Ontariohighwaytrafficact.com

Hey guys,

Just wondering if I can get some help on what to do for this ticket. I have a court date on August 17th. I simply cannot afford this. I haven't had an offence in years, and pay attention to my speeds now. One night when I was too focused on the road and not the speedometer, I get pulled over. What do you guys think is the best option?

Along with the notes, I was also provided 3 pages of the user manual for the radar gun.

It is a LIDAR not RADAR, but that is neither here nor there. Can you post the pages from manual?

The officer was approximately 300 meters away based on my calculations using beam width of .9m and lidar gun specs.

What was volume of traffic? Obviously it was dark but was it raining ( I can't make out the RDS conditions)?

Basically the officer is stating he is sure he wasn't off by 0.9m at a distance of 300m aiming at a car's registration plates going, he claims, 121 km/hr, with headlights on probably blinding him to a degree. As well, he didn't sweep the lidar gun while trying to target you way off in the distance in the dark. Okay.

His requalification is 3 years old at time of ticket (I am having trouble seeing the date.) Obviously training isn't taken seriously. I remember I read in Alberta it needs to be done once a year, and even though in Ontario the standards arent explicitly defined that shouldn't mean they are significantly less. I seriously doubt he read the manual Feb 2016 on his own. Find out how many pages it is and ask him if he read the whole manual with the follow-up being approximately how many pages is it?

Speedtaxed wrote:

The officer was approximately 300 meters away based on my calculations using beam width of .9m and lidar gun specs.

What was volume of traffic? Obviously it was dark but was it raining ( I can't make out the RDS conditions)?

Basically the officer is stating he is sure he wasn't off by 0.9m at a distance of 300m aiming at a car's registration plates going, he claims, 121 km/hr, with headlights on probably blinding him to a degree. As well, he didn't sweep the lidar gun while trying to target you way off in the distance in the dark. Okay.

His requalification is 3 years old at time of ticket (I am having trouble seeing the date.) Obviously training isn't taken seriously. I remember I read in Alberta it needs to be done once a year, and even though in Ontario the standards arent explicitly defined that shouldn't mean they are significantly less. I seriously doubt he read the manual Feb 2016 on his own. Find out how many pages it is and ask him if he read the whole manual with the follow-up being approximately how many pages is it?

No, 0.9m is the width of the laser beam at a distance of 300m. Width of LIDAR beam is approximately one metre wide at 300 metres, compared to the registration plate width of 30 cm, ensuring that little of the signal is scattered to following vehicles. Aiming at front middle of vehicle will suffice.

Notes (I believe) indicate he is an operator/trainer , re-qualification only required every 5 years for a trainer.

The officer wrote in his notes the beam width was 0.9m. It changes over distance. So the officer had to be approximately 300 meters away when he obtained the reading. If the beam width is 0.9m that means officer can miss the plate by that much and still theoretically get laser beams back from hitting it and therefore readings. However, it also means the operator could be measuring readings from any object 1.8 meters away from his car (I. E another lane of traffic or almost anything really that he is unaware of 300 meters away in dark).

Beam width is nOT the officer's friend. I have never operated a radar/lidar gun and think speed measuring devices should only be used to measure pitch speeds and baseball exit velocities. With that said, I would imagine this particularly unit calculates the distance of the target by bounce back time and then gives the approximate beam width based on the distance calculation which the officer wrote down in the notes under that section.

LIDAR calculates the speed of vehicle based on Time Of Flight. It sends out a pulse and then waits for it to come back. It uses Infrared laser, and the beam travels at the speed of light, so it can then calculate the distance based on how long it took to get there and back. It will then take several distance readings over a time period (about 0.3 seconds) and then it calculates speed based on the change in distance.

The beam width or beam divergence is measured in milliradians or mrads and is around 3 mrads for most Lidar units which at 300meters distance would be about 0.9 meters in diameter.

The purpose of having a standardized template for the officer's notes which has beam width specified is so the officer will document what the beam width is at the distance of the lidar reading. The officer is not putting the beam width of the lidar gun at 300 meters there. The reading was taken at approximately 300 meters away so that is why the beam width corresponds to what it would be at 300 meters. My guess is that the lidar gun indicates the beam width with the reading. The reason why it has to be indicated probably is that is important to know potentially how wide the beam is because it could be measuring objects beside the intended target at the width of the beam.

LIDAR does NOT show you the beam width. It only shows you distance to target and the target speed. You need to calculate the beam width based on the specs given by manufacture (which again is usually 3 mrads).

Looking at the disclosure, I can not read what it says the distance is...

H/L 121 @ 2??

Can anybody else dechiper this?

Anyways it does not look like the distance is 300m in which case the officers beam width calculation is incorrect, so there is possibility to attack his understanding of unit based on that.

I meant to write including objects in reading @ 2X width of beam.

Really not sure how calculation was made or if it was taken but he really can't say what he could've hit in a 0.9 m radius circle 300 meters away in the dark. Yeah if it contradicts distance reading you go to town on his training.

Can anyone really target a moving object 300 meters away in the dark without a stand or night vision equipment and say for sure they hit their intended target?

My experience using Lidar is that even in the daylight, at 1000ft/300m the target vehicle is no bigger than the little dot in the sight and it is hard to keep the dot on the vehicle at that distance. So yes at night it would almost impossible at that distance.

