Activating Camera Shutter via CHDK

Mark VandeWettering over at Brainwagon gave me a CHDK clue... it's been sitting in my mailbox for a while, so let me get it up here:


It's been a while since I looked at this, but I don't think it's difficult at all. If you look at the "home made usb remote" cable: 

http://chdk.wikia.com/wiki/USB_Remote_Cable 

Basically, if chdk has the usb remote trigger support in it, it monitors V+ on the usb input port, and when it goes high, it triggers the shutter. So, just attach it directly to the arduino GND and any digital pin, and you should be able to trigger the shutter.

And related, Arduino Control for EOS Cameras.