After having fun with some infrared and macro photography I wanted to try some time lapse. Some cameras have built in intervalometers ( big word for interval timers ) which allow you to do time lapse with little effort. Sadly the Canon Rebel XT does not, so I searched around for solutions, most of which are quite expensive.

I found out some useful information:

• the Rebel XT has a 2.5mm stereo jack connection for remote operation
• connecting the ring and base of this jack trigger the autofocus
• connecting the tip and base of the jack triggers the shutter

With this information I hacked together a makeshift solution with a 12v relay, 12v wall adapter and an X10 appliance module. This system sucked and wasn't portable, but it was all junk I had laying around. Anyhow, I went back to searching and found out about the TC-80N3, a Canon wired remote which does all sorts of fun timer stuff, including time lapse and goes for under $100 on eBay now and then. Unfortunately it doesn't work with the Rebel XT, the connector is different, out of the box at least.

I found out that it has three leads on the connector, as the Rebel does, so perhaps they function the same? It seemed to be the case so I went and purchased one, hoping to just swap the connector out.

Once it arrived I went straight to hacking it up. Chopped off the old connector, found out that there are two wires and a ground wire, sweet. With the help of my multimeter I determined that the red wire is the shutter and the white wire is the focus. So, to attach the new connector:

• solder the red wire to the tip of the 2.5mm jack
• solder the white wire to the ring of the 2.5mm jack
• solder the ground to the base of the 2.5mm jack

Slip the cover back on or tape up the connector, whatever, and it's all done. The Canon TC-80N3 modified to connect to and control a Canon Rebel XT. Doesn't need much know how at all to pull this off.