Picture-Axe, Sound trigger to camera flash

Photography is one of my many interests. I bought my first DSLR 12 months ago, and have experimented with it a lot.

I came across some nice high speed pictures and wondered how they managed to take them so I did a little research.

Because of the limitations of the moving parts in a DSLR high speed images are commonly taken with a long shutter speed in a dark environment with a fast flash.

First I tested this technique with a mechanical switch (microswitsh) mounted to a plate. I fired a soft air-gun trough a light bulb so that the bullet hit the switch (after passing trough the light bulb)  and fired the flash.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(soft airgun bullet fired trough a light bulb on to a micro switch witch triggers the flash. You can see the bullet when it bounces back from the switch befor the switch has ben fully triggerd)

I got a satisfying result, but I wanted to be able to trigger the flash on other events such as water balloons bursting, objects hitting the ground or colliding in air etc.

Sound seemed to be the logical choice, and google led me to some basic circuits for triggering flashes with sound, but I wanted to be able to control the delay and sensitivity and have different modes and functions. Thanks to LMR I new the solution. Microcontroller!

So I started boarding and building. Thanks to Frits "start here"-link and picaxe 28x1 wiki I was familiar with the 28x1 and happened to have a spare so I was off to breadboarding.

I just copied the Sound detection circuit from picaxe's webpage and added some small modifications. (http://www.rev-ed.co.uk/docs/picaxe_sound.pdf)

Added a serial LCD. And started working with the code.

I hacked a cheap camera flash shoe so that it has a 3.5mm cable jack insted of a pc-sync cable. A 10 cm ling Pc sync cable is 10 times the price of a 150 cm 3,5mm cable.

There is a unused 3.5mm jack on the box for future comming functions. Might be a optical switch or a laser switch (gate) or then a camera shutter relese so that I for example could use this box for making timelapses. Currently Im using a graphical calculator for that.

 

inside Picture-Axe

I have a Brain circuit, a Sound Detecting Circuit and a sensitive gate SCR to trigger the flash. The picaxe is not overclocked (running at 8MHz). The box has a 3.5mm jack for a picaxe USB download cable so it is easy to program more. The code is now about 400 rows (basic) with alot of white space. alot of code is taken up by the menu system. I will try to make some kind of strobe funktion to,

 

EXAMPLE PICTURES

 

 

Hitting a cup as hard as I can (0 delay).

 

Another testshot

Me and my friend had a greate time playing with Picture-Axe

 

Smashing apples. (Eliminateing all signs of atumn)

End of lightbulb

My Picture Axe.

https://www.youtube.com/watch?v=YqFpkZSyrwY

HiGreat post and good

Hi
Great post and good build.

I built something similar only I used an Arduino as I had never heard of the PICAXE then. That was the first thing I ever built with a microcontroller. I used photo transistor and a laser pen as the trigger.
Sins then I have built different things related to photographic work, like this one https://www.robotshop.com/letsmakerobots/node/16230 or this one https://www.robotshop.com/letsmakerobots/node/16315

Great work Renkku!

Good work

Good work and really nice pictures.

Keep it up!

 

Beauty!

Really cool pictures you took there! And this box looks neat as well. Do you have estimate of reaction time? Recently I’ve been thinking of similar project, but using uC and LDR to capture lightnings, but I’m not really sure it will be fast enough…

Geir, maybe you already have some info with ergards to this??

I never did any timing test

I never did any timing test on my trigger as I didn’t have the equipment to do so, but its fast and interrupt driven on the Arduino.
The reaction time from the time the laser beam is broken until the Arduino kicks in is probably in the microsecond range. From that you can set the flash delay in microseconds or milliseconds.

I probably should make a post on my trigger as well, but I haven’t got the time right now.

Here some pictures taken with my system.

dr__pe1.jpg

Looks like I will be doing

Looks like I will be doing some tests whenever I have some time for it :slight_smile:

Wait a sec…

Damn, with the custom characters making up the camera icon? Really? This is a bunch of too-muchery.

And we all now who I have to

And we all now who I have to thank for learning me about the custom characters! :wink: Thanks Chris!

(https://www.robotshop.com/letsmakerobots/node/5276)

I don’t dare to estimate how

I don’t dare to estimate how fast it can trigger the flash, or even where the bottleneck is but its pretty fast. If you want to make small delays you can always move the mic a couple of inches so it takes a longer time for the sound to travel to the mic.

I can’t believe you looked that up.

And I can’t believe how long ago that was… Did you see walter there with the bare frame and square head? Man…

Whats that robot in the

Whats that robot in the background of the last picture?

Yes, I do have the same

Yes, I do have the same question. BTW, nice build and your Picture-Axe is on Make:Online, congratulations.

The robot in the background

The robot in the background is RP-01, my first robot. I have started to make a blog entry of him, but I have just been too lazy to finish it. He has been ready for over 6 months. :slight_smile: I promise to publish him in the near future.

Well here it is! :slight_smile:

Well here it is! :slight_smile: finally!

https://www.robotshop.com/letsmakerobots/node/13249

Coooalh!

Coooalh!

Dude, what’s with all the

Dude, what’s with all the astetics? Just hammer some apples and stuff, man! :smiley: