Principle of electric release:
Most of the cameras have a shooting sequence as this:
Under the release button, there are three connections: com, map, obt
  1. when pressing half way the release button, com and map are connected and the camera memorize the distance.
  2. when pressing fully, obt is connected, and the camera sets the lens, and triggers the shutter.


So, it is necessary , in each camera, to identify these three connections near the release button, and then to connect and install a plug that can be connected from outside..
To release, two wires only  are sufficient because it is possible to connect, after this plug, the map and obt functions. When releasing, the contact will be done with com, which will not impede the camera first to set the distance, the exposure control, and then to shot.
Once the external plug removed, the camera is working as usual.


Olivier Humez set the wire com at the center of the plug. Being symmetrical, the plug doesn't need an index.

Take 3 connectors on a bar 2.54mm step. The female plug is set inside the camera, and the male plug outside.

 See the page mini plugs




female plug                  male plug