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stabmaster

Questions, infrared questions et. al

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Hi again. I am revamping my CCTV setup and I could use some help, as you folks had so graciously done in the past.

 

Short version: Members of this forum helped me out months ago to get my security system done in my RV park. I ran a pole in the ground, a serious 130W solar panel, a pair of 12v batteries, and I'm running 24V on 2 outdoor cameras.

 

Now my question is about converting these to infrared. I don't know if it's much of a good idea at all. Mainly, the idea is to be able to pick up license plates and vehicle makes/models at night time.

 

The trick is that the headlights and taillights are going to close the iris and all I end up with is two bright dots on my screen.

 

In a perfect world, i would have a good normal day camera (B/W or color, not important), and at night the infrared lights would show up and the camera would cut off all non-ir frequencies. Not only that, but somehow it would be sensitive to only one certain IR frequency. If i could choose i would pick 880nm-- because this is the frequency which appears to have the highest candela per watt (efficiency) according to one reference.

 

Since I'm running 24v off of my solar panels right now, I would hope to find all of this in 24v application. Oh yeah, I would also like this to be done on the cheap.

 

So the first problem i am facing is finding a varifocal auto iris 24v lens with IR lights integrated. Something like the following is what i would hope to find:

http://www.supercircuits.com/index.asp?PageAction=VIEWPROD&ProdID=3575

but in varifocal auto iris 24v form. plus more IR lights would be nice

 

Unfortunately i doubt this is going to happen. I could go with one of these:

http://www.ledtronics.com/ds/PAR20/default.asp

its a PAR20 IR with the angle of my choice. Since i think they're normally used for track lighting, i would probably find a hard time locating an outdoor housing. Luckily i have some Pelco camera housings that i'm not using that could work (and it wouuld be more intimidating with 4 camera housings!).

 

But i digress. I would like to solve this mystery. Is this just much ado about nothing? Am I sunk here?

 

A little help is much appreciated.

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Unless you get some high powered IR Spots you wont get any distance, so doing it cheap, basically wont work ..at least not from the poles you have the existing cameras on.

 

Theoretically, you could use a 5-50mm lens, zoom it in on the lane width, use a good camera with back lighting, or wide dynamic, and then put IR LEDs closer to the lane, just to illuminate the licence plate area. If you have alot of light also, it will work. Also, slow shutter speed on the camera if it allows that. But the camera can only be used for licence plate, nothing else.

 

there is another thread here on IR may be of help also.

 

rory

 

PS..welcome back...

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thanks rory. I am actually putting more cameras up inside the laundry room and elsewhere indoors, so i was hoping to find some more effective cameras to throw on the poles, and then scavenge the existing cameras for indoor use.

 

i doni't NEED to get license plates, but i would like to be able to resolve the types of vehicles at least, to identify who is in them (i live in a small enough town where this would be possible). I think that the locals have slowly gotten bolder at night time, knowing that we are basically blind at night. Also, some people only come through at night and don't even know we have cameras.

 

Anything that would increase our night vision would be helpful. I havve the ability to run IR from a remote location onto the vehicles... which i will probably do. Any suggestions on the camera? The big black hole in my head here is thus: the average B/W night camera probably won't perform as well as the camera made for IR, correct? What specification reflects a cameras ability to resolve IR light? thanks!

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Sanyo has a good Day Night I used with IR, so thats proven for sure.

 

Ill try to find a link and post it here.

 

Or GE does also have a Day Night for IR, up to 1100nm. KTC-2000DN, little bit more expensive.

 

I didnt use a special day night or IR compatable lens on the Sanyo one i did, but now adays you can buy them so may as well.

 

Basically if you want invisible you will need to check the Spectral Response of the camera you are choosing. The 2 listed above go up to tne invisible IR range. If you dont know, then 730nm would be the IR to choose. If it is a good BW camera, generally at least it should support 840nm.

 

I used the OEM spots and though they claimed 150' they never got close. So I switched to Extreme CCTV IR and it worked - not cheap though, but you get the distance.

 

It could be cheaper to use some normal artificial lighting though, at least initial costs, and use an Exview Color Camera.

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quote: "What specification reflects a cameras ability to resolve IR light? thanks!"

 

Lux rating. You'll want a low lux rating, with low light cameras this is usually expressed as "0.3" ; "0.002" ; etc. The lower the number, the more sensitive the camera is supposed to be to light in the IR spectrum.

 

Now, the lux rating could be what the chip is capable of, but your actual end product might not be exactly the same due to differences in cameras, lens, etc. However, the lux rating is your general guide.

 

Note also that not all chips are the same. For low light, I'd recomend a black and white 1/3" Sony SuperHAD, or ExView. The Sony chips are (IMNSHO) offering the best low light performance currently. Something about how they are made allows them to work better with IR spectrum light. I don't know how the magic works, but it does. The black and white cams will provide better resolution, which will be important for tag and facial ID.

 

If you want invisible active IR illumination of the target area, you are going to want to get IR LEDs that peak equal to or greater than 940nm. Anything lower and you will get a tell-tale glow at the light source.

 

Headlight wash could be a problem, depending on other lighting conditions present.

 

I might suggest, for vehicle ingress cameras, that you channelize in some way to slow traffic down. You maight install a speed bump, gate w/access control, a curved entrance lane making them slow and turn, etc. - you get the idea. This slows the vehicles down making it easier to get a better shot over more frames.

