From Gampa Geek via Nikon Hacker:
There are quite a few motion sensor hacks out there, but I wanted to do one for my new Nikon D5100 that was non-invasive and was completely detached from the camera. The D5100 is a high quality camera and takes great photos > 16MP and video in 1020p HD. This hack should work for any compatible IR and camera. Just hack the IR for your camera. There are cheap IR RC copies out there.
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