Red Light Camera alert on parallel streets

 

When I go with the default distance on the Red Light Camera file I get alerts on parallel streets. Each POI file is in separate folders on the SD card. I don't change the name as it comes from here. I have some POI files that are TourGuide, but they are in their own folders. Is there something embedded in the Red Light Camera file that causes this? I am using a Nuvi 265WT.

Might be that....

Might be that the coordinates are such that being on a parallel street makes the unit think the camera is close enough to alert.

Pick one of the lights that do such and then find it in EPE to see where it is.

It's the tour guide setting

It's circumferential. For example, if you set proximity alerts for 500 feet, in Tour Guide mode, that's a 1000 foot diameter circle with you in the middle. That's a whole lotta real estate... The 'normal' proximity alerts are narrow bands about 30-50 feet wide, and the distance you have set them to alert you. This is why parallel streets don't set 'em off.

Hope that helped.

--
Striving to make the NYC Metro area project the best.

Not TourGuide

The Red Light Camera files are not TourGuide, but they still alert on parallel streets

Proximity alerts

The red light camera file should not alert on a parallel street. You didn't say what GPS you are using but that shouldn't make any difference. The file name "RedLight" will set the alert distance based on your speed to give you about 30 seconds of warning but the width of the alert corridor is going to be less than ~100 feet and fixed.

Double check the file name, it should be "Redlight-Cameras.csv". It shouldn't contain any other key words.

Make sure your GPS is set to Degrees, Minutes, Decimal Minutes. My 750's options are in:

Where to? > Coordinates > Format

Select "h ddd mm.mmmm'" and hit ok.

Go to one of the intersections and check it's coordinates against those listed in the file. They should match to within a few hundredths of a minute. If all of the above is as it should be, I'm at a loss.

See Original Message

jackj180 wrote:

The red light camera file should not alert on a parallel street. You didn't say what GPS you are using but that shouldn't make any difference. The file name "RedLight" will set the alert distance based on your speed to give you about 30 seconds of warning but the width of the alert corridor is going to be less than ~100 feet and fixed.

Double check the file name, it should be "Redlight-Cameras.csv". It shouldn't contain any other key words.

Make sure your GPS is set to Degrees, Minutes, Decimal Minutes. My 750's options are in:

Where to? > Coordinates > Format

Select "h ddd mm.mmmm'" and hit ok.

Go to one of the intersections and check it's coordinates against those listed in the file. They should match to within a few hundredths of a minute. If all of the above is as it should be, I'm at a loss.

As I said I am using a Nuvi 265WT and the file name is Redlight-Cameras.csv and was not changed from this site.

Parallel Streets?

I don't believe the alerts are coming from parallel streets, but multiple alerts from the next location ahead and also the next one ahead after that.

The Red Light Camera files are not written for tourguide alerts. You would have to rewrite each line of the file for them to become tourguides. No alert should be given for any location more than 50 feet away from the road to either the left or right side.

The problem probably lies in the default alert distance when using POI Loader in auto, which is 1320 feet, or a quarter mile. When approaching a single camera location ahead you will get audio alerts four times, if you keep going, and additional ones if you stop and go.

The quarter mile alert distance is enough to generate alerts for the next two camera locations ahead if they are less than an eighth of a mile apart. For instance, in Manhattan, New York City, the intersections are a tenth of a mile apart.

To solve the confusion of multiple alerts, I use POI Loader in manual and set the distance to 500 feet for low speed limits such as 25 mph. This gives me one alert at 500 feet and a second just before the intersection. If I usually drove out in the country at 55 mph, I would set the distance to 800 feet. All locations must have the same distance unless you want to sort locations and split the file up into several files, or convert certain files to .gpx, both too cumbersome in my opinion.

The alert distance for the RLC file is not based on speed, but is constant based on your POI Loader settings and whether it is used in auto or manual.

dobs108 smile

Parallel

jjen, are you sure you mean parallel and not perpendicular? I know the alerts are non directional, so when a camera poi is placed at an intersection, it will alert when apporaching that intersection from all 4 directions.

--
Alan - Android Auto, DriveLuxe 51LMT-S, DriveLuxe 50LMTHD, Nuvi 3597LMTHD, Oregon 550T, Nuvi 855, Nuvi 755T, Lowrance Endura Sierra, Bosch Nyon

.

Instead of having us make wild guesses as to the cause of the problem, why don't you give us the coordinates of one or more of the parallel streets and red lights.

Parallel Streets

alandb wrote:

jjen, are you sure you mean parallel and not perpendicular? I know the alerts are non directional, so when a camera poi is placed at an intersection, it will alert when apporaching that intersection from all 4 directions.

The streets are one block over from the streets that have the cameras and headed in the same direction. To me that is parallel. The alerts act as if they were TourGuide files acting in a radius from the way point.

