LPR for speeds up 100kmh

[moviefan]

Hi i am a newbie and am looking to get an LPR camera for my T intersection road. 1 shed is only 3 meters off the road and is about 3 meters high so I can point the camera down to get plate numbers the speed of this road is 100km. the other shed is about 4 meters off the road but just over 2.5 high and because of the T a vehicle has to slow for the corner which is about 40 meters away so they have slowed to about 50kmh by then which cameras would you suggest and could i put a dahua with a hik-vision nvr or vice versa hik-vision with a dahua

I haven't yet decided on getting a Dahua or Hik-vision nvr as it depends on what camera will work at this speed
cheers

 

[wittaj]

Do you want to manually visually read the plates on the screen as opposed to the camera itself reading and logging? That makes a difference on which camera to recommend.

It comes down to three parameters - optical zoom, shutter speed, and angle.

You need enough optical zoom to make the plate as large as possible in the field of view. Ideally, the field of view should have the vehicle and not much else, so it isn't an overview camera.

You need to try to get as much as a straight on angle as possible, which is why most of us get a high powered optical zoom so we can point it down the street and "flatten" the angle.

You need to run the camera at a fast shutter in order to capture the plate. Shutter speed is more important than FPS.

At night, we have to run a very fast shutter speed (1/2,000) and in B/W with IR and the image will be black. All you will see are head/tail lights and the plate, so it serves the only purpose of reading plates and is not an overview camera. Some people can get away with color if they have enough street lights, but most of us cannot. Here is a representative sample of plates I get at night of vehicles traveling about 45MPH at 175 feet from my 2MP camera (that is all that is needed for plates):



You may need to run a faster shutter for your speed, but it is certainly possible.

 

[samplenhold]

If you are going to use an NVR, use the same brand as the cameras that you buy.

100KPH is about 62mph, so that is quite fast. As @wittaj stated, it will be important to get as close to head on as possible. Try using a DSLR or a smart phone and video some cars passing by. Can you stop the video and get a look at the plates?

I live on a T intersection and have two cams running. But the top speeds here would be in the 50kph and slower. See my thread on that install:

LPR Case Study: Scoping, Planning, Proof of Concept, Installation, & Results

Introduction This thread is about my journey into LPR (License Plate Recognition) after having about 18 months of experience with IP cams and having quite a bit of my system finished. I am not an expert on LPR, or IP cameras either. But I have spent a lot of time working with my system and...

ipcamtalk.com

 

[moviefan]

Do you want to manually visually read the plates on the screen as opposed to the camera itself reading and logging? That makes a difference on which camera to recommend.

It comes down to three parameters - optical zoom, shutter speed, and angle.

You need enough optical zoom to make the plate as large as possible in the field of view. Ideally, the field of view should have the vehicle and not much else, so it isn't an overview camera.

You need to try to get as much as a straight on angle as possible, which is why most of us get a high powered optical zoom so we can point it down the street and "flatten" the angle.

You need to run the camera at a fast shutter in order to capture the plate. Shutter speed is more important than FPS.

At night, we have to run a very fast shutter speed (1/2,000) and in B/W with IR and the image will be black. All you will see are head/tail lights and the plate, so it serves the only purpose of reading plates and is not an overview camera. Some people can get away with color if they have enough street lights, but most of us cannot. Here is a representative sample of plates I get at night of vehicles traveling about 45MPH at 175 feet from my 2MP camera (that is all that is needed for plates):

View attachment 112204

You may need to run a faster shutter for your speed, but it is certainly possible.

Getting a flat angle is no issue as i can install them lower to the ground to flatten the angle. I hadn't thought much whether to let the camera log the plate or read it from the screen. Reading it from the screen means i have to spend more time looking at a monitor so if the camera logged it to the nvr would be better all round

 

[bigredfish]

Actually i dont think the speed will be too much problem with a simple 5241Z-12 or even a 5442-Z4

Here's a grab from a car going about 45-50mph at a 30+ degree angle. The car is traveling left to right on the main connector street our street intersects. The camera is actually focused closer to catch vehicles exiting our neighborhood. Distance to capture is about 60-75ft


View attachment HOA Entr_ch1_20201115213551_20201115213602.mp4

 

[f1restarter]

How fast moving cars are you guys able to capture with 1/2000 shutter speed?

I am currently planning my LPR install; The road where I live is sparsely populated, but it is a straight road with a 40kph speed limit due to it beeing a school road and several driveways entering straight into it. We have a lot of problem with speeders here.

I had a madman drive by earlier this year, and with my 4K-t camera pointed perpendicular to the road, I was able to roughly calculate his speed by skipping frame by frame (That cam runs 15fps) and see how far the car moved per frame. Now this is not by any means very accurate, but he was doing between 140 and 160kph (close to 100MPH)

Would a 5241e-z12e be able to capture a plate of a car going that fast? And with my proposed install location it will be about horizontal 30° and at license plate height. Distance about 33meters or 100feet

 

[bigredfish]

My best was inadvertent, captured with a 6 series PTZ at approx 55-60mph running 1/2000 at approx 70ft,at a not so great angle..



So just wild ass guessing, using a Z12, at a better angle, less than say 75ft, running 1/4000? I think its doable

 

[bigredfish]

Duh, didnt see this was an old thread I'd already posted same in. sorry

 

[f1restarter]

Duh, didnt see tuis was an old thread Id already posted same in. sorry

I was searching the forum for this subject in case it had been answered earlier, and this thread was the most relevant I could find, so instead of starting a new thread I "hijacked" this...
So @bigredfish , you think I would have to run 1/4000 shutter to capture cars/bikes going 100mph? 99% are not driving crazy like that, but I would really like to be able to catch those plates...

 

[bigredfish]

at 100ft yeah thats a good starting point I think.
anything past 30 degrees is where I've always said it gets dicey.

With enough IR (I'm running a 200ft rated external IR on that scene) it should be possible. Most folks misjudge how far and how powerfiul IR they need. I always cut every rating in 1/2 for starters