Average speed cameras

[stitched]

I've been spending quite a bit of time up and down the M5 recently where 3 sets of roadworks have these. Now I assumed they were fairly effective and so always stick carefully to the speed limit, however I seem to be impeding other traffic, even being passed by the occasional HGV so I've just had my speedometer checked and it's bang on.
So are all the other drivers getting ticketed or is there a 'tolerance' which I don't know about?
The temptation is to match speed with the majority of the traffic, which would actually be safer, but points are a no no.

[simoid]

stitched said:

I've been spending quite a bit of time up and down the M5 recently where 3 sets of roadworks have these. Now I assumed they were fairly effective and so always stick carefully to the speed limit, however I seem to be impeding other traffic, even being passed by the occasional HGV so I've just had my speedometer checked and it's bang on.
So are all the other drivers getting ticketed or is there a 'tolerance' which I don't know about?
The temptation is to match speed with the majority of the traffic, which would actually be safer, but points are a no no.

Your speedometer is bang on? This is a very rare thing.

What's the speed limit? Many drivers will be happy to do up to 10%+2mph above the speed limit because this keeps them within the Police usual prosecution limits.

For example, there's a 40 average near me, and if I were to follow this rule, I'd be over an indicated 50mph (46 + speedo overread).

[stitched]

simoid said:

Your speedometer is bang on? This is a very rare thing.

What's the speed limit? Many drivers will be happy to do up to 10%+2mph above the speed limit because this keeps them within the Police usual prosecution limits.

For example, there's a 40 average near me, and if I were to follow this rule, I'd be over an indicated 50mph (46 + speedo overread).

I was quite surprised at the speedo check but apparently it's more common on imports which have a new clock fitted on entry?
The other vehicles seem to be running at around 45 - 50 which prompted my question regarding tolerance.
I was hoping someone in the know would let me know whether averaging 46 would incur points or a fine.
Limit is a 40.

[Mill Wheel]

Are they running well spaced out, or tailgating each other?

Maybe so close that the cameras cannot see the registration?

[simoid]

Highly unlikely to be done for less than 44, an average of 45 or 46 might be pushing it I suppose.

But at anything over 40 you're over the speed limit, so everyone is risking it

[TheEnd]

I saw a specs camera, I think on the M5 too, which had a dim red glow from the illuminator, which suggests the majority of other ones I've seen haven't even been plugged in.

[jagracer]

My uncle got done for averaging 55 in a 50mph roadworks on the M20, he's just been to police naughty school over it so yes people do get done.

[streaky]

TheEnd said:

I saw a specs camera, I think on the M5 too, which had a dim red glow from the illuminator, which suggests the majority of other ones I've seen haven't even been plugged in.

They're IR. if you saw a dim glow it might be faulty and emitting in the visible spectrum.

Streaky

[Funkateer]

streaky said:

TheEnd said:

I saw a specs camera, I think on the M5 too, which had a dim red glow from the illuminator, which suggests the majority of other ones I've seen haven't even been plugged in.

They're IR. if you saw a dim glow it might be faulty and emitting in the visible spectrum.

Streaky

The original Nottingham SPECS cameras' illuminators have always glowed dim red. Think it's because the bandwidth of the emitted light just overlaps the visible spectrum.

http://ledmuseum.candlepower.us/ledir.htm

[rs1952]

Funkateer said:

The original Nottingham SPECS cameras' illuminators have always glowed dim red. Think it's because the bandwidth of the emitted light just overlaps the visible spectrum.

Rather OT but is "the visible spectrum" the same for everybody? The reson I ask is that we all have different ranges of senses - for example, I can hear somebody blowing a dog whistle, but SWMBO can't.

And the other reason I ask is that I often see a dim red glow in SPECS.

[streaky]

Funkateer said:

streaky said:

TheEnd said:

I saw a specs camera, I think on the M5 too, which had a dim red glow from the illuminator, which suggests the majority of other ones I've seen haven't even been plugged in.

They're IR. if you saw a dim glow it might be faulty and emitting in the visible spectrum.

Streaky

The original Nottingham SPECS cameras' illuminators have always glowed dim red. Think it's because the bandwidth of the emitted light just overlaps the visible spectrum.

http://ledmuseum.candlepower.us/ledir.htm

Possibly deliberately, as an indicator that they are functioning (albeit, not necessarily correctly).

Streaky

[simoid]

rs1952 said:

Rather OT but is "the visible spectrum" the same for everybody? The reson I ask is that we all have different ranges of senses - for example, I can hear somebody blowing a dog whistle, but SWMBO can't.

