Quote Originally Posted by rhino View Post
A few things that I've read that may influence the range your after are the color of the lens... I think a clear lens works better
I tried a couple of type of red lensed LEDs, barely got any results at all. Tried a clear-greenish lensed, got some results, but nothing useful. The LEDs I ended up using were IR LEDs. You can barely see them in that 'video' I made. They show up on the camera, but you can't really see them.

and the amount of ambient light in the room. It would be an easy experiment to see how it reacts in total darkness compared to whatever your normal lighting conditions are
I sorta wrote the code to compensate for ambient lighting. I'd keep track of the high and low values and the one that was the darkest was the one with my finger over it. And the code on the site isn't exactly the finished product. The 'real' code (before I shelved the project) had a couple of extra lines in it to 'reset' the high and low values over time so they wouldn't get 'stuck'.

http://www.edn.com/article/CA6387024.html
That same video is where I got the original idea from.

And of course Skimask has video proof that it works, not to mention nice enough to post some code. Nice video!
(Code posting) - First time for everything I guess

Someday, when I get my basement/LAB rework finished (major water damage, repainting walls in the works), I'll put it back together with a few more LEDs and redo the video. Bought the wife a new camera for Xmas last year (or was it me? I forget )...has a really decent movie mode on it.