PDA

View Full Version : Does Laser/Lidar work in the rain



onetxguy
05-11-2009, 10:27 PM
I have kind of a silly question. Today when driving home I passed a city officer on the shoulder running laser. What seemed funny to me was that it has raining/drizzling at the time. The mist from the cars and trucks was so predominate that my laser detector picked him up not only way down the road, even though he was directing the laser in another lane, but even as I passed beside him. So my question is; do laser guns work with considerable moisture in the air?

While I think it silly for an officer to be sgtanding out in the rain just to catch a speeder, I thought it sillier that he would be using technology that in theory would have a problem with light refraction in rainy conditions. I know that a you guys dont typically like to discuss the technical aspects of radars, but this seemed odd to me.

For those that wonder why I have a detector in my vehicle, I tend to have a heavy foot and it is a good reminder to slow it down when it goes off. I know the implications of getting pulled over with it from your standpoint and accept that I have already had my warning. I try to abide by the prima fascia speeding laws in my state but sometimes I do go a little faster then other moving traffic. :o

Anyway, I am just curious and would appreciate an answer. Thanks for doing the good work you guys do.

Fuzz
05-11-2009, 10:50 PM
Without going too far into its technical operations here is a direct quote from one of the Lidar companies websites

The ProLaser III's selectable environmental mode minimizes the range-limiting effects of poor weather conditions. You'll experience improved operation in rain and snow — even when aiming through glass or a windshield. It has pinpoint accuracy you can rely on. With ProLaser III, speeders simply don't have a chance.

R.A.B.
05-11-2009, 10:50 PM
If he was standing in the rain using it, then it obviously works in the rain.

2wheeldep
05-11-2009, 10:51 PM
Yes, it works in the rain.

RoadKingTrooper
05-11-2009, 10:54 PM
Yes


Have the best rainy day ever!

violet_eyez
05-12-2009, 12:19 AM
Okay, i gotta ask a follow-up question

Why is the officer standing OUT in the rain? Does he not have a car he could sit in to lidar traffic? If according to the manufacture clam it should work spiffy right through windsheilds

Was he just standing on the side of the road with no car? I dont see how that would be an effective way to catch speeders....less he can run really really fast ^^

lol im sorry but this just doesnt seem to add up to me. Any explanation on why you would be getting soaked standing outside of your car popping speeders when you can do it just as easily inside the car

SgtScott31
05-12-2009, 12:44 AM
Okay, i gotta ask a follow-up question

Why is the officer standing OUT in the rain? Does he not have a car he could sit in to lidar traffic? If according to the manufacture clam it should work spiffy right through windsheilds

Was he just standing on the side of the road with no car? I dont see how that would be an effective way to catch speeders....less he can run really really fast ^^

lol im sorry but this just doesnt seem to add up to me. Any explanation on why you would be getting soaked standing outside of your car popping speeders when you can do it just as easily inside the car

Because he felt like it. Although you can shoot through the windshield, it is not recommended with some LASER/LIDAR models. As long as you were not the one in the bullseye, why should you care?

I have ran LIDAR outside of my vehicle plenty of times. I simply walk out into the lane and pull the vehicle over. Should the vehicle fail to stop, I get in my car and get them down the way. Now they face more than just a speeding charge. ;)

JDCOP
05-12-2009, 01:20 AM
I mix it up whether it be in car or out of the car. Primarily do in car just to easily pull out after the person. But yes lidar works in inclement weather and so do police.

2971511
05-12-2009, 01:33 AM
Yes LIDAR/LASER works in the rain, several rain, fog, mist can limit the effective range of the beam, so you might need to be closer on a rainy day than clear day,

Shooting thru a windhsield or even a side window can limit the distance as well. I usually either:

1. stand outside the car, or
2. Park perpendicular to traffic and have the side window rolled down.

