It’s simple because cable releases are simple devices – they usually have two contacts: a focus contact and a release contact. Closing one contact will trigger the internal focus mechanism and closing the other contact will release the shutter. In fact, its so simple that you can make one from a dead mouse.
What release cables usually lack is brains. I mean they will trigger a camera when you tell them, and some o the mode advanced models even have HDR, BULB and timelapse modes, but they cant act upon external events. [Read More…]