Hello everyone. I am brand new to Arduino so sorry if this is the wrong area to post this, please point me to the right area if so.
I am trying to replicate the remote trigger switch for my Panasonic GH1 camera. The electrical schematic required is basically two switches that change the resistance seen by the camera. See the following website to see the schematic: Panasonic Lumix G1 GH1 Remote Shutter Release Circuit - Robot Room.
I want to use my Arduino UNO to remotely trigger the camera every few seconds to put together a time lapse video. Eventually this will hook up to a small rolling cart that will move slowly along taking pictures every 30s - 1min to produce a nice photographic video effect.
This one has two optoisolators in one chip: http://www.digikey.com/product-detail/en/LTV-826/160-1362-5-ND/385832
It allows you to control two switches using two Arduino pins.
I don't know if you need to control the inputs individually but it's nice to have the possibility to do so.
With relay contacts (which are switches) you don't have to take any polarities (of the circuitry getting switched on) into consideration.
You need to have a diode across each relay coil, too.
Opto isolators will probably work in that circuit, but it's not completely clear because the camera is measuring changes in resistance, so the saturation voltage of the opto isolator might cause a problem.
I would use two reed relays. You can drive them direct from Arduino pins (don't forget the diode in parallel with the coil), and unlike normal relays, they are silent (which is important if you are trying to photograph wildlife).