DACP
05-12-2009, 08:12 AM
Need to ask Monty, he can explain the in's and out's of the thing better then any one I know. :cool:

onetxguy
05-12-2009, 10:32 AM
Okay, i gotta ask a follow-up question

Why is the officer standing OUT in the rain? Does he not have a car he could sit in to lidar traffic? If according to the manufacture clam it should work spiffy right through windsheilds

Was he just standing on the side of the road with no car? I dont see how that would be an effective way to catch speeders....less he can run really really fast ^^

lol im sorry but this just doesnt seem to add up to me. Any explanation on why you would be getting soaked standing outside of your car popping speeders when you can do it just as easily inside the car

Thanks for the response. I would seriously question the accuracy of the unit based on refraction, but I can see that the manufacture has included something in the unit to account for that.

Yes, he was standing in the rain/mist with full rain gear on. This particular area is a high enforcement area where we that drive the area know they are always there. I just assumed that his commanding officer was not happy with him or something and stuck him out there as punishment. :D

I have heard that in Texas the policy is that the officer must have a foot on the ground to use laser. This might be inaccurate, but I do remember hearing that from someone. Perhaps our legislature feels that through the windshield is not as accurate and requires outside, but I dont know.

Again, thanks for the straight answers. My curiosity has now subsided.

onetxguy
05-12-2009, 10:45 AM
As long as you were not the one in the bullseye, why should you care?



I hope I did not hit a nerve. I was just curious. I figured that "Ask A Cop" meant just that.

I was not 'in the bullseye'. I was actually driving slightly over the speed limit following the natural flow of traffic at a safe distance, which I assume is why he did not pull me and the other cars over.

I really like this forum because all responses are on a voluntary basis and questions can be answered or ignored. I am somewhat confused on why some officers feel a need to question a question??? Is there a general distaste or distrust for the public that you serve or are/were you just having a bad day?

Before I get everyone mad I will just stop after one last comment. A considerable amount of advice given on this site is excellent and hopefully people reading take head, but when an officer has a bad day in verbal form it discourages people from asking questions. I know that each of us were taught, early on, that the only dumb questions are the ones left unasked. While there are a lot of trolls out here and even some looking to make you guys look foolish (a task almost impossible to do), there are a lot of good folks who choose to not bother you during your personal time or work time to ask a question that might seem silly (like mine). This forum is a perfect way to ask the question and perhaps, at your convenience, you might answer. No real need to get in an argument over it when you can just choose to ignore it completely.

Again, thanks for your service and keep up the good work.

Highwaylaw
05-12-2009, 11:17 AM
In short:
1. Laser works in the rain
2. Smart cops don't
:)

CityCopDC
05-12-2009, 03:03 PM
Okay, i gotta ask a follow-up question

Why is the officer standing OUT in the rain?

Dangerous and not to smart if you ask me. Its bad enough people slam on their brakes as soon as they see you. Now add in the element of wet roads. Crash reports anyone?

biw371
05-12-2009, 03:11 PM
Dangerous and not to smart if you ask me. Its bad enough people slam on their brakes as soon as they see you. Now add in the element of wet roads. Crash reports anyone?

+1...That's a good reason why I "try" not to stop cars in the rain. Too many people see your lights and slam on the brakes causing rear-end collisions all day long.

I only say "try" because there are just those times where people need to be stopped.

2wheeldep
05-12-2009, 03:11 PM
Some posters come here with really good questions, then there are the posters who want to just bash the police. Some of the questions are really stupid and some are off the wall.

But think about your question for a moment. Would you stand out in the rain with a tool that does not work in the rain, I think not. See how simple that was, you could have answered your own question.