I have seen

situations where if your possible travel direction takes you in the path of a camera and the it's in proximity, the alert will sound. For example: You are approaching an intersection and the right hand turn will take you though a device, the Garmin will sound if in proximity, even though you're going straight. It doesn't know your actions, and it just gives you all options (in my opinion).

--
Striving to make the NYC Metro area project the best.

Can you give us coordinates

?

i'd rather receive these

i'd rather receive these nearby alerts than none at all. if a user is annoyed, he/she can disable it.

Coordinates

32.545110, -97.327400
32.541690, -97.330660
32.534330, -97.336060

Huh?

snail700 wrote:

i'd rather receive these nearby alerts than none at all. if a user is annoyed, he/she can disable it.

Why would someone want to get an alert on a street that has no Red Lights?

Which street?

jjen wrote:

32.545110, -97.327400
32.541690, -97.330660
32.534330, -97.336060

For the first one, which parallel street? The main street is NE Wilshire, so which parallel street? If you are saying you are one one of the four named NE Wilshire, what's the problem? It is notifying you of a camera at the intersection, just because it isn't in your lane isn't the fault of the POI, it's the accuracy of your unit coupled with the accuracy of the point marked. In this case, I would want to know there is a camera there and the lane or lanes would be immaterial.

--
Illiterate? Write for free help.

think two correct and one different

jjen wrote:

32.545110, -97.327400
32.541690, -97.330660
32.534330, -97.336060

I put in one set of your coordinates and found it was Burleson, TX.

I went to the POI file I have (and there have been updates since my last load) and looked for Burleson TX and found 3 sets of coordinates. Two matched to your set and one differed.

Using Google maps I looked at the one that differed and found that yours was the intersection of Hwy 174 (aka Wilshire Blvd) and NW Rebfro St. The POI file coordinates pointed to Hwy 174 and John Jones Dr.

I assume yours is a newer POI Factory file but it seems odd that one of the interections is different.

Parallel Street

Box Car wrote:
jjen wrote:

32.545110, -97.327400
32.541690, -97.330660
32.534330, -97.336060

For the first one, which parallel street? The main street is NE Wilshire, so which parallel street? If you are saying you are one one of the four named NE Wilshire, what's the problem? It is notifying you of a camera at the intersection, just because it isn't in your lane isn't the fault of the POI, it's the accuracy of your unit coupled with the accuracy of the point marked. In this case, I would want to know there is a camera there and the lane or lanes would be immaterial.

The parallel street is SW Johnson Ave. It won't do it during simulation. I just returned a few minutes ago and got the alert, apparently, from 174 and Newton when traveling on SW Johnson Ave. Distance set at 1320 feet. There are 4 cameras on 174.

alerts

I have never noticed this, but what I have noticed is driving over an intersection below you alerts wink

Not much to be done in such a case.. Im clearly within my alert zone wink

Not Parallel

Google Earth shows that Johnson is not exactly parallel with 174, there is an acute angle. At some point when you are driving on Johnson, the camera located at 174 and Newton is in front of you (or up to 50 feet off to the side) even though Johnson does not go there.

If you were navigating a route I think no alert would be given, because the GPSr would know you will be on Johnson.

I predict that if the alert distance is changed from 1320 feet to 700 or 800 feet the problem will not happen again.

dobs108 smile

All Good Coordinates

All jjen's coordinates are in the latest RLC file -

174 & Renfro

174 & Newton

Wilshire & Summercrest

(Wilshire is also known as route 174.)

dobs108

Wilshire & Summercrest is the Problem!

Johnson joins Wilshire (174) right near Wilshire & Summercrest! This is certainly the problem one since that intersection is almost directly ahead of you when driving SW on Johnson. 1320 feet is a very long distance, and that is the problem.

However, I think that even if the alert distance is shortened, Wilshire & Summercrest will still sound an alert at the extreme south end of Johnson.

dobs108 wink

Now with a little more data

You get an alert when traveling N on SW Johnson between Newton & Ellison I'll wager. The cure is to shorten the alert distance. Why it happens when driving and not in simulation is the positional accuracy issue. Your position is accurate to within 30 meters (about 90 - 100 feet) same for the point where the POI is marked. The marking is probably within 20 to 30 feet (7-10 meters) and when added to the calculated position you would be within the 50 - 75 foot wide zone of the alert distance for the camera.

Because Johnson runs at an increasing distance from Wilshire, shortening the alert distance will decrease the probability the slop in positional accuracy will trigger the alert.

--
Illiterate? Write for free help.

I wondering the same

I wondering the same thing,good advice.

--
Sly

Different Interpretation

camerabob wrote:

situations where if your possible travel direction takes you in the path of a camera and the it's in proximity, the alert will sound. For example: You are approaching an intersection and the right hand turn will take you though a device, the Garmin will sound if in proximity, even though you're going straight. It doesn't know your actions, and it just gives you all options (in my opinion).

My observations are consistant with a proximity alert being sounded if the alert is within the distance criteria and within an angle close to your direction of travel (like within 30 degrees of your direction of travel).
Mark