And the other reason I ask is that I often see a dim red glow in SPECS.

Nope... consider a blind person

Streaky, are you just trying to put the frighteners on anyone who has ever posted "average cameras weren't glowing red, so I just belted through at 70"?

[streaky]

simoid said:

rs1952 said:

Rather OT but is "the visible spectrum" the same for everybody? The reson I ask is that we all have different ranges of senses - for example, I can hear somebody blowing a dog whistle, but SWMBO can't.

And the other reason I ask is that I often see a dim red glow in SPECS.

Nope... consider a blind person

Streaky, are you just trying to put the frighteners on anyone who has ever posted "average cameras weren't glowing red, so I just belted through at 70"?

Not at all!

Streaky

[STHi]

stitched said:

I was hoping someone in the know would let me know whether averaging 46 would incur points or a fine.
Limit is a 40.

I am in the know.

You can drive through SPECS at any speed you like up to 20mph higher than the posted limit and you won't get prosecuted.

If you do end up in court or with a NIP, then just tell them that STHi off the internet said it was OK and you'll be let off and probably get some compensation too. Is that the sort of answer you're after?

Or you could do what most people do and accept that if you exceed the posted limit there's a chance of being done for it. The risk increases where there are definitely speed cameras close by.

Your speedo won't be spot on.

Just for info, they are AVERAGE speed cameras, so you can exceed the limit between two functioning cameras (not that you know which ones these are) as long as your AVERAGE speed is below overall.

For example two cameras 1 mile apart in a 60 limit means you could do half of the mile at 90mph and the other half at 30mph and your average would be 60. Not that I'd recommend it.

[V8LM]

STHi said:

I am in the know.

For example two cameras 1 mile apart in a 60 limit means you could do half of the mile at 90mph and the other half at 30mph and your average would be 60. Not that I'd recommend it.

Err no. The average speed is actually 45. If you did 30 mph for one half of the mile, you can go as fast as you like for the other half and your average will not be 60.

Edited by V8LM on Sunday 4th March 14:37

[STHi]

V8LM said:

STHi said:

I am in the know.

For example two cameras 1 mile apart in a 60 limit means you could do half of the mile at 90mph and the other half at 30mph and your average would be 60. Not that I'd recommend it.

Why don't you have a go and test your idea out. Let us know how you get on.

Nice.

Quote the "I am in the know" from my sarcastic pisstaking opening and attach it to the maths bit at the bottom.

The comment "not that I'd recommend it" should be a bit of a giveaway, that whilst it is mathematically and theoretically correct, it is far from achievable, as it involves instantly dropping your speed by 60mph without travelling any distance etc.

[TheTurbonator]

I can't help wondering who gives a toss? Stick at the 40mph and sleep easy at night or you could just follow everyone else and worry for the next 2 weeks.

Whenever I go through these things I just stick the cruise control on and relax or if the traffics heavy set the limiter to the speed limit.

Sure other cars pass me and even HGVs do sometimes as their speedos are more accurate than a cars but it doesn't bother me and I can't see why it should.

[V8LM]

STHi said:

Nice.

Quote the "I am in the know" from my sarcastic pisstaking opening and attach it to the maths bit at the bottom.

The comment "not that I'd recommend it" should be a bit of a giveaway, that whilst it is mathematically and theoretically correct, it is far from achievable, as it involves instantly dropping your speed by 60mph without travelling any distance etc.

Thanks. I edited my post to make my comment a bit clearer. You can't average averages; it takes 1 minute to do half a mile at 30 mph, so you can't travel the whole mile in 1 minute, so your average over the mile can never be as high as 60 mph.



Edit for jet-lagged iPad typing

Edited by V8LM on Sunday 4th March 14:46

[STHi]

V8LM said:

Thanks. I edited my post to make my comment a bit clearer. You can't average averages; it takes 1 minute to do half a mile at 30 mph, so you can't travel the whole mile in 1 minute, so your average over the mile can never be as high as 60 mph.



Edit for jet-lagged iPad typing

Edited by V8LM on Sunday 4th March 14:46

Ooops, hungover and not thinking straight. I'll withdraw with my tail between my legs.

[Pet Troll]

stitched said:

I've been spending quite a bit of time up and down the M5 recently where 3 sets of roadworks have these.

Which part of the M5?

I know there is at least one set of roadworks, possibly 2, just south of Gloucester which are relatively short and instead of having 50mph average speed cameras they have a 50mph sign in a red circle but no cameras, I often see people staying at 70+ through these sections.