DIY Remote Trigger Debuts

Are you too geeky for PocketWizards?

Did you win your 8th grade science fair?

Do you know what an "opto-isolator" is?

Then you are a prime candidate for SPOT, the Strobist Project Open-source Trigger. Started quite a ways back, it has finally taken form -- along with a pretty cool case, as seen in this photo.

Features, specs and link after the jump.

Here it is with no clothes.

Mad props to Till Seyfarth and all involved in this very impressive project. Next up, they will be showing you how to build a home-brew SB-800 for just $56.

(I wish....)


• Synchs at up to 1/250th of a second
• Approximately 30-meter range
• Triggers through walls and windows
• 4 groups of adjustable flashes
• Remote power level adjustment for "old" flashes (e.g. SB-24)
• Cost of parts ~ €50
• Open source software

(Full info, schematics, wiki, source code, etc., here.)


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Blogger Rolando said...

Wow, mind blowing! I'm a software engineer myself and a fan of open source software and never thought about open source hardware. This is awesome, --congrats!

April 09, 2009 11:06 PM  
Blogger Rams said...

Wow - cool post. Useful for the experimenters out there.

I know there are going to be many Strobists who are going to really enjoy this post !

In London, we've got quite a few geeks .... sorry I mean tech aficionados :-)

On D.I.Y. Triggers ..
Trust me - nothing beats something produced by a company.

When your shooting day in and day out, when you need something to work - that's when quality and workmanship matters.

April 09, 2009 11:45 PM  
Blogger Kevin Halliburton said...

Fantastic! I had given up on this project long ago. I'm going to have to dig in and see if I can make a go of this. Even if I come up short I feel like we all owe a huge thanks to those who poured so much time and effort into developing this for the Strobist community.

April 09, 2009 11:59 PM  
Blogger magullo said...

Well, being a (newbie) photographer, a strobist fan, a DIY aficionado and an arduino geek, this post is simply the summa of all my passions.

April 10, 2009 3:14 AM  
Blogger bakrihafizhisham said...

this is nice!

April 10, 2009 5:02 AM  
Blogger Jeffrey Byrnes said...

I have often wondered how simple/complicated it would be to produce your own wireless trigger/receiver system. Now I know. Thank you.

Great stuff...

April 10, 2009 9:11 AM  
Blogger gem said...

hi, i'm a long time reader/ lurker.

this is a great idea! i was just getting frustrated with all the new eBay triggers flooding out this 2009, this will make things less complicated.

this will probably take a year to complete though, but i'm very confident it will be done, the Lumopro seems to be a very well made "open source" product, and this one looks like it's gonna go that path too.

while this great project isn't done yet, i created a page for people who might want a guide list of the different product names of the new ebay triggers that came out this 2009, and photos of what they look like.

it's just a simple page with the product names and photos, just to cut through shoppers' confusion.

April 10, 2009 9:47 AM  
Anonymous Alan Lapp said...


Congratulations to all who participated in this project! A project is well and good, but a FINISHED project is a thing of beauty.

I'm definitely geeky & DIY, but my understanding of electronics is incomplete at best, so I have extra admiration for your strong kung fu. Again, well done.

April 10, 2009 11:24 AM  
Blogger Keith Race said...

Oh man! I'm gonna have to bust out the soldering iron and relive grade 10 electronics... that's a loooong time ago.

This is amazing!

April 10, 2009 12:28 PM  
Anonymous Anonymous said...

kudos to saying meters

April 10, 2009 1:00 PM  
Blogger abritinthebay said...

Some points to note about this kit -

currently (according to the docs) it only suports one camera - a Sony. Bleh.

Also only supports one type of Nikon Flash. Again, bleh.

However - I'm not saying this isn't an awesome idea :) Just remember it has limits *at the moment*

April 10, 2009 3:35 PM  
Blogger rich said...

I think this is awesome and the start of a mass production company for cheapo pocket wizards with LCD's. Good work people!

April 10, 2009 4:18 PM  
Anonymous Peter Wine said...

A few years ago I would have jumped on this, but these days DIY electronics isn't something I have the time for.

So I will admire from afar (for now) the fortitude it took to complete this project.


April 10, 2009 5:22 PM  
Blogger Tim B said...

What a great project! I love experimenting with this kind of electronics project!

April 10, 2009 8:32 PM  
OpenID realitytourist said...

I don't think it ONLY supports the Sony camera or the two Nikon flashes. I think those were in the basic requirements of the project, which to me, shows an important point: it works cross-platform.

I know how to use a soldering iron, but I like real complete instructions. The post implies this thing is ready to build, but I don't see everything there yet. Is there more to be found?


April 10, 2009 11:24 PM  
OpenID dialachineduphotography said...

Hey Dave,
This is great news to me and every strobist...since i joined this movement less than a year now, I see growth EVERYDAY in strobism, my photography and the photography of fellow strobists...You have no idea what you've done by starting this see a basic blog grow into something followed by people around the world and now we have our own DIY trigger...I guess there are no just keeps getting better and better...My prediction is that one day the word 'strobist' will be added to the dictionary but its just that we maybe too old then or we may have already left the earth's surface...but this movement will NEVER die...

