Funny until I read the last part of your sentence, I had Roof gutters in mind, thinking they must hang down a lot to get in the way of the CAM, LOL...
New to LPR? Considerations Before You Begin
- Thread starter samplenhold
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Weird. Went out a couple nights ago and sat in the road focusing on my plate with 1/1000 exposure, 50 HLC. Everything looked great. But capturing way less now with blurry plates unless they are fully stopped at the stop sign. Reducing FPS the cause? I.e, wouldn't more frames per second give a better chance of capturing plates?
Figure it's that, or moving from 1/500 to 1/1000. Maybe given the size of the road I'm capturing 1/500 works better for whatever reason?
Figure it's that, or moving from 1/500 to 1/1000. Maybe given the size of the road I'm capturing 1/500 works better for whatever reason?
bigredfish
Known around here
Going to a faster shutter will make it a bit darker, but not more blurry. Opposite actually.
And FPS has nothing to do with focus. I argue more FPS helps in LPR just because you get more frames to pick from to get the best image, but this isn’t your problem.
Did you change anything else?
What are your DNR settings?
Is the plate well lit but blurry?
And FPS has nothing to do with focus. I argue more FPS helps in LPR just because you get more frames to pick from to get the best image, but this isn’t your problem.
Did you change anything else?
What are your DNR settings?
Is the plate well lit but blurry?
Yep FPS has nothing to do with blurry....well in some instances if you are maxing out all the specs in the camera then a higher FPS can result in blurry images but that is because of the camera not being able to keep up with the shutter speed and other parameters and results indirectly in blurry images.
Did you write down the focus number and are sure that it is the same focus number now? You could have set it a few nights ago and now it focused on something else and the focus number is different (we see that here all the time).
Post pics of your other settings, along with the zoom focus number (how far zoomed in is it). As this thread shows, things like gamma, brightness, contrast, etc. impact focus as well (which most people would not think it would).
ipcamtalk.com
Did you write down the focus number and are sure that it is the same focus number now? You could have set it a few nights ago and now it focused on something else and the focus number is different (we see that here all the time).
Post pics of your other settings, along with the zoom focus number (how far zoomed in is it). As this thread shows, things like gamma, brightness, contrast, etc. impact focus as well (which most people would not think it would).
which setting causes 5241E-Z12E blur with even slow motion?
The picture below has been cropped but otherwise has not been edited, even though it looks like someone used photo-editing software to blur the license plate on the left. I can't control the cars that drive by, so I manually put an old license plate and circular reflector on the right side of...
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bigredfish
Known around here
Agree sounds like a focus issue
I run two 5241 Z12's and two 5231 Z12's at 30 FPS, with IVS and MD at 8192 bitrate, and get good captures from 40-120 ft
I run two 5241 Z12's and two 5231 Z12's at 30 FPS, with IVS and MD at 8192 bitrate, and get good captures from 40-120 ft
And on the other end of the FPS spectrum LOL:
Here is a representative sample of plates I get at night with a 1/2,000 shutter and 8 FPS of vehicles traveling about 30MPH 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:
The vehicles are in and out of my field of view around 0.5 seconds, so I am getting 4 or so frames per plate and get them all, except for the rusty or dirty or bent or temp or any other plate that wouldn't be captured anyway.
I run it low because I use OpenALPR and that thing is a resource hog and 30FPS would bring my system to its knees. 15FPS is even a struggle for it. As long as I get the plate, that is all I care about.
Here is a representative sample of plates I get at night with a 1/2,000 shutter and 8 FPS of vehicles traveling about 30MPH 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:
The vehicles are in and out of my field of view around 0.5 seconds, so I am getting 4 or so frames per plate and get them all, except for the rusty or dirty or bent or temp or any other plate that wouldn't be captured anyway.
I run it low because I use OpenALPR and that thing is a resource hog and 30FPS would bring my system to its knees. 15FPS is even a struggle for it. As long as I get the plate, that is all I care about.
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Shots of settings below. Focus is what I set it to (and what I set it in the Dahua utility to)..
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Anything stand out in the above? One issue I noticed is I had a mismatch on frame rate between BI and the cam so not sure if that was causing the blurring on moving plates (though they are not moving very fast there).
No those seem reasonable.
I still think it is a focus issue and you set it at one number and a couple days later it is off a few.
