Poor IR contrast in new Tennessee license plates

[wittaj]

So a friend of mine got a set of the new plates and then someone did a hit-n-run on the road and totaled his car and banged him up pretty good, so he pulled the plate off and I have been playing with it.

I know TN plates seem to be the worse offender and I haven't had one come by yet, but I found these two options to work with other states, so see if you could test it with a TN plate.

1. Drop the gamma down to 5 and blast it with IR. Brightness was at 35 and contrast was at 80
2. Get the camera within a couple feet of the street and run gamma around 10-20

The problems with these are obviously to get a focused beam for the distance a Z12E can reach, you will be paying more than the Z12E for that IR gun. The other option of getting it close to the street works well for someone that has mailbox at the street on their property and can run the cable to it.

Plus in either case, it is a much tighter window to get the plate. Under more normal setup with cars going right to left and left to right, I could see the plate from the time they entered the field of view to when they exited. At this low gamma I am only seeing the plate for half the field of view.

The benefit though is any cars parked on the street are not now triggering OpenALPR all night LOL.

 

[Smilingreen]

So a friend of mine got a set of the new plates and then someone did a hit-n-run on the road and totaled his car and banged him up pretty good, so he pulled the plate off and I have been playing with it.

I know TN plates seem to be the worse offender and I haven't had one come by yet, but I found these two options to work with other states, so see if you could test it with a TN plate.

1. Drop the gamma down to 5 and blast it with IR. Brightness was at 35 and contrast was at 80
2. Get the camera within a couple feet of the street and run gamma around 10-20

The problems with these are obviously to get a focused beam for the distance a Z12E can reach, you will be paying more than the Z12E for that IR gun. The other option of getting it close to the street works well for someone that has mailbox at the street on their property and can run the cable to it.

Plus in either case, it is a much tighter window to get the plate. Under more normal setup with cars going right to left and left to right, I could see the plate from the time they entered the field of view to when they exited. At this low gamma I am only seeing the plate for half the field of view.

The benefit though is any cars parked on the street are not now triggering OpenALPR all night LOL.

I would help, but any cars are a 1/3 of a mile away.....behind a hill.....and the woods........not to mention, I don't have any LPR cameras. All three of our vehicles kept the white 3M type plates this year. We didn't get up-graded to the new midnight blue plates. They must have had issues with converting handi-capped plates over to the new plates.

 

[erkme73]

Same with emergency and personalized tags as well. Mine are all still white.

 

[wittaj]

As a follow-up to my post 261 regarding these new 3M flat printed plates, here are some examples.

Now most are familiar with my representative sample I post when people ask about LPR. This is the typical stamped plate with raised lettering.

Here is a representative sample of the stamped plates I get at night with a 1/2,000 shutter and 8 FPS of vehicles traveling about 45MPH at 175 feet from my Z12E that is on the 2nd story soffit, Camera is 35 feet above street at this location with no street lights or house lights on, just the infrared from the camera:




As the title of this thread indicates, the new 3M process of printed plates results in poor contrast of a certain blue with infrared.

Here is a sample of a new plate with my Z12E at 175 feet away:



As you can see, the plate is washed out. I have tried everything and just cannot get a consistent plate with new printed plate.

So I was playing around with my old 2MP Loryta IPC-HDW5231R-ZE 2MP varifocal that was sitting around gathering dust since I had been replaced it with the 5442-ZE

If you are able to get the camera within 20 feet or so of the plate, you stand a much better chance. Here is the washed out plate above from a camera much closer:



In order to make this happen, the settings are way off what we normally use. I dropped the gamma down to 5 (since bumped up to 15), with brightness at 35 and contrast at 80, with gamma at 20.

I think the TN plates are probably using the worse shade of blue possible and I don't know if this will work for TN plates, but for anyone that is starting to experience these new 3M plates, I suggest finding someone that has them (if you don't) and go to the basement or the garage and set up a camera on one end and the plate on the other. We already know the shutter will be 1/1000 or 1/2000 so start with that and turn the lights off and play with the parameters until you can start to see the plate. That will get you a little closer to start with once you have someone start driving by LOL.

 

[samplenhold]

If you are able to get the camera within 20 feet or so of the plate, you stand a much better chance. Here is the washed out plate above from a camera much closer:

So the question becomes, is it that getting the cam very close, and therefore the IR illuminators close, the reason the 5231R-ZE works, or is it that the 5231R-ZE has a different IR affinity than the 5241 Z12E?

I wonder if getting the 5241 Z12E closer would work just as well?