Again, congrats to you and everyone who were crazy enough to come up and work on an idea for a DIY remote trigger!!! This is the perfect 3 year anniversary gift IMO

April 11, 2009 12:09 AM  
Blogger tim10243 said...

this is nearly exactly what I am looking for - a radio based flash trigger which is able to control the manual flashpower. And all this for a very good price!
After reading the docs I still have some questions:
- Is the trigger working only with a Sony camera and not with a Nikon D3, D700 or D3X?
- I got some SB-24, SB-25 and SB-28DX, but you mention just the SB-24 and the SB-26. Will the trigger not work with the SB-25 and SB-28DX?
- How is the flash conected to the trigger? Don´t you need a special Nikon hotshoe for it to conect to the controlpins at the speedlight?
- Looking for the modules you take for this construction I found another radiomodule, the RFM12BP which has a range of more than a kilometer. Would it be possible to use this radiomoduke as well?
- I read about a minijoystick which you use at your construction but I cant´t see it at the picture. Would a be possible to publish a few more picturs of your "prototype"?
- For a greenhorn like me it could become a little hard to find all the components you use. Would it be possibel to publish a list of dealers which offer the things you need, especially the case for example?
Thanks a lot for this open source work.

April 11, 2009 6:18 AM  
Blogger Andrew said...

Compatibility - It doesn't operate in TTL mode with the camera, it should work with any camera.

As to flash compatibility - It has an active low trigger output and an active low quench output. It should work as a basic trigger with any flash (Some of the old high voltage flashes might fry that optocoupler on the output, I haven't looked in enough detail in the design, but that's easy to fix. I would guess the opto has pretty high voltage ratings to begin with though.).

The remote power control feature requires a flash with a quench input. Most "oldschool" TTL systems worked like this. The only problem is that I think some systems used an active high quench, while others (including Nikon) used an active low quench. Using it with other systems that have an active low quench input is a matter of shoe pinout.

Yes, the RFM12BP could potentially provide HUGE range increases.

I'm guessing that a Sony camera and a Nikon flash was what the main project designer had to test with and absolutely required compatibility with, but I see no cases where compatibility with anything else was explicitly sacrificed. (Testing with other equipment might of course reveal some corner cases where some things fail.)

April 12, 2009 12:10 PM  
Anonymous Anonymous said...

hi i realy love the idea of building something myself but since the ebay cactus triggers are so damn cheap its no real option


if there was a ettl solution (not spending 300 on pocketwizzards)
i would be building nonstop

April 13, 2009 6:28 AM  
Anonymous tim10243 said...

I don´t think that cactus is a real alternative to this triggers. These triggers are the only ones I know which offer remote power adjustment for old flashes like the SB-24. These old stuff is cheap to get but you always have to go to all of you flashes to make a new adjustment if you use simple triggers like the cactus. The only alternative I see would be the Radioppper JRX if they ever start to sell them. The JRX ofers a remote power adjustemnt for Alien Bees - if someone would be able to make this remote adjustment work with other flashes (like the SB-24) too, the JRX would be an alternative - also with its prive of 50 USD.

April 13, 2009 10:28 AM  
Blogger shinydistractions said...

Andrew, the MOC3041 is rated for 400V. I'd fear for the jack first.

tim10243, as I understand the X system, you can stick a PX receiver on your choice of flash and control it manually with the knobs on the JrX transmitter, so long as the flash supports manual power change over IR.

Most of the items should be available from the usual online component distributors (Mouser, Farnell, Digi-Key, Avnet, etc.). The one odd duck is the radio module, which looks to be available only as samples from the manufacturer in China. If someone in the US wanted to order up a bunch of these and repackage them as singles, that'd be wonderful.

To be frank, the low cost and imminent release of the JrX has me less than enthused about trying to DIY a roughly equivalent device for roughly the same price. As cramped as my time is right now I'd probably make actual use of the JrX months sooner.

April 13, 2009 8:38 PM  
Anonymous Anonymous said...


NOW, you see, we have Opportunity...

for open-source Battery Powered Monolights!!

Here's the idea
( I'm not an EE, but love making stuff :)

Make a plain strobe circuit, with these differences:

1. powered by NiMH D-cells, for freedom-from-linepower, & oomph.

2. monolight tube, instead of the little hot-shoe flash tubes ( some companies sell spares/replacements, so you can find 'em in the bigger stores )

3. a switchable bank of capacitors:

All-Four/Eight-Together, or
( for faster apparent-recycle-time, for sports shooters -- 3 charging while 1 is firing, or 7 charging while 1 is firing, see... :)

That, combined with a slight modification of this remote, and you've got remotely-controllable BIG power or fassttt-cycling.

I know others are capable of going from an old stobe to a completely new circuit, while knowing what they're doing, and I know that I'd probably get killed trying to do that, because the math I can't do.

However, somebody please make such a design & partslist for us who wanna try making stuff to exactly suit us...

Freedom rocks, man...

( :

April 13, 2009 11:01 PM  
Anonymous tim10243 said...

I just got a mail from radiopopper which described it the other way round. They say you´ll need a PX transmitter and JRX receivers to make manual power adjustments at remote speedlights. I guess they mixed it up and you are right.
Anyway: the JRX transmitter and the JRX receiver are able to make a manual power adjustement at alien bee studiolights ( ). If someone here would be able to design a possibility to adjust SB-24s and other old Nikon speedlights too, that would be it!

April 14, 2009 2:00 AM  
Blogger chris said...

I've been thinking about building a studio flash from scratch, just for the fun of it and because I'm curious.

anyone else had that thought?

Maybe we can design an open source public domain flash system?

I'm game for smaller flashes as well. I just happen to know that PerkinElmer sells photographic flashtubes (QXA series is populare) for studio flashes and i know where to buy them.

January 07, 2011 8:31 AM  
Blogger recwap said...

---- APCCS ----
DIY arduino based open source advanced photo camera control

CPU 16Mhz Atmega 328
84x48 graphic LCD
IR Trigger & Wire Trigger photo camera trigger
2x Wire Flash Trigger
onboard light/sound sensor or 2x external sensor
2x digital IN/OUT
timelapes function
onboard RTC clock
onboard buzzer!/pages/APCC-Advanced-Photo-Camera-Control/194425487264052?sk=info

March 23, 2011 5:13 AM  

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