Add an External Trigger Port to your Camera Flash

Hey folks,

So, for people who are seasoned in photography, you'll probably know that when using Speedlite flashes on consumer-grade cameras, the camera can only synchronize the flash up to a speed around 1/160th of a second.  This is a problem if you want to do high speed photography, using an external controller and sensory input (such as a microphone or light sensor) so the solution is to add external flash control, to allow the controller to trigger the flash itself, instead of using the camera.  This mod also allows you to connect your flash off-camera, using a modified hot shoe connector.  It also doesn't compromise the on-camera functionality of the flash.

The modification is quite simple, requiring only a few tools and parts.

Step 1 Tools and Materials

Materials:

• Manual or TTL flash
• 3.5mm mono or stereo jack
• 4" lengths of 24AWG wire
• 1/16" heatshrink

Tools:

• Drill
• 3/32" and 17/64" drill bits (1/4" may work too)
• Screwdriver
• Hot glue gun
• Soldering Iron
• Solder

Comments

[patdoherty]

that weird i did the same exact thing with almost the same flash, i had no idea there was an instructable for it though and i also used mine for high speed photography although i used an arduino to control mine

[gavinzac]

Just so I get this - this will result in a flash that can be fired via the 3.5mm jack E.g. by one of the "EbayWizard" cheapo radio transmitter/receivers?

And still let it then be popped back onto the camera hotshoe if needed?

I get the feeling you intend it to be used for other projects, e.g. sensitive-triggered-in-the-dark high speed flash photograph, but it would also be useful for me to carry around a few less adapters for flash-to-radio.

[mattthegamer463]

If the "ebaywizard" triggers use a 3.5mm connection, then definitely it can work. Obviously you can use any 2+ conductor connection, as long as you know how to wire it up for your specific application. I wired mine for the Camera Axe trigger ports, which use opto-isolators to short the pins of the pins.

This project does not diminish the functionality of the hotshoe, or normal flash operation. I don't recommend having the port plugged in when it is in your hotshoe though, I've never tested that and it could cause an issue.

Hope that helps. You can definitely eliminate all the hotshoe adapters you would normally need for radio flash operations.

[colin353]

Once you get the camera axe going, post some high speed explosion shots!