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Gesualdo

Testing ir

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I have 2 ex40mnx dome cameras with the 940nm ir and on one I am not sure the Ir is working. Is there any way to test it in place? Both cameras by day look great. I am using siamese wire with 18 guage wire and copper shielding and the longest run is 40 ft of cable with the way it is run. I can barely make out the car at 30 ft., the plants and steps which are 6 ft in front of the camera are barely visible. One camera is pretty decent but the otheris crap. The ir for the 2 cameras overlap so there should be plenty of light.

 

The picture also has a lot of snow in it. I am using a Speco T4ip dvr set at superfine 740x480, 15 frames per camera or does this just have crappy night playback? Do I have the contrast too high or do I need more IR. Trying not to have the front look like a christmas tree with packages all over. Would the speco ir200 work with it's 850nm ir for the 940nm filters?

 

I can send someone pictures to view and post on monday if someone will host them.

 

Thanks

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Send me some shots. Also, test it on a TV or CCTV Monitor, not the DVR.

 

If you place something within a couple feet of it you should see the IR beam. Now whether it is putting out the required IR is another thing. Does it have a level for the IR on the camera settings?

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Not sure what you mean by does it have a level for the IR on the cam setting? I don't believe so. I think there was a photocell sensor adjust and thats it. I don't have the directions in front of me, will know more tomorrow when I can get my hands on them and the camera. Will send you a pic tomorrow also.

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I don't know your camera at all but, maybe this is something you could look for. I have a camera that has dip switch's for lux level. Meaning, you can set the camera to switch at 5 lux, 3 lux, 2 lux and 1/2 lux. If all the dip switch's are set to off, the camera will not switch to B/W or night mode.

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I'm sure your IR is working, although I doubt that the camera will see anything.

 

940 nm is considered covert (no red glow). If your camera is not sensitive in this range, you may have to choose a 770 nm fixture (near infrared)

 

Post some pictures so we can see.

 

Rapid

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This is the camera. it is definitely rated for this wavelength. I think I need to find the IR adjustment.

 

http://www.extremecctv.com/products/index.cfm

 

http://www.extremecctv.com/products/uploads/PDF2/EX40MN-EX40MNX_TS_060101.pdf

 

with this camera in it:

 

http://www.cctvforum.com/viewtopic.php?p=34292&highlight=mx4&sid=cba566b6b76f1db8d5edf1b1e548ecfa#34292

Edited by Guest

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OK the only adjustments related to the LED Array is the Photocell brightness adjustment. Will this increase the level the IR is putting out or does it effect the point at which it switches from color to B&W

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you want to look for the IR power adjustment, that is what controls the amount of IR that is put out.

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This adjustment is the only adjustment on the LED Power Board. must be it. the only adjustment posible that I can see. blue screw. I should increase the level to positive side correct?

Edited by Guest

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that has to be it then .. unless there is a switch over adjustment from color to BW but that would be on the camera board .. can you scan the manual and email me it? Or give that a try .. the camera is mounted I take it or you could test it inside a room ..

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OK the only adjustments related to the LED Array is the Photocell brightness adjustment. Will this increase the level the IR is putting out or does it effect the point at which it switches from color to B&W

 

The "blue screw" is photocell sensitive adjustment not "photocell brightness" if you have camera on your hand your may cover the photocell on the IR ring by electric tape and make sure if the motor is switch from the left side to right side(face to camera) if did switch that means camera it will see in the night..

 

if you wants test if 940nm ir workining or not the you may aim another ir sensitive camera to the camera you want to test then you will see the ir through the monitor,if you has only one camera you may cover the photocell by electric tape then put car license plate on the front of camera if the ir on you will see the different though the montitor

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I have picture at night, the camera does switch to B&W and as headlights pass by I have passable picture, I even have the reflectors in the taillights of the truck but I'm not sure if hat is the zir or the result from the streetlight nerby. I believe it is working just not very strong. I don't think the IR is putting out as much as they should be. I sent Rory a couple of pictures if he wants to post them it's OK with me. I tried sending a clip but it takes to long on dial-up.

