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license plate camera with 940nm

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Does anyone make a security camera to read license plates (image only) that uses 940nm ir's? I have found a number of cameras that will show plates but they are either 850nm leds or don't give any specs on the wave length. I would like to keep the cost around $300 or less. Distance I need is about 80 feet.

Thanks

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I'm not using any lens, I'm looking at license plate capture cameras and really getting confused with all the different ones out there. It will be mounted 8 feet off the ground and needs to see 80 feet or more.

 

What would be a decent lcp camera for my purpose? I need the 80 feet and would like to keep the price down. I could live with 850nm.

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I'm not using any lens, I'm looking at license plate capture cameras and really getting confused with all the different ones out there. It will be mounted 8 feet off the ground and needs to see 80 feet or more.

 

What would be a decent lcp camera for my purpose? I need the 80 feet and would like to keep the price down. I could live with 850nm.

 

 

Hi. The problem is camera sales people will say it's a APR / LPR camera when infact its not.

 

Take a look at bosh Anpr cameras or geovision but your budget is a bit low

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I'm not using any lens

 

Your camera MUST have a lens on it, is it a fixed or vari-focal lens? If it is fixed, what are the specs? If it is vari-focal what is the the range of focal length? What is the F-stop number?

 

Is your problem with 850 the red glow? At 80 feet no one will even see it.

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I'm not using any lens

 

Your camera MUST have a lens on it, is it a fixed or vari-focal lens? If it is fixed, what are the specs? If it is vari-focal what is the the range of focal length? What is the F-stop number?

 

Is your problem with 850 the red glow? At 80 feet no one will even see it.

 

No offense, but I think you are reading my question wrong. I don't have a lpr camera yet. I'm in the market for one and am getting really confused with all the "specs" on them. My biggest concern, besides price, is that I need 80 feet distance.

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No offense, but I think you are reading my question wrong. I don't have a lpr camera yet. I'm in the market for one and am getting really confused with all the "specs" on them. My biggest concern, besides price, is that I need 80 feet distance.

 

You are going to need to rethink your budget. For what you want to do I would be budgeting around $1000 minimum.

 

At that range you will need a box camera with something like a 12.5mm - 50mm varifocal on it to make sure you have enough pixels per metre to read the plate at that distance. You are also going to need a big IR illuminator. 940nm IR is far less effective then 850nm. Most people report about half the distance vs 850NM.

 

Remember that for clear captures your shutter speed will need to be up to which reduces the amount of light you get in again.

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Goal

To read a license plate at 80 feet including at night, it can be done. So the final result should be able to focus in on an area about 10 feet wide for a vehicle entrance/exit.

 

Lens

At 80 feet, this means about a 38mm-42mm lens on the camera for a 10 foot wide view. Going to a 20 foot wide view means about an 18mm-20m lens.

But those higher zoom lens cost monayyy!

 

Two sites to play with (I'm not affiliated with either one):

Simple field of view calculator:

https://www.pelco.com/partners/tools-calculators/camera-lens-field-of-view-calculator-fov

 

Another calculator, but with a "simulator." This one has a "Vehicle Entrance" example...choose that, then change the "Viewable Dimensions" setting down below to 10, 20, or 30 feet to get a general idea of the field of view (but not necessarily the resolution).

http://polarisusa.com/pvi4

 

So a camera such as the Hikvision's DS-2CD2T42WD with a 12mm lens, it's within the price range, but even getting a 12mm lens on it, you're looking at a view that is about 30 feet wide...that's like 3-4 cars lined up next to each other...good enough for reading a license plate? Maybe at 4MP...maybe...in the daytime.

 

As mentioned above, a varifocal camera that has 12-50mm lens would let you choose the exact field of view you wanted.

 

Resolution/high-def

Most of the cameras for everyday use are typically 2.8mm-4.0mm. Going to a higher resultion camera such as 3 or 4 megapixel will help quite a bit...but not enough for an 80foot shot of reading the plate number.

 

Night time

Not making this easy on the cam, are we...hehe.

