License Plate Capture Camera Basics?

[mirak 0]

Here's the situation. Our neighborhood has two entrances. There are large stone monuments (4 in total) flanking each side of each entrance. These monuments actually have cutouts for security cams that were never installed, but I presume the niches are least wired for electric.

 

Importantly, these entrances are not very well lit.

 

We want to record vehicles as they enter and exit so that we can go back and review if there is a crime, etc.

 

I think a motion activated camera system that simply captures high quality still photos is going to be better suited to our needs than a video system? if we've got a picture of the back of each vehicle as they enter and front of each vehicle as they leave, that would be very helpful and we wouldn't need a complicated DVR setup - just record locally to SD cards. We'd just be checking time_stamped photos around the time of the incident.

 

But it needs to be good enough quality to read license plates from 40-50 feet and probably have some sort of flash to work well at night. Is this feasible? What are best products for this sort of solution?

[mirak 0]

The goal by the way is a simple cost effective system where we don't need a costly remote internet setup to review hours of video we don't really need. The thinking is that if we have an incident, we pull a card and review the pictures.

[Blinkenlights 0]

Are you able to control traffic with gates, stop arms or stop signs? Ideally, if you can get the traffic to stop at a well lit location to have their license plate's picture taken, that would be ideal for getting the best quality footage or stills without any footage that you don't want.

 

From someone who routinely catches people in suspicious vehicles doing naughty things, my advice would be to get not only stills of the license plate but also of the entire vehicle and any occupants. Why? Because a lot of n'er-do-wells do not have license plates on their cars, stolen tags or stolen cars or the ubiquitous "tag applied for" written on a piece of cardboard.

 

Really, what you want is the best possible description of the vehicles and their occupants. If something happens in your neighborhood, being able to provide descriptions of the vehicle occupants is priceless. License plates are of limited value.

 

You have quite a few options as your specs are not particularly challenging unless cars are flying by at highway speeds in the dark. You can capture just stills (but why?) and you can get 3rd party software to log license plates. (Again, you are better off with the complete picture of the vehicle and occupants if possible). And if you're going to be the administrator and the HOA is paying for it, get a network camera that you can monitor remotely.

[Sawbones 0]

If the area isn't well-lit, you're going to need IR to light up the plate, and a camera with a long-pass filter. The filter is to block visible light, and transmit the longer-wavelength IR. This will prevent headlights and tail-lights from totally blooming out the image, but ensure transmission of the IR light bouncing off the plate.

 

Since the vehicles are moving, you're going to need something with a fast shutter speed to minimize motion blur... which means you're going to need quite a bit of IR light to ensure adequate return from the moving plate (because remember... fast shutter speed means the imager only gathers light for a VERY short time, requiring more light to produce a usable image). Consider an IP camera with shutter-speed adjustable in software.

 

I'd recommend a large panel illuminator, with a narrow beam angle for better range. You don't want wide-angle here. Raytec, Samsung, or something similar. Avoid going cheap on this... you need quality illumination, and lots of it. Get something that advertises at least a 150-foot range.

 

And consider that you need not only the plate, but the overall scene, requiring two cameras at each entrance (unless you use something with two imagers, like Mobotix). A license-plate camera with a Long-Pass Filter won't see much else besides the plate, so you need ANOTHER camera to show the overall scene (and vehicle type/color/etc). Also, without visible light, you won't be able to determine vehicle color (because IR only produces a black-and-white image)... so consider some normal flood-lights or overhead lights.

 

Also, something that slows the vehicle down will be a HUGE help. Even a low-height "speed hump," located right in the area-of-interest will prolong the time the vehicle stays in the camera frame, and increase your odds of getting a usable image.

 

If you have power, but no internet connectivity at the entrance, you could always record any images/video on an internal SD card (provided the camera supports such). Then attach your IP camera to a wireless access point installed at each entrance, and access the camera memory via wifi (with a laptop) if you ever have an incident. Remote access is nice, but you could make do with local wifi capability.