Safe Speed Forums

Do you think he waits for a set number of questions that he can't/won't answer before submerging til he hopes we've forgotten about them?

Perhaps we should start a sweepstake?

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Regulation without education merely creates more criminals.

I don't think Avon & Somerset have a Scam Partnership any more, so this is of academic interest only, methinks.

I've got a fiver on sunday ....

Perhaps this could take over from the caption comp and give a prize to the person who causes Greenshed to submerge.

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My views do not represent Safespeed but those of a driver who has driven for 39 yrs, in all conditions, at all times of the day & night on every type of road and covered well over a million miles, so knows a bit about what makes for safety on the road,what is really dangerous and needs to be observed when driving and quite frankly, the speedo is way down on my list of things to observe to negotiate Britain's roads safely, but I don't expect some fool who sits behind a desk all day to appreciate that.

Are figures not available as to how many drivers are caught speeding AFTER attending a course?

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Time to take responsibility for our actions.. and don't be afraid of speaking out!

so how does one calibrate a gun TIM[/quote]

Place the barrel of the gun in one of the bodily openings and point it at one of the other openings, if it is correct then the bullet will exit through the intended bodily opening

But to calibrate a speed gun, so that it gives accurate readings, is more difficult

Although thinking about it there is not a great deal of difference between annually and anally

But to calibrate a speed gun, so that it gives accurate readings, is more difficult

Although thinking about it there is not a great deal of difference between annually and anally[/quote]

so you constantly say, have you ever realigned a sighting scope

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now retired

I have, with rather more life-or-death consequence, why, what's the relevance of whether or not one has first-hand experience of doing it?

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Regulation without education merely creates more criminals.

so you constantly say, have you ever realigned a sighting scope[/quote]

Yes probably many more times than you have, especially as operators, including ex ones, are not allowed to adjust the scope alignment.

This assumes they actually know how to correctly check the alignment

meoww, as an ex operator there was never a reason to realign, purely and simply because they do not go out of alignment, althought the manual clearly states the procedure



and how is that, are we talking the pistol stance, the over shoulder stance, under knee stance or make it up as we go along stance

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now retired

Oh dear what arrogance to use the word NEVER, rarely I might just accept.

But here is a challenge to Camera Operator describe in detail how the alignment checks, yes in the plural, are carried out, what you should see, what you should hear and any range reqquirements.

These checks are the scope alignment check and the cross hair alignment

My money is on you will not do it, for fear of being shown to be wrong, or you will do it and get it wrong.

There again you may just ignore this as you have done before when the questions get too hard, See last post general chat "naughty or dull boy"

viewtopic.php?f=13&t=24869

how can you have cross hair alignment on a hand held device

but for SCP equipment

1. switch on 4 8 - beeps internal software pass check
2. at base station, from 2 pre measured points in whole meteres (floor pin to wall marker), independantly verified with a steel rule, with the gun powered up and with the handle above the floor piin obtain a reading of 0 mph at the relevant distance, i believe it had to be in exess of 80 m
3. at base station again at a predetermined point pt the device into TTmode, pan the red dot vertical and horizontal, the audible tone advices when the laser hits the target
4. repeat 1
5. at site select a suitable target with the red dot within the area that vehicles are to be targetted, by way of thumb screws align the crosshairs to the target, obtaining a reading of 0mph
6. repeat 2
7. repeat 3

that is all that is required to satisfy the requirements of an operator, it in the manual

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now retired

I have to admit that I was surprised by Camera Operator’s answer, pleasantly surprised to boot.

He is the very first operator I have ever come across who actually admits to knowing the correct way to align the red dot with the cross hairs, item 5.

However I have to address the alignment of the red dot with the centre of the laser, items 3 and 7.

This is not a direct criticism of Camera Operator, but of the manuals and the training.

From my experience operators, ever though they are trained, do not know the relevance of this check or the correct way to do it.

Operators are told that this device never, sometime the word used is rarely, goes out of alignment.

Whereas I might accept rarely, no one in their right mind would ever accept never.

This though makes the assumption that the alignment of the red dot and the centre of the laser is accurate when the device is initially received from the manufactures and then after each and ever annual calibration.

Before any operator carries out an alignment check, they must have a basic understanding of what they are actually checking.

This is something that is very rare indeed.

When the laser pulse leaves the LTI it has a beam width, which means it increases is size the further from the LTI is goes.

The quoted beam width is 3mrads.

This means the width of the laser increases by 3mm per mtr of travel from the LTI, plus the starting width of the laser.

The approximate shape of the laser is square with rounded corners.

Therefore at a range of 100mtrs the laser is approximately 0.339mtr wide and at a range of 600mtrs the laser id 1.839mtrs wide.

The beam width of any electromagnetic pulse is measured at the “Half Power Points”.

What this means is that at lower ranges and/or from highly reflective targets, return signals can be received from outside the quoted beam width.

The alignment of the red dot has to be made with the centre of the laser and this has to be carried out with great care and precision. It can only be done slowly.

