On Fri, 18 Feb 2005 11:31:27 GMT, Richard J. wrote:

7. It is illegal to tamper or interfere with your vehicle number plate."

One frequently sees plates that are so filthy that no camera would pick
up any image. Clearly the drivers take this rule very seriously indeed.
--
http://gallery120232.fotopic.net/p9632896.html
(33 117 in the middle (yes, middle!) of a train at Weymouth Q in 1989)

In message , Chris Tolley
writes

One frequently sees plates that are so filthy that no camera would pick
up any image.

The most common type of device (GATSO) makes an infra-red image as well
as a photographic one. Neither dirt nor, I suspect, the reflective spray
that is the subject of this thread, will prevent an infra-red image of
the number plate being taken.

--
Paul Terry

On Fri, 18 Feb 2005 18:53:51 +0000, Paul Terry wrote:

In message , Chris Tolley
writes

One frequently sees plates that are so filthy that no camera would pick
up any image.

The most common type of device (GATSO) makes an infra-red image as well
as a photographic one.

I didn't know that. Fascinating.

--
Not a good picture, but certainly an informative one:
http://gallery120232.fotopic.net/p10862746.html
(A "surfer" hanging on to the back of a Manchester tram in 2000)

"Chris Tolley" wrote in message
...
On Fri, 18 Feb 2005 18:53:51 +0000, Paul Terry wrote:

In message , Chris Tolley
writes

One frequently sees plates that are so filthy that no camera would pick
up any image.

The most common type of device (GATSO) makes an infra-red image as well
as a photographic one.

I didn't know that. Fascinating.




NOT TRUE.

2 standard colour 35mm exposures using flash illumination. Nothing infrared
involved with Gatsos.

Other systems using Automatic Number Plate Reading Video cameras (such as
SPECS average speed enforcement system) use infrared illumination. Gatso
doesn't.

In message , Graeme
writes

NOT TRUE.

2 standard colour 35mm exposures using flash illumination. Nothing infrared
involved with Gatsos.

So are websites such as http://www.termsys.demon.co.uk/gatso.htm wrong
when they claim ...

The photographs taken will be both normal and infra-red. (The
infra-red will 'see' your registration mark when the vehicle is
caked in dirt.) Also, to collect the proof, two photographs are
taken in quick succession, so that the distance travelled can be
seen.

And http://www.benlovejoy.com/speedtrapdetectors.html ... with its
picture of "A forward-facing infra-red Gatso hidden behind a sign"

Gatsometer's own site claims that they make GATSOs "with optional
infra-red flash", but I have no idea if these are used in the UK.

Other systems using Automatic Number Plate Reading Video cameras (such as
SPECS average speed enforcement system) use infrared illumination. Gatso
doesn't.

I believe the Truvelo system also uses I-R.

Basically, if I-R is being used at all, and it certainly appears to be,
then I cannot see how a reflective spray varnish will help to avoid it.

--
Paul Terry

In article ,
(Paul Terry) wrote:

I believe the Truvelo system also uses I-R.

Basically, if I-R is being used at all, and it certainly appears to be,
then I cannot see how a reflective spray varnish will help to avoid it.

Truvelo must use Infra red, because to have a forward facing flash would
be dangerous.

--
Paul Cummins - Always a NetHead
Wasting Bandwidth since 1981

"Paul Terry" wrote in message
...
In message , Graeme
writes

NOT TRUE.

2 standard colour 35mm exposures using flash illumination. Nothing
infrared
involved with Gatsos.

So are websites such as http://www.termsys.demon.co.uk/gatso.htm wrong
when they claim ...

The photographs taken will be both normal and infra-red. (The
infra-red will 'see' your registration mark when the vehicle is
caked in dirt.) Also, to collect the proof, two photographs are
taken in quick succession, so that the distance travelled can be
seen.

Yes - they are wrong.

Serco's back office systems include wet-film viewers that can invert the
images and this often helps to see plates that can't be seen normally.


And http://www.benlovejoy.com/speedtrapdetectors.html ... with its
picture of "A forward-facing infra-red Gatso hidden behind a sign"

Gatsometer's own site claims that they make GATSOs "with optional
infra-red flash", but I have no idea if these are used in the UK.


If you want it from the horse's mouth - why don't you ask the Warwickshire
or Sussex Partnerships who will be delighted to tell.


Essex have experimented with front-facing photography to supplement their
successful (!) Gatso-based campaign, but they do NOT have approval (to the
best of my knowledge) as these images are triggered in the same way as a
slave flash gun is in photography. There is a big demand to identify
offending drivers and this is Gatso's attempt to help Essex achieve that
result.

Again, to my knowledge the optional IR illumination that Gatso offer is not
approved for use here. They have a shed load of products that are used
elsewhere in the world, but that are not approved for use here.

Other systems using Automatic Number Plate Reading Video cameras (such as
SPECS average speed enforcement system) use infrared illumination. Gatso
doesn't.

I believe the Truvelo system also uses I-R.


Truvelo have approval for a front facing camera that uses three piezo strips
in the road and NO radar, but due to it's front-facing nature, they are
obliged to use a magenta filter over the flash to avoid blinding on-coming
(offending!) drivers.

It's not IR.

Basically, if I-R is being used at all, and it certainly appears to be,
then I cannot see how a reflective spray varnish will help to avoid it.

--
Paul Terry

In message , Graeme
writes

So are websites such as http://www.termsys.demon.co.uk/gatso.htm wrong
Yes - they are wrong.

I see.

Truvelo have approval for a front facing camera that uses three piezo strips
in the road and NO radar, but due to it's front-facing nature, they are
obliged to use a magenta filter over the flash to avoid blinding on-coming
(offending!) drivers.

It's not IR.

What is your evidence for that? Sorry to sound doubtful, but Google for
Truvelo "infra red" and you will find many, many websites like
http://www.radardetectors.co.uk/faqs.htm ...

Q What is the Truvelo system?

A This is easy to spot because it's a forward facing camera with
pressure strips across the road in front of it. The time and distance of
a vehicle's axles passing over these strips are measured to calculate
speed and a photo is then taken if you are considered to be over the
speed limit. Like the SPECS system the picture is taken using infra red
so you do not see a flash.

Or is this yet another website that is wrong?

--
Paul Terry

On Sat, 19 Feb 2005 18:01:44 +0000, Paul Terry
wrote:

And http://www.benlovejoy.com/speedtrapdetectors.html ... with its
picture of "A forward-facing infra-red Gatso hidden behind a sign"

Look closely at the picture - it's NOT a Gatso. It's a Truvelo (and so
has a magenta filter over the flash - it's NOT infra-red).

--
Philip

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