Monday, September 12, 2011

Remote Camera Trigger for DSLR

Here's a quick one. The remote triggers of many cameras (including mine - Canon Rebel XTi) work on a very simple mechanism. The trigger socket accepts a normal 2.5mm TRS (audio) pin.

The pin connections are as follows:
  • Tip is for expose function.
  • Ring is for focus function.
  • Sleeve is connected to ground. It is common for both expose pin and focus pin.
To activate any function, connect the corresponding connector to ground (sleeve), that's it!

Here's how I built a simple remote with focus, expose and long expose function for bulb mode.

  • PCB mount push button switches with long stems - 2 numbers.
  • PCB mount toggle switch - 1 number.
  • Perforated board.
  • Old headphone with a good cable.
  • Feviquick - quick acting adhesive that bonds plastic/rubber.
  • M-Seal - epoxy resin putty for covering the stuff.

  • Cut off the ear pieces from the headphone wire and strip the edges. You should find two strands of conductors in each of the wires that went into the ear pieces. Identify the ground wire (usually gray color), the tip wire (usually red in color), and the ring wire (usually green). Use the multimeter to verify the connections.
  • Cut off a thin strip of the perforated board that can fit your switches. Keep a bit of spare length. You'll need it to fix the wires later.
  • Mount the components and solder them. Solder the headphone wires at the end, and be easy with it as the wires are very delicate. Pictures below show how I laid them out.
  • Fix a small portion of the headphone wire on to the PCB with Feviquick so that it does not flex near the solder point.
  • Test it once with the camera and the multimeter to ensure it's working and there are no loose connections.
  • Mix the M-Seal putty and cover your creation fully sealing it. Make your favorite shape as you like it. Mine looks like dog poop. :)
  • Wait until it hardens. Spray on a rubber coating if you have it. Enjoy clicking!

This should be equivalent in function to Canon Remote Switch RS-60E3. Hence it should be compatible with all the models listed with that product. I'm just replicating the same list here for convenience:
  • Digital Rebel XSi / XTi
  • EOS 60D
  • EOS Digital Rebel
  • EOS Digital Rebel XT
  • EOS ELAN 7 / 7E
  • EOS Rebel 2000
  • EOS Rebel G
  • EOS Rebel G II
  • EOS Rebel T1i (Body)
  • EOS Rebel T2
  • EOS Rebel T2i
  • EOS Rebel T3
  • EOS Rebel T3i
  • EOS Rebel TI
  • EOS Rebel X
  • EOS Rebel XS
  • EOS 350D
Many other Canon and Nikon cameras have similar mechanism, but different connectors. The same circuit would work, as long as you can get the right connector cable. If you are not sure, ask a camera mechanic or search on the internet for pin connections before you tinker with your camera! I'll post updates for other cameras, if and when I get the opportunity to try one out.

Afraid to get your hands dirty?
Will be glad to help you start if you are a photographer but would like to tinker a bit. I can also make one for you, if you don't like to get your hands dirty. Just leave a comment with your request and I'll get back to you.