuming 100% accurate for sake of argument, speedo would have been showing 50-55 easily, speedos can over report by 110% of the vehicle speed + 6.25mph e.g. showing 50.25mph when car is really doing 40. Taking 10% as an example, 55mph on speedo - 10% =  49.5mph

Mathematics alert!

1. They can only over-report by 10% plus 6.25, not 110%.

2. At 10%, 55mph on the speedo is 50 mph. The 10% is calculated on the vehicle speed, not the reported speed.

Manxman_in_exile

Car_54 said:

Deleted_User said:

49mph on a GPS, assuming 100% accurate for sake of argument, speedo would have been showing 50-55 easily, speedos can over report by 110% of the vehicle speed + 6.25mph e.g. showing 50.25mph when car is really doing 40. Taking 10% as an example, 55mph on speedo - 10% =  49.5mph

Mathematics alert!

1. They can only over-report by 10% plus 6.25, not 110%.

2. At 10%, 55mph on the speedo is 50 mph. The 10% is calculated on the vehicle speed, not the reported speed.

Am I understanding that correctly?

So at an actual speed of 50mph your speedometer could legally read as high as 61mph? 

(50 + 5 + 6.25 = 61.25)

I knew about the 10% but not the additional 6.25mph bit.

Arsenal2019

Okay,, so with all of the above mathematics going on, if my GPS dash cam said 49MPH,.. I would’ve been doing 49 or less?

TBagpuss

Arsenal2019 said:

Okay,, so with all of the above mathematics going on, if my GPS dash cam said 49MPH,.. I would’ve been doing 49 or less?

No. They are talking about the speedometer in your car, not the GPS.

And even with the speedo, it doesn't mean that you would have been going slower, just that you might be. Legally, a speedo must not show a lower speed that you are actually travelling, but can show a higher speed, within the tolerances FarFetch explained, so manufacturers will calibrate them with that in mind. 

So, if you had looked at your dashboard and your speedo was reading 49 mph, you could be fairly confident that you *weren't* doing more than 49.

The dashcam will be using GPS to work out your speed based on where your car was each time it 'pings' the satellite - so  it's closer to an average speed check, although it's averaging it over very short periods so ought to be fairly accurate except if you were accelerating or decelerating sharply - so if you were doing 55 but slammed the brakes on and went down to 30  when you saw the police camera it might register a speed lower than 55. How accurate it is will depend on factors such as speed, (it's more accurate at higher speeds), signal quality etc.  If it is a built in system it may also 'talk' to your car to increase accuracy.

Arsenal2019

TBagpuss said:

Arsenal2019 said:

Okay,, so with all of the above mathematics going on, if my GPS dash cam said 49MPH,.. I would’ve been doing 49 or less?

No. They are talking about the speedometer in your car, not the GPS.

And even with the speedo, it doesn't mean that you would have been going slower, just that you might be. Legally, a speedo must not show a lower speed that you are actually travelling, but can show a higher speed, within the tolerances FarFetch explained, so manufacturers will calibrate them with that in mind. 

So, if you had looked at your dashboard and your speedo was reading 49 mph, you could be fairly confident that you *weren't* doing more than 49.

The dashcam will be using GPS to work out your speed based on where your car was each time it 'pings' the satellite - so  it's closer to an average speed check, although it's averaging it over very short periods so ought to be fairly accurate except if you were accelerating or decelerating sharply - so if you were doing 55 but slammed the brakes on and went down to 30  when you saw the police camera it might register a speed lower than 55. How accurate it is will depend on factors such as speed, (it's more accurate at higher speeds), signal quality etc.  If it is a built in system it may also 'talk' to your car to increase accuracy.

Update - I went out in my car earlier and drove at 30 mph (digital clock). I then plugged in the dash cam and watched the footage back. It said I was travelling at 28-29 mph .
So I’m guessing this means that my dash cam when it’s said 49MPH would be wrong, and that I was travelling faster

Does anyone know how long it takes for a speed camera to focus onto you before it gets a reading?

TooManyPoints

Most cameras can "ping" you up to a kilometre away.

Regards speed measurements by GPS, they should not be relied upon. They work by measuring your speed over a straight line between two points. Fine if you're travelling on a straight road but they will under record if the road is not straight because you will have travelled a greater distance than that used to calculate your speed.