This is a simple method for controlling a camera flash using an Arduino. The nice thing about this method is that it uses an optoisolator to separate the Arduino from potentially high voltage spikes produced by the flash. I choose to use and optoisolator instead of a relay because the response time is much quicker, which is important when dealing with split second camera timing. Being able to control a camera flash in this manner is not only useful for Photography, but can come in handy for making a haunted house display (and miscellaneous hijinks).
Step 1: Go Get Stuff
You will need:
- Camera Flash (with input jack)
- MOC3021 optocoupler (Triac)
- 220 ohm to 1K resistor
- 3/32" mono plug
- Solid core wire
Step 2: Wire the Plug
Open the casing for your plug and solder a red wire to the center terminal pin and a black wire to the outer terminal.
Reassemble the casing.
Step 3: Wire It Up
Connect pin 13 from the Arduino to one leg of a 1K resistor.
Connect the other leg of the 1K resistor to pin 1 of the chip (this is the pin next to the dot).
Connect ground from the Arduino to pin 2 on the chip.
Connect the red wire from the 3/32" plug to pin 6 and the black wire to pin 4.
Step 4: Plug It In
Insert your plug into the trigger port on the electronic flash.
Step 5: Program and Go
Assuming that your flash is turned on, it should now be triggered every 7 seconds.