 

With or without doing the above, I might also recomend some visible security lighting. This helps prevent problems and is a good basic safety and security measure. It will also help you get good quality images.

 

A cam that is well designed to work in this application at night may not work very well at all during bright outdoor daylight conditions. If you want one came to handle both, then a day/night cam will be worth looking into. However, and this just my personal opinion, but I'd rather use two cameras... one for bright lighting (day) and one for dark conditions (night). This will assure me good images either way.

 

Hope this helps!

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INEX has a very interesting solution. License plate reading technology that actually works with US license plates. Reads the license plate on a moving vehicle (up to 80Mph) in less than 200ms.

 

http://www.inextek.com

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License Plate recognition is incredibly difficult at night. The only way that we have found it to be successful is first the vehicle must almost be still. If moving at a fast pace we have had cameras with cut filtering and the use of IR's that will pick up the plates but not always. Extreme is supposed to be coming out with some new cameras to handle this situation. They say they are showing it at ISC next month. We will see.

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The trick is that the headlights and taillights are going to close the iris and all I end up with is two bright dots on my screen.

 

your going to want a camera that can handle vertical smearing, when a car headlight flares the picture and makes it overshoot, some cameras, not very many can eliminate the vertical smearing, thats why when headlights are on recordings you get that white line up and down the picture.

The Bosch XF is the best in the market for this!

 

I might suggest, for vehicle ingress cameras, that you channelize in some way to slow traffic down. You might install a speed bump, gate w/access control, a curved entrance lane making them slow and turn, etc. - you get the idea. This slows the vehicles down making it easier to get a better shot over more frames.

 

or use a camera with faster shutter speeds, again the XF has a traffic mode, made for this purpose and the good thing is it has three modes, so you could havea day mode, then trigger from a relay for traffic at night time or low light being the third mode.

 

your also going to want a IR corrected lens so that you get the best results and choose a camera that not only has a removable cut filter but has one that replaces it so you still get the correct wavelight pattern, many simply remove the filter, all colour cameras have a filter for IR lighting and some daynight cameras can remove this filter, the nex XF daynight cam is the best I have seen at this and the SD from Panasonic.

 

Remember that zooming in will limit the amount of light getting to the sensor I would go for a Manual Iris lens if you dont want to muck about and a motorised Iris if you really want to...

 

The best solution for you would be the new XF Daynight as you could program it up the coax for 2 modes, then ytou can adjust levels and iris settings for different time spans, for example a faster shutter in the daytime when you do not need as much light.

 

Make sure to use IR Corrected lenses though.

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thanks for your help everyone. I have been looking into everything that has been suggested.

 

I'm removing the really super-cool solar panel setup that i built and i'm going to try to hardwire 110v and hardwire the video. I think the distance is 150' - 200' but may be less.

 

Is there going to be huge line loss issues with this? I assume that the voltage drop accross the coax (rca) line will be too great.. but i don't know.

 

I did read that I could go with an IP converter which will give the ability to run fiberoptics over the long stretch. the advantage here is that i will have no interference at all. I will also have the ability in the future to screw around with PTZ or some other whackyness (i guess?!).

 

Anyways am i on the wrong track?! there is so much to consider!

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3 ways; RG-59 or RG-6 cable with power (siamese), UTP (CAT5) with a balun, or fiber. Fiber is the most expensive. RG the least. UTP is the middle of the road. RG is easier to cable, connect, and repair and the problems will be less. UTP is harder to "put together" as your balun and cable are very prone to inter and ground loop issues (time to buy a choke). Fiber is great but the install and cost will be a new road to plan, connect, and repair. I would install a underground 2" PVC pipe, over and 1 ft. or more above the ac power line (most codes call for a underground to be 30" or more). and then run siamese RG. Rent a power trencher as it is worth the money spent.

 

I've done the pipe, ac, utp, and balun's. RG is the more reliable on 250ft or less runs. anything longer will force you into UTP or fiber.

 

If you are going with a PTZ later you need to make sure you run that cable also. I'd recommend doing that with UTP.

 

And buy decent cable, baluns, connectors, and ect. it won't hurt you to also run extra cable in the pipe and also to run a heavier underground cable, just in case you need more camera/power down the road.....so to speak.

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Sorry it's been so long.. I'm always out of town doing one thing or another.

 

The information is very useful. I don't understand, though, what a siamese powered RG6 does-- more specifically, is the RG6 actually powered (amplified) by this pos/neg connection or is this pos/neg used to power the camera?

 

if the latter, why would one run a power line seperate from the signal line when they are already run together?

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Sorry it's been so long.. I'm always out of town doing one thing or another.

 

The information is very useful. I don't understand, though, what a siamese powered RG6 does-- more specifically, is the RG6 actually powered (amplified) by this pos/neg connection or is this pos/neg used to power the camera?

 

if the latter, why would one run a power line seperate from the signal line when they are already run together?

 

He just means RG59 Siamese cable, which is RG59 coax with 18AWG Power Cable all in one.

 

There is video loss with any cable that is not amplified. 150-200' best just use RG59 Siamese. Or you could use Baluns with Cat5 then if it isnt any good, you can always add some Cat5 Amplifiers. Personally I stay away from baluns, and just use RG59 or Amplified Cat5.

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