external IR for cctv

[tin34543 0]

Hi,

 

I need to set up night vision camera with inbuilt IR LED's on the outside of a house/.

 

The camera needs to be fully hidden so it can not be seen by anyone. I can obvioulsy

hide the camera in many ways which is fine during the day, but at night the RED IR LEDS's

can be seen.

 

So...

 

Is there any way to hide IR LEDS so they cannot be seen? At night they are very visible and

give the location of the hidden camera.

 

Thanks

 

PT

[Soundy 1]

Get a camera with 950nm LEDs. Regular 840nm versions are just on the verge of human sight, spilling slightly into the red... the longer wavelength takes it outside that range, so they're not visible to the naked eye.

 

The catch is, you will probably need a different camera as well, and they're not as cheap as the more common models.

[rory 0]

What Soundy said, you need IR with 930nm+ (eg. 940nm, 950nm etc), and a camera sensitive to that Infrared spectrum. One catch is as you go higher you loose IR distance or have to compensate by raising the power to it, or narrowing the beam in some cases.

[Nimrod 0]

Use this filter over your ir leds.

 

http://www.edmundoptics.com/onlinecatalog/displayproduct.cfm?productid=1918

 

If link does not work search for this.

 

edmund optics Optical Cast Infrared (IR) Longpass Filters

[tin34543 0]

Thanks peopl!

[EarlT 0]

Use this filter over your ir leds.

 

http://www.edmundoptics.com/onlinecatalog/displayproduct.cfm?productid=1918

 

If link does not work search for this.

 

edmund optics Optical Cast Infrared (IR) Longpass Filters

 

I assume those filters diminish the light the camera can see as well. Is it significant?

[Nimrod 0]

“I assume those filters diminish the light the camera can see as well. Is it significant?”

 

From looking at grafs on product page it looks like you louse about 10% of ir light.

[ak357 0]

Use this filter over your ir leds.

 

http://www.edmundoptics.com/onlinecatalog/displayproduct.cfm?productid=1918

 

If link does not work search for this.

 

edmund optics Optical Cast Infrared (IR) Longpass Filters

 

I don't get it

if u have IR Led why would u put this filter over IR Led

filter u recommend is long pass meaning to block visible and pass IR

u see my point and/or ?

plx explain your logic

are u suggesting it will hide his 850nm IR ?

I don't think its gonna happened

[Nimrod 0]

“I don't get it

if u have IR Led why would u put this filter over IR Led

filter u recommend is long pass meaning to block visible and pass IR

u see my point and/or ?

plx explain your logic

are u suggesting it will hide his 850nm IR ?

I don't think its gonna happened”

 

The small amount of light he can see given off by the ir leds is in the visible spectrum. Putting the ir filter over the ir leds will block this light.

[ak357 0]

 

The small amount of light he can see given off by the ir leds is in the visible spectrum. Putting the ir filter over the ir leds will block this light.

 

Been there done that

very minimal effect with actual IR reductions

but always good idea to try

one more way to learn

[Nimrod 0]

“Been there done that very minimal effect with actual IR reductions”

 

Do you have any idea what this thread is about or what i recommended? The original poster has a problem of the dull red glow from the ir leds giving away the its position and intent. He wants to get rid of the faint glow. The faint glow of the ir leds is visible light, this is the light that needs to be filtered out so his led assembly can not be seen. The ir filter i recommended filters out visible light NOT ir light. I do not know why you have such a big problem with the difference between ir and visible light but you clearly have them mixed up. Read this 3 times “The filter lets the ir light thru and blocks the visible light.” And then think about what the original poster is asking for, NO VISIBILE LIGHT FROM THE IR LED ASSEMBLY. Now, do you finally understand this, or do i have to rub your face in it a few more times.

[ak357 0]

“Been there done that very minimal effect with actual IR reductions”

 

Do you have any idea what this thread is about or what i recommended? The original poster has a problem of the dull red glow from the ir leds giving away the its position and intent. He wants to get rid of the faint glow. The faint glow of the ir leds is visible light, this is the light that needs to be filtered out so his led assembly can not be seen. The ir filter i recommended filters out visible light NOT ir light. I do not know why you have such a big problem with the difference between ir and visible light but you clearly have them mixed up. Read this 3 times “The filter lets the ir light thru and blocks the visible light.” And then think about what the original poster is asking for, NO VISIBILE LIGHT FROM THE IR LED ASSEMBLY. Now, do you finally understand this, or do i have to rub your face in it a few more times.

 

 

Hmmm, looks like u miss my point, but that ok ( kinda remain me TVL= pixel talk )

with your attitude and words in your post

I don't think I wanna keep going

we just had another i...t Brandon on forum

but at least he was kinda polite and well spoken

[rory 0]

Use this filter over your ir leds.

 

http://www.edmundoptics.com/onlinecatalog/displayproduct.cfm?productid=1918

 

If link does not work search for this.