At those distances you have a very likely possibility of sweep errors which means the readings are bouncing off different parts of the vehicle because you can not hold it to one specific spot on the vehicle which means the speed calculation will not be correct.

At 300m a motor vehicle shows up very well in the sight...at that distance the operator would be using the 8X magnification sight...Depending on the lighting situation of where the alleged offence took place, the officer may well have been able to see clearly enough to get a good shot...was there good ambient light from street lights or was it down a dark, unlit highway?...the lidar does not give any indication as to lidar beam width, just speed and distance...in fact, the distance is not even needed to be proven in court to get a conviction for speeding, a lot of officers do not put the distance down in their notes...the cross hairs in the sight are lit so it is easy to get a good shot at night...

Not all Lidars have a magnified sight. In fact most don't.

Well, if you look at the disclosure notes you will see that the lidar used was the Laser Atlanta Speed Laser which does, in fact, have it...

I have used one Lidar with a magnified sight (2x) but I can not remember which one it was.

I found copy of Laser Atlanta manual (2003 version) and it makes no mention of magnified sight in that manual. Anyways, if you have used it then I assume you are correct about the sight.

However would be a good question to ask the officer "Is the sight magnified?"

The officer can use the regular sight or flip the other one over if they want the 8X magnification...operator preference

What is FOV at 8x magnification?

FOV

Bottom line on this one, as I see it: Very good notes, officer is an operator and trainer, looking at badge # I will guess this person has years of experience, the technical arguments being raised are not good...with his training and experience things like how wide is the beam, sweep error or visibility at night can be easily explained...I say talk to prosecutor and see what kind of deal they will be willing to give...perhaps lower speed down to 3 points or even disobey sign at 2 points...

What is the Field of vision at 8x magnification? Can you answer that question or not?

There will be sweep error.

I do not know what the field of vision will be...there may be sweep error if the lidar was being moved while getting a reading...the average of least squares will guard against the sweep errors...sweep errors is more common when hitting the side of a big target such as a tractor trailer, taking a shot along the long box trailer...if the lidar hit the front plate, or headlight there is very little chance of sweep error...if you move from the front grill area to a higher point further back while taking a reading then it is possible, but I still say with the operator's training and experience that is not a good point of attack...

Can you expand on the average of least squares will guard against sweep error? Is that your personal theory?

What will happen to the lidar algorithm if the sweep error is bad enough?

Do you know why FOV is important here?

No, it is not my personal theory...one lidar reading is compared to the one before it...there needs to be a few readings in agreement to produce a valid reading...if there is a sweep error the difference in the readings would be noted and tossed out (by the lidar)...just dumbing it down a bit...

You stated the average of least squares will guard against sweep error. I would like you to expand on the theory that you learned in training.

You can dumb it down anyway you like. If you have 2 sweep error readings and 3 "good" ones how will the average of least squares guard against the 2 sweep error readings?

It recognizes a sweep error as it is happening and won't display a reading...it will then get another reading on the other part of the vehicle, if the next readings are in agreement it will display the reading...

argyll wrote:

FOV

LMAO!!!!!

Zatota wrote:

argyll wrote:

FOV

LMAO!!!!!

I did not get it at first... now I do. lol

The average of least squares MAY guard against SOME sweep errors, but is not a guarantee that it will eliminate all sweep errors.

People are getting hung over the term least squares. All you need to know is that an average doesn't guard against outlier results and is affected by them.

The lidar algorithm doesn't discard sweep error results. It discards outlier results. If there is too much sweep the sweeping results might not be the outlier result.

On 8x magnification there is less light and image stability than no magnification. The FOV (no I will not) is 1/8 as much as normal view. A 300 meter shot is considered long (er) range and a stand should be used. In reality, whether officer's are cognizant of the fact or not, they can't keep their hands steady enough and have to pan too much on a 80km+ moving target 300 meters out in the dark. Any intelligent person would recognize there would be huge uncertainty in any reading coming back at that distance not only because of sweep error but because of beam width and inclusion of other objects at potentially a 1.8 meter radius circle around target.

There's not much panning involved when the cross hairs are a licence plate of a vehicle coming straight at you.

There is more panning than you realize as target is moving rapidly and has to stay in middle of cross hairs. Also as I stated there is no stand, right? That means there is handshake. Then you have the problem of beam width and 1.8m radius around car that lidar is all the time measuring at 300m.

The lidar/radar guns are only tested by the manufacturer under ideal conditions so as not to fail. I know for a fact the police force doesn't test them or maintain them and claim it's done by a 3rd party. That's fraudulent as they literally have no idea if they are even being maintained and only passed it off to a 3rd party so they don't have to answer these questions very easily in court. An appeal judge that I had didn't even know that and had to take a 3 hour recess to sort that fact along with others out.

Do you honestly think you could hit a car 300 meters away in the dark moving at between 80 to 121km /hr with a gun? I don't even think a sniper can make that shot most of the time from the ground nevermind an overweight police officer that's very unskilled compared to the sniper sitting in an upright position possibly with a donut or coffee in his other hand. It is the same principle except instead of bullets you are firing off light beams. Yes you don't have a recoil, but still, you can't make the shot and you know it.