 

Gesualdo

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I have picture at night, the camera does switch to B&W and as headlights pass by I have passable picture, I even have the reflectors in the taillights of the truck but I'm not sure if hat is the zir or the result from the streetlight nerby. I believe it is working just not very strong. I don't think the IR is putting out as much as they should be. I sent Rory a couple of pictures if he wants to post them it's OK with me. I tried sending a clip but it takes to long on dial-up.

 

Gesualdo

 

if camera switch to b/w that means ir will turns on because they both trigger by photocell which is on the ir ring, and the 940nm ir the best performance distance will approx around 25 to 30 feet, so if no object at front of camera the camera will barely see something only because

even the same material of object will response different reflecting by 850nm and 940nm ir

I will prefer to see the picture ..

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Here are the SnapShots from this Camera:

 

front.jpg

 

truck.jpg

 

So the major object is "tree" and tree is not that good response the ir especially 940nm, from the first of picture you can see ir reflect on some of colsely bush so I believe the ir is on. second picture seems no any good reflecting object on the front of camera the only thing I can see is small bush on the front of camera... so I will say you should use 850nm will be better for this application especially outdoor installation.

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What you are failing to see in the second picture is a chevy s10 pickup truck at most 30 ft away.

If you are correct, then adding more IR will not help the situation then... and Switching to 850nm IR will help. If I understand correctly what someone else has posted earlier, the higher filteron the camera will not detect this lower range even if I were to add it.

I chose the higher nm rating because I did not want the LED showing where the cameras were aimed and chose internal IR to minimize the footprint on the front of the house. I also understood the reduction in output using the higher nm rated filter and figured I would be within limits for this situation but I seem to have missunderstood and did not expect the level of reduction to be as great as it is.

Now my question is; would adding yet another IR element to the front of the house, say an ex12LEDW rated at 940nm and 60 degree wide dispersment work or should I go with a longer range ex26 or UF100? or am I wasting my time and money and should eat my losses and start all over?

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Gesualdo,

 

I've no experience of using your camera, but according to the spec sheet, the manufacturer rates it as a being able to produce images at approx. 40 feet using 850nM LED's.

 

Now, given that the imagers spectral response may be perhaps 30 - 40% efficient at 850nM, the likelyhood is that it's efficiency would drop to perhaps 15 - 20% at 950nM (that's a guesstimated figure!), in which case it may only illuminate at perhaps 8 - 10' from the camera.

 

If that were the case, then you could still use the higher IR frequency, but you are going to need to increase the light level substantially, just to get a reasonable quality image. It may not be an issue with the relative amount of IR being emitted using either 850 or 950 LED's, but simply an imager sensitivity problem.

 

Personally, I'd first want to establish that the camera is working correctly at night, and the easiest way to do that (if you can) is to simply set up a very low level visible light source, perhaps a standard 25 watt or 40watt tungsten bulb in an inspection fitting about 30' from your target area.

 

If you get a good image, then you know the camera is working o.k; if you don't, there may well be a fundamental problem with either the exposure mechanism (auto iris / electronic iris etc.), or the switchable IR filter.

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Hi, Like Coop said, first make sure the cameras are producing a BW image in low lighting . at night ..

 

Send me the day time snap shots again so I can see what is in the way, that will determine whether you use EX26 LEDs or UF100's .. forget the EX12 ... thats only for indoors really .. remember when they spec IR they are really specing that distance inside with alot of close up relecting surfaces, on some of these IRs // when the EX82 sais 150' .. thats indoors . .. they will tell you it is 75' outdoors and still that depends .. so things can differ alot with IR ..

 

Rory

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OK then I need a whole crap more IR to flood the area. They are adjoining areas and I would like to use 1 source to light it. The walklights and walkway are new that are covered in the second night picture.The ones I just sent Rory don't show it. I was thinking 80% efficiency not 20%. MY fault. I believed advertising.

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ok, yeah you normally loose some 20-30% from 840 down to 940 .. also you loose more depending on the width of the IR though that doesnt effect this camera .. just IRs .. but figure that 40' is an indoor rating so expect maybe 30' outdoors with alot of reflection like bushes or a wall, at 840 .. then drop it down to maybe 10-20' with your location and 940 nm ..

 

Camera%20Night.jpg

 

Rain%20Day.jpg

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