IR does work, but range is limited. And even then, we simply don't get as good of detail when compared to daytime. Such is the technology in 2015. But we only need it to read the plate numbers. Many times the camera will say it has an IR range of 100 or 160 feet. Typically in real-world use, I find about half their claimed distance is more usable.

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Goal

To read a license plate at 80 feet including at night, it can be done. So the final result should be able to focus in on an area about 10 feet wide for a vehicle entrance/exit.

 

Lens

At 80 feet, this means about a 38mm-42mm lens on the camera for a 10 foot wide view. Going to a 20 foot wide view means about an 18mm-20m lens.

But those higher zoom lens cost monayyy!

 

Two sites to play with (I'm not affiliated with either one):

Simple field of view calculator:

https://www.pelco.com/partners/tools-calculators/camera-lens-field-of-view-calculator-fov

 

Another calculator, but with a "simulator." This one has a "Vehicle Entrance" example...choose that, then change the "Viewable Dimensions" setting down below to 10, 20, or 30 feet to get a general idea of the field of view (but not necessarily the resolution).

http://polarisusa.com/pvi4

 

So a camera such as the Hikvision's DS-2CD2T42WD with a 12mm lens, it's within the price range, but even getting a 12mm lens on it, you're looking at a view that is about 30 feet wide...that's like 3-4 cars lined up next to each other...good enough for reading a license plate? Maybe at 4MP...maybe...in the daytime.

 

As mentioned above, a varifocal camera that has 12-50mm lens would let you choose the exact field of view you wanted.

 

Resolution/high-def

Most of the cameras for everyday use are typically 2.8mm-4.0mm. Going to a higher resultion camera such as 3 or 4 megapixel will help quite a bit...but not enough for an 80foot shot of reading the plate number.

 

Night time

Not making this easy on the cam, are we...hehe.

IR does work, but range is limited. And even then, we simply don't get as good of detail when compared to daytime. Such is the technology in 2015. But we only need it to read the plate numbers. Many times the camera will say it has an IR range of 100 or 160 feet. Typically in real-world use, I find about half their claimed distance is more usable.

 

Thanks for the info, this helps me a lot.

I can deal with the 850nm ir"s instead of the 940's.

I found this camera on ebay. Is this something that would work? http://www.ebay.com/itm/LPR-License-Plate-Camera-Professional-Recognition-1-3-Sony-CCD-6-60mm-Zoom-Lens/181455649502?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D33097%26meid%3De8b688af3bb3448b96579d43a37e25af%26pid%3D100005%26rk%3D4%26rkt%3D6%26sd%3D190843835824

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That camera is analogue and I would not trust the inbuilt LEDs to illuminate the plate at any distance. Your field of view with that cam is only going to be circa 2 metres (7') or so at enough pixels per metre to read a plate.

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I have given up on the 940nm ir's and will stay with 850nm. I also have to stay with analog. My QSee dvr (qt5516 & QT5716) doesn't support IP. I found this camera (http://www.cop-usa.com/ebproductdetail.asp?id=740) I like the remote feature since it's going to be about 8 ft on a pole. OSD from the dvr would be better. Any comments?

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I really only use two companies for IP lights. Raytec and Axton. I tent to repfer Axton for two reasons. First they are built in the USA and second, they are more affordable than Raytec usually.

 

Both of these companies make top notch illumination to suit your needs. You may also want to look at mounting white light closer to the target area, it would just help to counter balance the lights on rear of the vehicle and assist your camera in seeing clearly.

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I really only use two companies for IP lights. Raytec and Axton. I tent to repfer Axton for two reasons. First they are built in the USA and second, they are more affordable than Raytec usually.

 

Both of these companies make top notch illumination to suit your needs. You may also want to look at mounting white light closer to the target area, it would just help to counter balance the lights on rear of the vehicle and assist your camera in seeing clearly.

 

They are great illuminators, as are Bosch, but they are more expensive than a cocaine habit. The illuminator I have on my numberplate cam does the job nicely and cost $44.

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