 

[wittaj]

So the question becomes, is it that getting the cam very close, and therefore the IR illuminators close, the reason the 5231R-ZE works, or is it that the 5231R-ZE has a different IR affinity than the 5241 Z12E?

I wonder if getting the 5241 Z12E closer would work just as well?

Great question.

IIRC I thought @wtimothyholman tested with a PTZ and the PTZ had better success than the Z12E - do I recall that correctly? So if so, maybe the 5231 has a different affinity.

I would think the Z12E closer would probably help as well.

I think the biggest issue with the new plates and the longer optical zoom of the Z12E is that at the end of the day, the sensor is still small and I think the distance compounds the problem with this questionable 3M color.

@biggen has one of those expensive, concentrated IR Axton units - are you seeing any of these new plates and how is yours handling it?

 

[erkme73]

Thank you guys for continuing to test these horrible tags. I get excited everytime a notification for a new post on this thread arrives.

 

[DLONG2]

Yes, I am hoping for a general solution for consistent and quality plate captures using those white light strobes.

 

[samplenhold]

I am wondering about IR intensity and if TX has gone to a similar plate.

For the last several weeks, I have had this one pickup come by at night taking a left at the intersection. The plate is totally washed out at the closest distances and then becomes visible as the distance increases. It is still a white plate with black letters, so I do ultimately get a good read. This is the ONLY one that it happens to. At first I thought it was just at the right angle to reflect back at the cam, but I get lots of pickups and you would think that one other would be at the same angle. Plus, this happens EVERY time with this particular truck.

Here is the washed-out plate:


Good read at more distance:


This is from the intersection cam to show the whole truck:

 

[MikeLud1]

I am wondering about IR intensity and if TX has gone to a similar plate.

For the last several weeks, I have had this one pickup come by at night taking a left at the intersection. The plate is totally washed out at the closest distances and then becomes visible as the distance increases. It is still a white plate with black letters, so I do ultimately get a good read. This is the ONLY one that it happens to. At first I thought it was just at the right angle to reflect back at the cam, but I get lots of pickups and you would think that one other would be at the same angle. Plus, this happens EVERY time with this particular truck.

Here is the washed-out plate:
View attachment 148637

Good read at more distance:
View attachment 148635

This is from the intersection cam to show the whole truck:
View attachment 148634

I Just ran your images using my new ALPR B/W no issues reading it color some issues

 

[biggen]

I wish I had a TN plate I could test with for my Axton IR unit. I only have a handful of them come through the neighborhood from time to time but I don't have any record of one at night.

 

[jmjm222]

Has anyone come up with an actual solution to this?

Are the pricier/better cameras like Hiikvision able to workaround the issue?

Or have all these new plates flooding the streets out there basically ruined LPR for home use? I was about to start building a setup but if it won't work at night with half the plates out there, there's no point.

 

[wittaj]

Has anyone come up with an actual solution to this?

Are the pricier/better cameras like Hiikvision able to workaround the issue?

Or have all these new plates flooding the streets out there basically ruined LPR for home use? I was about to start building a setup but if it won't work at night with half the plates out there, there's no point.

Have you read thru the thread?

A better and pricier camera will not work.

It comes down to basic physics. The shade of blue being used cannot be seen with infrared light. The OP of this thread has tested the different IR available and demonstrated/explained it in this thread.

You need either a lot of white light or get the camera as close as possible as I have shown in Post #264 or hope your state doesn't use the blue ink...

@wtimothyholman has been working on a possible pulsed white light solution that hopefully doesn't blind drivers, but flooding in his basement has delayed that attempt.

 

[jmjm222]

Have you read thru the thread?

A better and pricier camera will not work.

It comes down to basic physics. The shade of blue being used cannot be seen with infrared light. The OP of this thread has tested the different IR available and demonstrated/explained it in this thread.

You need either a lot of white light or get the camera as close as possible as I have shown in Post #264 or hope your state doesn't use the blue ink...

@wtimothyholman has been working on a possible pulsed white light solution that hopefully doesn't blind drivers, but flooding in his basement has delayed that attempt.

I have. I just find it hard to believe none of the camera manufacturers have come up with a solution? This basically renders LPR systems worthless in the US. I imagine everyone here plans on selling theirs?

Would a color night camera with a higher resolution and zoom offer any kind of workaround here?

 

[jmjm222]

It looks like the Genetec SharpV may have addresses the issue: AutoVu SharpV

"
Illuminator
Pulsed LED illuminator for effective use in
0 lux (total darkness) environments
940nm, 850nm, 740nm, and 590nm illumination
wavelengths available"

 

[wittaj]

I have. I just find it hard to believe none of the camera manufacturers have come up with a solution? This basically renders LPR systems worthless in the US. I imagine everyone here plans on selling theirs?

