Counter Measures - Security Cam

[KT 0]

Someone is shining somekind of laser light at my ir security camera to darken the picture to almost black. Also, they have a system that blows smoke in front of another ir camera resulting in a white picture on the monitor. Are there any filters or some other counter measure that can be used to overcome this?

 

KT

[Scruit 0]

Can't you identify the source of the light instead? If the light is coming for an area of the screen that is not needed for you direct purpose (ie window of a nearby building then maybe you could shield the light from that area. Can you post a screenshot?

 

Dunno what you can do about smoke other than to ID the source and get it to stop.

[zmxtech 0]

Are they trying to steal a large diamond ?

Call IMF and tell them to bugger off.

 

>might be James bond tho....?

 

jokes aside,

 

not much on that cam as a laser pointer is broad spectrum and goes into the IR region so a cut filter wont help [unless you use just a green filter] that will work and kill off red/IR

 

What you need is a second camera [hidden if possible] And one at the choke points to get face shots before they even get to the area

 

 

 

my 2c

[mcs 0]

Hide a cam looking at the other cam or two, you will find out who is doing it and maybe counter act it...

[atropine 0]

 

not much on that cam as a laser pointer is broad spectrum and goes into the IR region so a cut filter wont help [unless you use just a green filter] that will work and kill off red/IR

 

my 2c

 

Can anyone comment on the effectiveness of Green lasers in destroying a CCTV CCD in night mode (infra red filter removed) or just disabling it?

When lasers are discussed as a security issue by the media, interfering with CCTV's is often one of the 'laser pointers are evil' reasons given for why their availability should be restricted. But I don't know that this is actually even true.

 

My current camera doesn't have any problem with headlights or other small points of lights overriding the exposure, I'd like to think green lasers wouldn't cause it a problem either. I have a green laser, but as I only just bought my dome camera I don't want to shine lasers at it, without knowing for certain that it cant' be harm'd by them.

[zmxtech 0]

YES the red and green high power LASERs can kill each pixel no problems

anything over ~30mW will do it with ease.

 

Also it depends on the beamwidth vs distance vs power.

If they are across the street it will just blind the camera. If they are close pixels will burn. [and go black in color]

 

If its a day night camera with the IR cut filter in 'off mode' at night its worse of course.

 

The cheap green LASERs are a frequency doubled IR LASER and many of them dont have the IR filter so you get 2 frequency spikes green and tons of IR.

 

On top of all that -some LASERs modulate the power so it will cause

funky patterns in CCTV

 

 

At the moment here in Australia idiots are pointing them at aircraft so now they are banning them.

 

 

z

[atropine 0]

That is interesting. ok I won't guinea pig with my new (2nd hand) ptz dome. i might see what damage I can do to an old black and white CCD 1/3 inch camera , though it does have a infra red filter, and I can't see how I can easily remove it to replicate a day/night camera in night mode.

 

 

YES the red and green high power LASERs can kill each

The cheap green LASERs are a frequency doubled IR LASER and many of them dont have the IR filter so you get 2 frequency spikes green and tons of IR.

/quote]

 

You seem to know a fair bit about lasers, My green laser is a dirt cheap one probably without infrared filter. Would the infra red light be focused along with the green light thereby making it extremely dangerous to eyes or would the focussing of the green light by the optics thereby mean the infra red wouln't be focussed as sharply due to it's different wave length?

[zmxtech 0]

yes the cheap green ones are dangerous to your eyes.

If you have an old IR filter you can check your lasers IR.

 

simple test>

1/ test the lasers brightness with no filter -will be bright

2/ laser with filter still bright ? -no internal filter

you can use a light meter also.

 

I would think the LASERS focus would be slightly different 500nm to 1000nm

 

100mW LASERS pop balloons burn skin and lights matches. see wicked LASER site for example.

 

 

z