Canon 40D Shutter release cable
I have a Canon 40D which uses a proprietary N3 connector. I already had a Canon RS-80N3 shutter release cable but since it was expensive I did not want to destroy it. Instead I bought a cheap compatible release cable for about $5 and put a 3.5mm plug on the end.
The shutter release is basically a couple of contact switches. Connect the focus pin to ground and the camera focuses. Connect the shutter pin to ground and a shot is taken.
For this particular cable; white is ground, red is +3V shutter release and blue is +3v focus. Other makes will have different colours.
For the camera and flash connectors, the dropController uses standard 3.5m sockets and plugs. I chose these because they are very common and very cheap.
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