# Looking for Modder to swap IR LED in Pentagonlight Weapon Light



## eg1977 (Sep 9, 2012)

I think the IR LED is not working. Do you think it's possible to install a red Cree XPE? About how much would that cost?


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## bstrickler (Sep 11, 2012)

What makes you believe it's not working? IIRC, these are running at 940nM, rather than the typical 850nM that most IR LED's run, which means most cameras won't see the LED when it's on (other than maybe the night time B&W security cameras).

When replacing it with a red LED, you'd have to change the focal point, because IR has a totally different focal length than visible light.

Here's an example of what I'm talking about (in photography terms)

http://dpanswers.com/images/irfm2.jpg
The red marks indicate the focus point required for IR.


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