I thought I had it done! Read the Owner's Manual (Something a real guy never does). Bought a simple single pole, single throw switch. Did everything right. Even tested it on the Canon Powershot Pro1 before I soldered all of the connections. The camera clicked when I threw the switch so I thought we were 'good to go'. Wright? Duffice?... My Canon is apparently one of the few that does not accept the USB, enhanced CHDK software - see http://chdk.wikia.com/wiki/CHDK_for_Dummies". A foot operated shutter release would allow me to stay in the painting zone and keep my palette and brushes in my hands. I even built the switch out of recycled, weather proof plastic. It even looks good - at least to me. I just need to find a new, old Canon camera. This is just a little hurdle and I will still get this fun little project to work.