A few basic questions about IR lights


Young grasshopper
Jan 23, 2016
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A few years ago when I bought some 4k Dahua cameras direct from China I also bought some IR lights. The housings were half-spherical, about 2 or 3 inches in diameter, some had a face full of small regular-sized LED's, others had 4 high-power led's with lens in front of them. Both types of lights had a thin flat glass front cover that you could unscrew. The 4-LED high power units failed fairly quickly - each one had failed on the LED in the same position. Must have been a board defect. I removed the bad LED and bypassed it with a regular diode and got them working as 3-LED units and they've been working fine. They put out a lot of IR light. The units with dozens of smaller regular-sized LED's don't put out a lot of light, maybe they're good for up close (like a front porch or front-door camera) but not for a front yard or small parking lot.

I'm seeing other IR lights where they have a single large (maybe 1" square?) LED element sitting at the bottom of a square aluminum reflector, housed in usually a black-framed fixture about 6" x 6" with large glass front plate and large heatsink for the back of the fixture. These have labels on the front that indicate their wattage (from maybe 4 to 10, even 20 or more watts) and also say "IP-66". It's those type (single high-power LED) that I don't have any familiarity with - was wondering if they'd be good as a long distance, wide (and even) coverage for a small parking lot if mounted high under the eves of a 2-story building. Desired Illumination distance about 100 feet.

Also what wavelength should I be looking for? I'm seeing 850, 940 and 740. What is best for these IP cameras - or does this vary by make?


Known around here
Jun 30, 2018
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The vast majority of cameras can see 850nm...it can depend on who made it.