 

edmund optics Optical Cast Infrared (IR) Longpass Filters

 

Wont that work both ways though?

Such as the light going into the camera? (if its an IR camera)

Also if the IR is 730nm or higher looks like it wont block that, which is the glow you get from those 730-840nm IR?

Seems as if they are just to block all visible light going into a camera, such as with an IR only camera (eg. separate daytime camera or filter removed during the day).

[Soundy 1]

Let's try to keep things civil, kids... everyone seems a little edgy after the last few days' antics, let's just remember we're all professionals here

[Nimrod 0]

“Wont that work both ways though?

Such as the light going into the camera? (if its an IR camera)

Also if the IR is 730nm or higher looks like it wont block that, which is the glow you get from those 730-840nm IR?

Seems as if they are just to block all visible light going into a camera, such as with an IR only camera (eg. separate daytime camera or filter removed during the day).”

 

Rory i am having a little trouble following you questions, let me try and see if i understood what you are asking.

 

1) You could use this filter over the camera to block visible light and just get ir light, if that is what you were getting at.

 

2) “Also if the IR is 730nm or higher looks like it wont block that, which is the glow you get from those 730-840nm IR?” I see what you are saying here, i looked very carefully at the chart and it looks like 730nm is on the visible side of the cutoff. I have not tried this edmund filter, but i have a dark red ir filter that when placed over ir leds i have to have my eye a 12 inches or closer to the filter in the dark to see anything at all. So it is a tough call if this edmond filter will be better or worse.

 

3)”Seems as if they are just to block all visible light going into a camera, such as with an IR only camera (eg. separate daytime camera or filter removed during the day).” I could not follow this at all.

[rory 0]

3)â€Seems as if they are just to block all visible light going into a camera, such as with an IR only camera (eg. separate daytime camera or filter removed during the day).†I could not follow this at all.

Something like a dual CCD camera where the color camera is for day and the BW is for night, the BW in some cases only needs the IR light such as where its pitch dark at night, although normally they use an IR pass filter which doesnt block all the visible light out. So ... nevermind my bad ..

[Nimrod 0]

OK guys, your getting it late but you are getting it straight. Rory got me thinking about the cutoff for ir filters and i want the same thing the original poster wanted except i want to use mine for an covert license plate camera. So i googled around a bit and much to my surprise ir filters are available from at least 650 to 1000nm in 7 increments. Search for this phrase on ebay and look at his store.

 

Infrared IR Optical Grade Filter for Lens

 

The 650nm are the ones to get if you want to cut out all visible light.

[rory 0]

Although .. they could always just buy the 940nm IR to begin with.

Although its not as easily available for lower priced gear like bullet cameras.

[dvarapala 0]

Something else the OP might want to consider is "Perspex CS Black 962." This is basically black Plexiglas that blocks visible light but allows most of the IR light to pass through. Depending on the cutoff curve, this might also help to filter out the telltale red glow from his 850nm IR LEDs. One could hide both the camera and the illuminators behind a sheet of this stuff and have complete stealth; the downside, of course, is that it's going to cut down on some of the transmitted light, and one would need stronger illuminators to compensate.

[mike_va 0]

OK guys, your getting it late but you are getting it straight. Rory got me thinking about the cutoff for ir filters and i want the same thing the original poster wanted except i want to use mine for an covert license plate camera.

Just for kicks I bought some of that Edmund stuff, a square piece. Came in the mail yesterday.

 

Cuts down greatly on headlight glare but not completely. During the day with the camera in color makes things look funny. Remove the ICR on the camera and it "sees" fine during the day in B&W - would be a good way to do a covert w/o using a pinhole lens.

 

Also, and this was unexpected - blocked most of the visible light from a lamp outside. This would be useful if a particular light was messing up the exposure at night.

 

Look forward to hearing about your license plate experiments.

[rory 0]

Also, and this was unexpected - blocked most of the visible light from a lamp outside.

 

Yeah thats what it says it does basically, blocks visible light which the lamp would be.

During the day there is alot of Infrared from the sun so much of that should pass through.

[Nimrod 0]

mike_va, thank you for buying this filter, could you do an experiment for us. Place this filter over a regular cctv ir led light source, and at night tell us how close you have to get to see the faint red glow of the ir leds.

[Nimrod 0]

“The 650nm are the ones to get if you want to cut out all visible light.”

 

Sorry guys i made a mistake, 650nm is on the wrong side of the cutoff, this would mean 650nm and up would be transmitted making the 730nm ir leds visible. I should have said use the 760nm filter.

 

I did find another place for filters looking at specs now.

 

Chart of there filter cutoffs are here.

 

http://www.maxmax.com/aXNiteTreeFilterComparison.htm

[Numb-nuts 1]

It must be the end of the mating season !

[mike_va 0]

could you do an experiment for us

Yes, but will have to be this weekend.