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ronhithcox

"Halo" image in night time pictures (dome IR)

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using "CNB" dome IR cameras. getting what I believe is RI reflection from inside of dome which obscures image. have made some adjustments and had about a 25% improvement (2 out of 8 camers) but halo still appears in other 6 cams. What would eliminate this reflection but not the "throw" or effective distance of the IR's intinsity at night? (And no, I didn't remove the foam protector around the lense)

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This can be seen in a lot of cameras where the IR does not throw as far as needed for the distance of the viewing area.

 

http://scorpiontheater.com/irlab.aspx

 

Measure from the camera out to the viewing area, and then double this distance, and that is the IR distance rating that you need from your camera.

 

What are your camera's IR distance, and how far is the area from the camera?

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common problem with IR domes. [thats why I never use them]

there is a way of fixing it besides getting better cams.

disconnect the IR inside the camera and run separate IR illuminators you will be surprised on how good the picture will be.

 

my 2c

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thanks guys for your response, the distance is not a problem, I have 2 with much greater distances that have great night images. I am thinking that the "shielding" between the I.R led's and the lens is not adjusted properly.(needs to touch the inside of the dome to eliminate reflection) as far as illuminaters go, I'll have to check into that. makes sense ! thanks again.

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well, "CNB" recalled the cameras, they sent out new cams to replace the old ones (upgraded cams) at no cost, sucked that had to eat the labor tho.

In any case, CNB said that was a bad batch (V176NIR line) amd new cams are perfect. Thanks for the help.

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common problem with IR domes. [thats why I never use them]

there is a way of fixing it besides getting better cams.

disconnect the IR inside the camera and run separate IR illuminators you will be surprised on how good the picture will be.

 

my 2c

 

how is it possible to NEVER us IR? do you mean just domes or IR in general?

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common problem with IR domes. [thats why I never use them]

there is a way of fixing it besides getting better cams.

disconnect the IR inside the camera and run separate IR illuminators you will be surprised on how good the picture will be.

 

my 2c

 

how is it possible to NEVER us IR? do you mean just domes or IR in general?

 

I don't recommend using IR unless you have a good reason for doing so. In almost all ways, the visual results are inferior compared to simply adding more visible light to the scene.

 

As for camera-integrated IR, it's never as good as they say, covers about half the advertised distance, draws attention to your cameras, attracts bugs, and the polycarbonate domes really cut down on the effective distance of IR domes.

 

You're virtually always better off going with separate illuminators. I did so in my current application and have been MUCH happier.

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Also there should be a small grommet or spacer of some sort around the lens to block the IR's from the lens viewing them. That would be your best bet other than putting the IR's on the outside of the dome or disabling them all together.

 

Goodluck,

J

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ZMX hit it dead on the camera is not designed properly a good IR camera will have something separate the IR and the lens so this problem does not occur.

 

 

Also it could be the the IR LED is to big for the dome and when you installed or adjusted the camera you adjusted the IR so that some of them are reflecting back into the dome.

 

This usually happens when you install a camera on a wall without using a proper wall mount.

 

 

But it is most likely not a well designed IR camera.

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first of all, IR Dome design is very important. expensive one is better.

I think there would be lights where the camera is istalled.

If the white ring is happened by IR, the white ring would be looked like the ring with a lot of small rounds.

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I have almost the same problem here. Please see the first (left) and third camera (right). The second camera (centre) is okay.

By the way, I'm using bullet ir camera here. What caused these halo images? Please help...

08122009434.jpg.00935fc29dae637f09ef2a32145981df.jpg

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Put a piece of foam around the ring of the camera and make sure it touches the dome...something to isolate the camera and keep the IR from bouncing back into lens.

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