Infrared For Sure

Learnt something new today. It turns out that LED lights emit some infrared light, though not a massive amount (see yesterday's blip for some sunny infrared pics). Goes to show that one should be aware of imitations as I experienced at the end of March. I simple test of holding the R72 filter up to a light source (the sun or a tungsten light bulb would be better) will show whether or not any light would pass. An 850IR filter would be almost completely black to the naked eye.

See here for the fake infrared Urth filter.

Enjoy.