However to carry out this alignment the operator has to be aware that the red dot and the laser are physically separated at the LTI.

To be specific the red dot of 5cm vertically above the laser and should always run parallel to the laser.

This means that no matter what range of the target is the red dot will always be 5cm above the centre of the laser.

This 5cm does not create any problems providing it is always exactly parallel to the laser.

However any angular error between the red dot and the centre of the laser, in any plane, at the LTI will give an error in the alignment at the target.

To put this into perspective an angular error of just 0.1 degree at the LTI will give a physical separation of the red dot and the centre of the laser of 0.17mtrs at a range of 100mtrs and 0.87mtrs at a range of 500mtrs.

This means the alignment of the red dot and the centre of the laser has to have an error of considerably less that +/- 0.1 degree.

To be able to get any where near this level of accuracy means that all operators have to know exactly how to locate the centre of the laser.

I have never seen an alignment check that could even remotely be considered to have this level of accuracy.

To check the alignment the operator must select a suitable target.

This target should have a straight vertical and horizontal edge, with nothing in the immediate background, preferably just sky.

The operator, after selecting the tt mode, moves the LTI slowly from off the left or right side of the vertical edge of the target, noting when the tone starts to increase in both pitch and level.

Then he notes when the peak audio, in both pitch and level, occurs. This should be when the red dot is on the very edge of the selected target.

He then checks that the opposite occurs as the LTI is moved off the other side of the target.

He then repeats the same for the horizontal edge of the target, remembering that in this case the red dot is 5cms above the centre of the laser.

If the device passes this check then he can safely say the red dot and laser are correctly aligned.

However this check must be carried out slowly and with great care and precision.

It cannot be carried out a speed, no matter how experienced the operator is.

I have never seen this check carried out, in what I consider an acceptable manner, by any operator.

However I do not believe this is the fault of the operators it is, in my opinion, due to lack of correct training.

This may be because the trainers themselves do not know the correct way to carry out this check and this is therefore the fault of the suppliers.

However the integrity and accuracy of all the LTI’s rely on this check being carried out correctly.

If the return are not coming directly from the operator’s intended target, then any calculations of speed cannot be relied upon to be correct for that target.

really well i will sleep happily tonight knowing that, although what i stated above has been said by two different operators at trial with yourself, basic stuff IMO

and just for the record the red dot is never aligned to the crosshairs, the cross hairs are aligned to the red dot,

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now retired

I think that it is pretty obvious to say, that once the red dot and cross hairs are aligned, that they can be said to be aligned WITH each other, regardless of which has to be moved TO line up with the other. Which is what Tim said, without having to split (cross) hairs....

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My views do not represent Safespeed but those of a driver who has driven for 39 yrs, in all conditions, at all times of the day & night on every type of road and covered well over a million miles, so knows a bit about what makes for safety on the road,what is really dangerous and needs to be observed when driving and quite frankly, the speedo is way down on my list of things to observe to negotiate Britain's roads safely, but I don't expect some fool who sits behind a desk all day to appreciate that.

[quote]
To check the alignment the operator must select a suitable target.

This target should have a straight vertical and horizontal edge, with nothing in the immediate background, preferably just sky.[quote]

I wonder how many "targets" selected for alignment, are actually what would be classed as "suitable"?

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My views do not represent Safespeed but those of a driver who has driven for 39 yrs, in all conditions, at all times of the day & night on every type of road and covered well over a million miles, so knows a bit about what makes for safety on the road,what is really dangerous and needs to be observed when driving and quite frankly, the speedo is way down on my list of things to observe to negotiate Britain's roads safely, but I don't expect some fool who sits behind a desk all day to appreciate that.

but by splitting the split hair again with the above statement, it is obvious that you don not know how the system works



some one is getting confused again

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now retired

Really? Are you going to maintain that the system you have used is actually in some way unique and outwith the general principles of aligning optics for a desired point of incidence?

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Regulation without education merely creates more criminals.

Seriously mate, are you hard of thinking? The quote says the target must be suitable, graball wonders 'aloud' if the targets chosen are always what would be classed as suitable.

Is the confused someone you?

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Regulation without education merely creates more criminals.

mmmmm, I do wonder at the intelligence of camera partnership members (or ex ones) when you consider GS's Maths (In)ability and Cam Ops lack of joined up thinking.


Perhaps he can enlighten us, as to what he might consider a suitable target for alignment, that he might use? I know what I would use but won't give him any clues yet cos he's supposed to be the "professional" here.

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My views do not represent Safespeed but those of a driver who has driven for 39 yrs, in all conditions, at all times of the day & night on every type of road and covered well over a million miles, so knows a bit about what makes for safety on the road,what is really dangerous and needs to be observed when driving and quite frankly, the speedo is way down on my list of things to observe to negotiate Britain's roads safely, but I don't expect some fool who sits behind a desk all day to appreciate that.

'Where are the speed camera men and their friendly responses?'

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