I really don't want to offend you, but most traffic enforcement officers are committed to public safety rain or shine, it's not a punishment for the officer it his choice.

redbird07
05-12-2009, 03:37 PM
Okay, i gotta ask a follow-up question

Why is the officer standing OUT in the rain? Does he not have a car he could sit in to lidar traffic? If according to the manufacture clam it should work spiffy right through windsheilds

Was he just standing on the side of the road with no car? I dont see how that would be an effective way to catch speeders....less he can run really really fast ^^

lol im sorry but this just doesnt seem to add up to me. Any explanation on why you would be getting soaked standing outside of your car popping speeders when you can do it just as easily inside the car

I have to agree with the other officer. He was standing out in the rain because he wanted to. I have a question for you. What do YOU think is the most effective way to catch speeders? Have you ever sat in a patrol car for 10-12 hours a shift? It gets old. Maybe he had been running LIDAR inside his vehicle for a while and decided to stretch his legs. And thats the time the OP's vehicle drove by. I never have gotten soaked during a mist.

In response to the OP's original question.. The Kustom ProLazer III has a setting that can be utilized during inclement weather. It emits a stronger beam over a shorter distance. It still locks onto veh's long before they know I'm there. I think there is a false assumption that these LIDAR detectors work. I have been running LIDAR for 9 years and still only pull over a select few violators. NO, I'm not going to give out my upper speed threshold limit where I begin stopping, but I think I'm pretty generous. Point is, alot of speeders who should get stopped by me, dont. I'm choosing not to stop this car or that car, even though they are at a speed that certainly is fair game to be stopped. I think that these drivers who I choose not to stop think that their radar detector, or the fact that they had their high-beams on, or that they saw me in enough time got them out of being stopped. In most cases it's just the fact that I chose not to stop you. I could write tickets all day long and spend an eternity in court, but YES.....Ive got better things to do with my time.

onetxguy
05-12-2009, 06:58 PM
Thanks to all for the up front responses, even the sarcastic ones:rolleyes:. I did qualify in my original post that it was a silly question. First the question itself assumped that if the officer was using it in the rain then it must have worked, but I also was curious why an officer would be standing in the rain when his automobile is nice and dry. A number of posts answered both questions. I spend a lot of time at a desk and have the ability to get up and walk around the cool dry building to stretch my legs. Of course my job is probably not nearly as fulfilling as all of yours, but I guess that's the pay off.

I appreciate the answer about the weather setting and can see how increasing the beam signal over a shorter distance might reduce the effects of difusion. Again, I asked because I was curious. Heck, for all I know he might have just been standing there looking through the lens to give people a little scare into slowing down. I doubt it, but its a thought.

As for the effectiveness of Lidar/Laser I believe it very effective. I got tagged one day a little over and received an invitation to the local court house. Even though there were circumstances (yes, they exist but I would never be able to convince most here so we wont go there) around my speed at that particular time I figured my number was up and I needed to pay the piper. For all the times I was speeding for no reason getting tagged this once was probably well deserved.

Anyway, thanks again to all of you for answering, your service, and just for being there when we need you (even for the times when we dont ;) ). You all have my deepest respect and appreciation for the job you do. While I will try to keep myself outside of your cross hairs, hopefully if we do have the misfortune to meet in person I hope I dont forget to tell you in person. Just believe that most of us do apprecaite you, even while you are citing us. We are just too embarrased at the moment to say so.

Be safe out there and try to stay dry in the rain.

onetxguy
05-12-2009, 07:15 PM
I have a question for you. What do YOU think is the most effective way to catch speeders? Have you ever sat in a patrol car for 10-12 hours a shift?

#1) Not sure how to answer that. I guess it depends on what your departments goals are. I would hate to start an argument here but I will ask a counter question. Is it your, or your departments goal, to write speeding tickets or to protect the public interest? I ask this question with the following thought in mind. If all traffic is traveling down the road 20 over the posted speed on a clear day open road with no visible hazards in sight, understanding that Texas observes prima facia evidence related to speeding, do you start citing vehicles or recognize that the flow of traffic, even 20 over, is probably a safe traveling speed for that particular stretch of road? Lets get more complicated. The road that I was referring to originally in is thread is a toll road and and the posted speed is 60. A recent traffic survey has been completed and as a result some time in the future the limits will be raised to 70. If I am doing 72, before the new posted limits, would you cite? After all, the recent study claims 70 is a safe speed and +/- 2 would not be considered unsafe if the limit were higher, right? So why is +12 unsafe just because the posting has not taken place?

