Camera for long range (optical zoom) license plate detection

[sparrowcup]

Hi!

I'm trying to find a camera that can focus on a specific spot/area around 330ft / 100m away from my window (apartment building, 4th floor) for recording license plates coming in and going out.
It does not have to cover a large area, nor do I expect it to operate well in the dark, just enough quality and zoom to capture plates going through the access road during the day, about 14ft/4m wide.
In terms of networking and storage, I'd rather an IP camera obviously, and WiFi would be preferable, but I would also be fine with a non-networked camera with an SD card / external drive for storage.

Thank you for any help finding a relevant product.

 

[wittaj]

330 feet is a tough distance.

You need a camera that can optically zoom to that distance. Digital zoom only works in the movies and TV.

Through a window (if that is what you are saying) would be impossible as the camera would need infrared at night. And it could result in focus issues during the day at that distance.

Wifi - forget about it. Wifi is problematic for surveillance cameras because they are always streaming and passing data. And the data demands go up with motion and then you lose signal. A lost packet and it has to resend. It can bring the whole network down if trying to use it through a wifi router. And then you are far enough away that you would not have full signal, and it will slow your whole system down.

Unlike Netflix and other streaming services that buffer a movie, these cameras do not buffer up part of the video, so drop outs are frequent. You would be amazed how much streaming services buffer - don't believe me, start watching something and unplug your router and watch how much longer you can watch NetFlix before it freezes. Now do the same with a wifi camera and it is fairly instantaneous (within the latency of the stream itself)...

Most consumer grade wifi routers are not designed to pass the constant video stream data of cameras, and since they do not buffer, you get these issues.

This is the goto camera for most of us, but the most anyone has reliably got out of it is about 240 feet:

Amazon.com : Loryta IPC-HFW5241E-Z12E IP Camera 2MP Starlight WDR IR Bullet AI Network Camera English Version

Amazon.com : Loryta IPC-HFW5241E-Z12E IP Camera 2MP Starlight WDR IR Bullet AI Network Camera English Version

www.amazon.com

If you are only concerned about daytime and do not need nighttime plate reading, the PTZ would be about the only way to do it without a really expensive camera:

Amazon.com : Loryta SD49225XA-HNR 2MP 25x Starlight + IR PTZ AI Network Camera Auto Tracking Support PoE+ English Version

Amazon.com : Loryta SD49225XA-HNR 2MP 25x Starlight + IR PTZ AI Network Camera Auto Tracking Support PoE+ English Version

www.amazon.com

Reach out to @EMPIRETECANDY as he is the seller of these referenced cameras.

 

[sparrowcup]

Thanks for the quick reply!
That second link may be a good option.
I should also mention, I have an advanced technical understanding - so if, for example, you know of a camera module for e.g. a Raspberry Pi that has extended optical zoom capabilites, I could also process the video separately and pull license plates using some open source solution. I'm more interested in capturing the video itself than the processing, the camera would be of use only in an event of e.g. a theft, in which case I would even go back to the recording and jot down the license plate manually.
Also - assuming infrared and nighttime recording are unnecessary, would optical zoom through a window be fine?

 

[wittaj]

I don't know if a pi cam would have the optical zoom needed. At that distance you are probably in the 120mm range.

If the camera it flush to the window it may work, but if it is at any angle, then you run the risk of any glare or reflection from inside messing with the focus.

 

[sparrowcup]

I don't know if a pi cam would have the optical zoom needed. At that distance you are probably in the 120mm range.

If the camera it flush to the window it may work, but if it is at any angle, then you run the risk of any glare or reflection from inside messing with the focus.

So something like this wouldn't suffice in terms of zoom? Found from quick Google search:

50mm 8MP Telephoto Lens for Raspberry Pi High Quality Camera with C-Mount

This is a 50mm 8MP Telephoto Lens which is suitable to use with the Raspberry Pi High Quality Camera. It has a high level of zoom and can be used to target specific subjects located far away. It has a fixed focus of F1.4. The lens can be easily screwed into the Raspberry Pi High Quality Camera...

www.seeedstudio.com

 

[wittaj]

Nope not even close.

The Z12E that someone has stretched out to about 240 feet is a 64mm camera, and this one is 14mm smaller, which is a huge difference in these types of cameras.

I guess you could always try it. The USA plates are pretty small compared to other parts of the world where the plate is the size of a bumper LOL. If yours are that large then it might work.

 

[sparrowcup]

That's a shame... what distance would you guess the Raspberry Pi cam I linked could cover? The Z12E is rather expensive for my needs at the moment.

 

[biggen]

50mm may get you to 150'. But even then I doubt it.

At your level of zoom needed you looking at a much more expensive camera. Your best bet would be to get the camera closer to your target.

 

[bigredfish]

^^^^
Yup

 

[wittaj]

And keep in mind that the focal length needed is only part of the equation.

The camera has to also be able to manually set shutter speeds and not play with the image to make it look good as a static image but be a total blur for movement.

We see many people come here wondering why their camera cannot get plates. Optical zoom is part of the equation, but with poor/cheap sensor and firmware, you end up with a blur even if you have the optical zoom part down.

 

[biggen]

^^^

And optics quality. How good is that aftermarket optic compared to the Dahua/Hik/[insert any other well known camera manufacturer]?

Who knows. /shrugs

 

[sparrowcup]

I see, there are multiple considerations here. Thank you for all of the input, I have some thinking to do.

 

[looney2ns]

Study here: LPR | IP Cam Talk
You can use this to help determine what focal length lens you would require.
IPVM Camera Calculator V3

 

[samplenhold]

I have two PTZ cams running from behind windows that are about 90% affective. I do not use the IR on those cams and they are not being used for LPR. However, there are some considerations to address:

• If you put a heavy black fabric behind the cam, that will almost completely eliminate any reflections from inside the window and behind the cam.
• If you use an outside/external IR emitter you will not have the problem of the IR bouncing from behind the window.
• Rain or any moisture on the window will make the image unusable.