external IR for cctv

[Nimrod 0]

It looks like my original idea of using a ir pass filter to get rid of the dull red glow from the 730nm leds is a poor idea. I looked up the transmitted light of a typical 730 nm led and it has a rather narrow transmissive spectrum. Any filter that would get rid of the red glow would also stop most of the ir light from the leds. It looks like Soundy and Rory in the beginning of this thread had it nailed at the start, use higher nm leds.

[ak357 0]

It looks like my original idea of using a ir pass filter to get rid of the dull red glow from the 730nm leds is a poor idea. I looked up the transmitted light of a typical 730 nm led and it has a rather narrow transmissive spectrum. Any filter that would get rid of the red glow would also stop most of the ir light from the leds. It looks like Soundy and Rory in the beginning of this thread had it nailed at the start, use higher nm leds.

 

At least u come to some senses

good

That what I was telling you in my post

I guess I did not worded clear

my fault

[RHP International 0]

There are different wavelengths of IR light. Some are more covert than others. Most likely you're using an IR LED that has a very short wavelength (880nm) that is close to visible red on the EM Spectrum. The only way you can avoid his problem is to turn off those IR LED’s and use an external IR Illuminator in the 940nm range which is completely out of the visible range.

[Aban-CCTV-Camera 0]

If I were you I’d pop into a CCTV shop for a demo of different products,

to actually see how they perform

[mike_va 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.

This made no difference when tested on a bullet IR camera, same amount of glow.

[Nimrod 0]

Thanks for testing Mike.

[Numb-nuts 1]

I pledge $1000...