#2) I have not had to sit in a patrol car stopped for 8-12 hours but I have taken road trips at least that long. It is tough and really gets to certain areas of your body. I stop and stretch my legs on those trips, just like you guys. I choose non rainy areas like convenience stores and such, but that's just the wimp in me. :)

Conclusion. I meant no disrespect by my questions. As I stated I appreciate you guys, even when your job works against my pocket book. I understand that any deletion from my wallet is of my own doing as you are just doing your job. I think the question of what are the real goals are valid. If stopping someone from speeding keeps me, or someone else safer, then they need to be stopped. But when you run the questions abive and put some thought into it....who knows.

SgtScott31
05-12-2009, 07:41 PM
I hope I did not hit a nerve. I was just curious. I figured that "Ask A Cop" meant just that.

I was not 'in the bullseye'. I was actually driving slightly over the speed limit following the natural flow of traffic at a safe distance, which I assume is why he did not pull me and the other cars over.

I really like this forum because all responses are on a voluntary basis and questions can be answered or ignored. I am somewhat confused on why some officers feel a need to question a question??? Is there a general distaste or distrust for the public that you serve or are/were you just having a bad day?

Before I get everyone mad I will just stop after one last comment. A considerable amount of advice given on this site is excellent and hopefully people reading take head, but when an officer has a bad day in verbal form it discourages people from asking questions. I know that each of us were taught, early on, that the only dumb questions are the ones left unasked. While there are a lot of trolls out here and even some looking to make you guys look foolish (a task almost impossible to do), there are a lot of good folks who choose to not bother you during your personal time or work time to ask a question that might seem silly (like mine). This forum is a perfect way to ask the question and perhaps, at your convenience, you might answer. No real need to get in an argument over it when you can just choose to ignore it completely.

Again, thanks for your service and keep up the good work.

My response was to violet_eyez.


Is it your, or your departments goal, to write speeding tickets or to protect the public interest?

One in the same in most cases. Motor vehicle crashes account for more deaths than any other crime.


A recent traffic survey has been completed and as a result some time in the future the limits will be raised to 70. If I am doing 72, before the new posted limits, would you cite? After all, the recent study claims 70 is a safe speed and +/- 2 would not be considered unsafe if the limit were higher, right? So why is +12 unsafe just because the posting has not taken place?

Would I cite? maybe, maybe not, but I'm not going to hound an officer for citing someone going 12 over, regardless of a "recent survey" and the "intention" on posting higher to 70.


If all traffic is traveling down the road 20 over the posted speed on a clear day open road with no visible hazards in sight, understanding that Texas observes prima facia evidence related to speeding, do you start citing vehicles or recognize that the flow of traffic, even 20 over, is probably a safe traveling speed for that particular stretch of road?

Done everyday, though not to the circumstances you indicate. We know most people do 5 - 10 mph over the posted limit, specifically on highways and/or interstates. Most officers set a certain speed before they stop. Some are more conservative than others, but those that are more strict are not necessarily aholes. If the speeds need to be changed, then people in the respective jurisdiction need to go through the proper channels to get the posted limit raised/lowered.

2wheeldep
05-12-2009, 10:08 PM
Some states I've driven in have a 70 mph posted speed limit. I've talked to officers from one of those states and guess what their tolerances for over the limit is not as great. An officer from Az told me their speed limits are "fast enough".

The powers to be already know that people in general drive 10-15 miles over the posted limit, that is why some states will never bump up their speed limits.

