Introduction: Arduino Camera Flash Control

Picture of Arduino Camera Flash Control

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

Picture of Go Get Stuff

You will need:

- Arduino
- Camera Flash (with input jack)
- Breadboard
- MOC3021 optocoupler (Triac)
- 220 ohm to 1K resistor
- 3/32" mono plug
- Solid core wire

Step 2: Wire the Plug

Picture of 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

Picture of 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

Picture of Plug It In

Insert your plug into the trigger port on the electronic flash.

Step 5: Program and Go

Picture of Program and Go
Program the Arduino with the following code:
Assuming that your flash is turned on, it should now be triggered every 7 seconds.


PabloF8 (author)2017-09-21

How fast can go the flash? 1 per second? 10 per second? Is it there a limit?

randofo (author)PabloF82017-09-25

It depends on the reset rate of your specific flash unit. I have not use this specific flash in a while, but I imagine it around every one or two seconds to give them capacitor a moment to recharge

Kay O.S (author)2016-08-03

Hi Randofo! Thanks for this tutorial. I've been thinking of making some complicated photo flash setups and this might just be the ticket to making them happen.

One question, as I'm a super noob when it comes to Arduino, how many flashes could one control from one Arduino? Assuming I want independent control of each.

P.S.: Noticed you got the flash from the store I work at. ;)

randofo (author)Kay O.S2016-08-04

13 - 18. If you get an Arduino Mega, then you can control about 50.

You could also get other chips to interface with the Arduino such as a shift registers, and this would allow you to control even more. However, this is a bit more of an advanced topic.

malixlizard (author)2012-08-17

I am trying to build this but would like to order the parts through a particular website, will any optocoupler work? or can i use a transistor maybe? THANKS!!

randofo (author)malixlizard2012-08-17

I know this one works. It may not work with other types. You can perhaps test and see. Not all optocouplers have the same switching mechanism inside.

malixlizard (author)randofo2012-08-17

Ok i am reading everything i can find on optocouplers and continue to be baffled, the ratings on the couplers seems to be about 1.25v yet the arduino will output a HIGH of 5v, so how is your system not failing? Not criticizing your design just trying to understand and obviously something is not clicking for me, thank you!

randofo (author)malixlizard2012-08-17

You are basically powering an LED. You will need to add a resistor in series with the photodiode in the optocoupler.

dannye90 (author)2012-06-18

Maybe this is a stupid question.. but what does the 'to 1K' part of the resistor measurement mean?

randofo (author)dannye902012-06-18

1,000 ohms

dannye90 (author)randofo2012-06-21

oh. So it can be any value between these?

randofo (author)dannye902012-06-21

You are basically just adding a safe level of resistance before an LED

randofo (author)dannye902012-06-21


dasigi (author)2012-01-13

The trigger port baffles me, I have not seen one on any flash! Would it be possible to create an alternative, for example, with an off-camera shoe mount or some such?

randofo (author)dasigi2012-01-13

You can buy hot shoe to PC flash sync cable adapter mounts.

ynze (author)2011-09-24

Pretty neat! The search for unintended use for a flashlight starts here...

About This Instructable




Bio: My name is Randy and I founded the Instructables Design Studio. I'm also the author of the books 'Simple Bots,' and '62 Projects to ... More »
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