“I used 8 of these to cobble together an illuminator ring for a Naturebytes camera case. Using the NoIR version of the Pi camera they provide a good beam of light and being 940nm IR they are completely invisible to human and animal eyes (I hear 840nm LEDs used in security cameras have a dim but visible red glow). I connected them 2 in series with a 20ohm resistor which draws 90 to 100mA from a 5V supply.”