I could careless if the speeds on the open highways are put up to 70 mph. I'll still write you at 80 plus, nothing will change for me.

onetxguy
05-13-2009, 12:06 AM
You guys are awesome. Great answers showing common sense, compasion, and intelligence. Not that I expected any less but it is nice to have a forum like this to show all just where you guys stand and that you do understand the public you serve.

violet_eyez
05-13-2009, 12:34 AM
I have a question for you. What do YOU think is the most effective way to catch speeders? Have you ever sat in a patrol car for 10-12 hours a shift?

Depends on your definition of a patrol car, I have sat in a hunk of metal thats falling apart when i worked for the department of corrections driving in a circle around the prison at 20mph for 12 hours with no break. I was patrolling the perimeter and it was a vehicle. Does it qualify?

As for most effective ways to catch speeders that is not a question i would be qualified to answer. I do however have a good understanding of physics and am pretty sure when roads get wet, especially just a fine mist or light rain there is less friction and less traction between rubber and asphalt. therefore i would believe it would be more dangerous to be standing on the side of the road than sitting in a vehicle. Not to mention that most find the rain unpleasant and would rather be under cover during rain if they have a choice. However i do say most. I agree that deciding to stretch your legs even in the rain can be beneficial but that is not information i have if that is what the officer is doing, for all I or anyone else knows (excluding the officer in question) he could of been standing in that one spot for the entire shift

I hope this has answered your question, Sir.

redbird07
05-13-2009, 10:11 PM
#1) Not sure how to answer that. I guess it depends on what your departments goals are. I would hate to start an argument here but I will ask a counter question. Is it your, or your departments goal, to write speeding tickets or to protect the public interest? I ask this question with the following thought in mind. If all traffic is traveling down the road 20 over the posted speed on a clear day open road with no visible hazards in sight, understanding that Texas observes prima facia evidence related to speeding, do you start citing vehicles or recognize that the flow of traffic, even 20 over, is probably a safe traveling speed for that particular stretch of road? Lets get more complicated. The road that I was referring to originally in is thread is a toll road and and the posted speed is 60. A recent traffic survey has been completed and as a result some time in the future the limits will be raised to 70. If I am doing 72, before the new posted limits, would you cite? After all, the recent study claims 70 is a safe speed and +/- 2 would not be considered unsafe if the limit were higher, right? So why is +12 unsafe just because the posting has not taken place?

#2) I have not had to sit in a patrol car stopped for 8-12 hours but I have taken road trips at least that long. It is tough and really gets to certain areas of your body. I stop and stretch my legs on those trips, just like you guys. I choose non rainy areas like convenience stores and such, but that's just the wimp in me. :)

Conclusion. I meant no disrespect by my questions. As I stated I appreciate you guys, even when your job works against my pocket book. I understand that any deletion from my wallet is of my own doing as you are just doing your job. I think the question of what are the real goals are valid. If stopping someone from speeding keeps me, or someone else safer, then they need to be stopped. But when you run the questions abive and put some thought into it....who knows.

Lets keep the response I gave in it's context. The entire response was....

"What do YOU think is the most effective way to catch speeders? Have you ever sat in a patrol car for 10-12 hours a shift? It gets old. Maybe he had been running LIDAR inside his vehicle for a while and decided to stretch his legs. And thats the time the OP's vehicle drove by."

My point was that he possibly got out of his vehicle momentarily to stretch his legs, hence the unusual tactic of running LIDAR in the rain and getting wet. Wasnt trying to but your chops, just offer a possible explanation. I usually dont run traffic in the rain due to safety issues, but I mostly do run LIDAR from my car. I occasionally step outside to stretch legs. I hope we answered your questions. Thats the main thing.

As for the ticket writing question, I stop for all amounts of speed over the limit, but there is a speed where I pretty much cite no matter what the reason (emergencie excluded). I run LIDAR to protect the public,to try to deter speeding, and to look for bigger things. I work in an urban area so 20 over is going to almost always get you a ticket.