Would a color night camera with a higher resolution and zoom offer any kind of workaround here?

Again, it has nothing to do with camera manufacturers as they cannot defy the law of physics and light characteristics.

Some of the LPR companies have claimed they have created algorithms to overcome it, but my friends in law enforcement that have received the new firmware has said it is useless.

The infrared cannot see that color of blue or has a very difficult time with it at distance. As I have shown, if you can get the camera closer, you stand a better chance.

I don't think folks here will get rid of their systems as it will take a while for a state to completely turnover every plate, and at some point the police will hopefully get enough pull to get the plate changed as their in-car LPR is useless as well with these new plates.

A color night camera would not work as it comes down to running a fast shutter speed. We have to run fast shutter speeds that make the image black except for the plate and head/tail lights as have been shown throughout this thread and others. And the piddly white light on the full color camera would be useless at any distance.

Plus there is no color night camera (on the 1/1.2" sensor) on the market that is varifocal and the ones that claim to be varifocal full color cameras are on smaller sensors and would perform poorly.

You would need ideal conditions like @samplenhold above where there are lots of streetlights and cars come to a stop sign that you can slow the shutter down.

 

[wittaj]

It looks like the Genetec SharpV may have addresses the issue: AutoVu SharpV

"
Illuminator
Pulsed LED illuminator for effective use in
0 lux (total darkness) environments
940nm, 850nm, 740nm, and 590nm illumination
wavelengths available"

What makes you think that camera addresses the issue - are you a vendor for that camera LOL?

The IR versions from 740nm up have been tested here and do not work with that color of blue, so that rules out 3 of the available options right there.

Let me make this clear - it is the infrared that these plates with blue ink have trouble with. If you have enough white visible light, then the camera we use can read the plate. Or if your state doesn't use blue, it is not an issue.

590nm gets into the visible light spectrum, which gets back to what I said that if you have enough white light focused on the plate, then yeah you can run in color and get the plate.

Most of us don't have that kind of light.

The 590nm may work and that is what @wtimothyholman will be testing, but in some subdivisions, especially those that do not have streetlights, this pulsating white light would be a major turnoff and distraction. It works well in retail settings and toll roads where there are lots of ambient lights around so this pulsating light gets "lost" in the eyes of the driver. A dark subdivision is another story.

Plus the MSRP of Genetec's Sharp camera and included accessories totals ~$7,000, plus another ~$2,000 in licensing costs for AutoVu server, totaling about $9,000 for a single camera system....I don't think most here will pay that....and this is why we hope the @wtimothyholman solution to make one works! But again it might be problematic in some subdivisions.

 

[wtimothyholman]

Have you read thru the thread?

A better and pricier camera will not work.

It comes down to basic physics. The shade of blue being used cannot be seen with infrared light. The OP of this thread has tested the different IR available and demonstrated/explained it in this thread.

You need either a lot of white light or get the camera as close as possible as I have shown in Post #264 or hope your state doesn't use the blue ink...

@wtimothyholman has been working on a possible pulsed white light solution that hopefully doesn't blind drivers, but flooding in his basement has delayed that attempt.

A note to all: my workshop has just gotten put back together after the flooding damage was repaired. I should have some test results with my prototype white light illuminator within a couple of weeks. Also, I'm not sure if I'll need to pulse the LED light, but if I do it will be at a minimum of 50 Hz, well above the frequency where it would be distracting to drivers.

Furthermore, I'm using an LED with a color temperature similar to what you'd see on most outdoor lights: not harsh white light, but more towards the yellow end of the spectrum, so it blends in with residential lighting.

 

[samplenhold]

This basically renders LPR systems worthless in the US. I imagine everyone here plans on selling theirs?

Wow, you really do not understand the situation. Some of the newer plates in a state or two have issues with IR reflection in the wavelengths used for most LPR cams. That does not 'render LPR systems worthless in the US'. I have no issue here in TX. I certainly will NOT be selling mine.

 

[erkme73]

I don't think folks here will get rid of their systems as it will take a while for a state to completely turnover every plate, and at some point the police will hopefully get enough pull to get the plate changed as their in-car LPR is useless as well with these new plates.

I can't speak to the rest of the state, but in my county in middle-TN, the turnover is complete. The only "old-style" (black on white) plates are vanity, emergency, or commercial. All personal vehicle standard tags are now white on blue.

My camera is about 25' from the centerline of the road where the tags go by. Here's what I get:

Old style tag:


New plate:


No matter how reflective the tag may be, having it covered with gravel road dust can make it unreadable. Here's my tag, which is the old style (emergency):