OR you are zoomed in so tight that the focus depth is so tight that anything before or after that is blurry. Maybe try bring the iris down as a higher iris setting can shrink the available area of focus.
I still think it is a focus issue and you set it at one number and a couple days later it is off a few.
OR you are zoomed in so tight that the focus depth is so tight that anything before or after that is blurry. Maybe try bring the iris down as a higher iris setting can shrink the available area of focus.
Just getting back from an overseas trip. Here's an example of the blurriness I'm referring to other than when the car is completely stopped (even then not as focused so will need to work on that).
OK a lot going on there and I don't think you provided yet how zoomed in it is, but the closer you get to max zoom, the smaller the focus area is.
The blurry when the car first enters is due to being off-center of the infrared. Infrared works be reflecting back, so when it off the center, it has trouble reflecting back. That and that isn't the focus point I suspect.
Now the plate starts to get readable as it gets more centered and closer.
This is probably the cleanest shot.
I suggest you have someone go out and stop at say those three locations and then focus and you will see the focus number will be different for each one.
You then need to decide which one is the one you want to get the clean focus or average the focus numbers of the 3 spots and then recognize it won't be clean and crisp everywhere, but may be readable from more distances.
Even with my tight image where a car is in and out of the frame in under 0.5 seconds, as it gets close to and outside the red box, it gets blurry. The focus numbers starting top right corner to center to bottom left corner were different by 10 steps. So I went with the clear focus step in the center and can still read the plates outside of that, but they will be a little blurry.
bigredfish
Known around here
Is the B521R-Z12E-S2 still the king for LPR? Debating ordering one before sale ends to dip my feet in the waters with LPR.
Here are some quick specs for the situation:
Speed limit is 25 MPH but average is 35-40 and I've had cars racing on my street which is why thinking of an LPR (hoping to catch the kids speeding).
Thanks in advance.
Here are some quick specs for the situation:
- House is about 80-90 feet from the street depending where I mount the camera
- Street width is about 4 cars wide (side by side). I can't get the exact width since I'm not home and won't be before the sale ends. Basically you can have 2 cars parked on either side and still have 2 cars pass cleanly between them. Hope that makes sense.
Speed limit is 25 MPH but average is 35-40 and I've had cars racing on my street which is why thinking of an LPR (hoping to catch the kids speeding).
Thanks in advance.
The Z12E is still the king, but if the distance is shorter (40-60 feet), then the new chipset Z4E Isa viable candidate.
Just keep in mind that depending on your angle, getting two lanes from one camera can sometimes be problematic.
Just keep in mind that depending on your angle, getting two lanes from one camera can sometimes be problematic.
bigredfish
Known around here
Yeah the 80-90 feet is the distance at a right angle to the street (i.e.: driveway length). So the distance of the camera (hypotenuse) is is obviously going to be a lot more to get the correct angle which is the part I'm worried about. Cars are supposed to have front plates here but many do not. I was hoping to just need 2 cameras so can try to get the front and back of the car which would mean each camera capture both sides of traffic.
jimnycricket65
n3wb
An awesome job.
Any update to the system + camera?
I presume you need one of those DVR/Brain units with the POE capabilities.
jimnycricket65
n3wb
I just want the simplest system that will capture license plates going through our street
. I realized after installing many, many house cams none of them would work for what I wanted done - I placed those cams in the mailbox with a hole bored for the lense. None of them are good enough. It won't even pick up my own car's plate that is about two or three cars away. Dahua HFW5241E-Z12E seem to be a good cam. I presume I will need one of the "server/Brain" DVRs to power this camera up.I just want the simplest system that will capture license plates going through our street
A Z12E on the mailbox would be overkill.
A 54IR-ZE (5442-ZE) would be the better choice.
You could run it with just the SD card, although it wouldn't be recommended for long term reliability.
When I first got into LPR, I did it with just the Z12E and an SD card. But I quickly added an NVR for longer video retention and to record 24/7 because recording on motion would miss some plates.
Now keep in mind, you can't run the camera on default/auto settings. You need a lot faster shutter. At night it will probably be all black except for the plate.
I suspect the cameras you put in the mailbox were the typical 2.8 or 3.6mm fixed lens with no ability to set something like shutter speed and the camera honor it.