DIY Sound-Activated High-Speed Photography 106
eldavojohn writes "Have you ever wanted to catch the perfect photo with your SLR camera but couldn't time the shot just right? Photography enthusiast Matt Richardson brings us an instructional video over at Make Magazine that shows how to use some very basic breadboarding and an Arduino Nano to do some high-speed flash photography that is timed by sound instead of your finger hitting the button on the camera. He pops a balloon and smashes a wine glass to show some results. His code is available on Github, and you can find more of this sly hardware hacker on his YouTube channel."
Re:OK (Score:3, Interesting)
Oh, you mean your camera doesn't run Linux. How odd
I used to have an HP dig cam that allowed you to write programs against a public API, that you could load into the camera via the CF card and then run from the camera.
I saw this done in the 70's! (Score:5, Interesting)
Back then, a similar project used op amps to trigger a flash unit. It was an article in one of the electronics mags I saw back in the late 1970's, titled "Build the Thunderbolt". (I Googled it, but came up empty.)
You adjusted the timing of when the flash was triggered, by moving the microphone closer or farther from the sound source. You could also have added a 555 timer, if you needed a longer delay than was feasible with a longer distance.
It reminds me of a discussion at the Electronics firm I am consulting for. They needed to add a 1/2 second delay to the startup of a device in a new product. I suggested they add a 555 timer circuit. They looked at me like I had two heads. Their solution was to throw a microcontroller into the product. Come on, guys! It can be done with a 555, a cap, and two resistors. It's crash-proof, too. Whatever happened to K.I.S.S?
Re:OK (Score:3, Interesting)
Seriously, why do we need an Arduino to make a sound trigger?
I agree that the Arduino is overkill for a basic sound trigger - but projects like the Camera Axe [cameraaxe.com] make a lot more sense. I use a variation on the Camera Axe for photographs of lightning among other things.
Re:Quicker Than Sound (Score:3, Interesting)
Seeing how light travels much faster than sound, my initial reaction is that this is a terrible idea.
Didn't bother viewing the linked video, eh?
The idea works pretty well because things with mass tend to move slowly, so despite the latencies involved and differential speed of sound and light, the described mixed digital / analog device works quite well to capture a mid-pop baloon or breaking wine glass. But then there are all of those classic Doc Edgerton photos that were taken with just analog circuitry, and they worked fine, too. Indeed, Prof. Edgerton made quite a career for himself at MIT using just this idea. So, despite the perhaps 10 seconds of thought you put into the problem before composing your negative reply, the idea has merit.
need for copylefted educational photos (Score:4, Interesting)
Re:OK (Score:3, Interesting)
Discrete components. Google for "sound trigger" and you'll see how easy it is to build one out of an opamp or even 2 transistors and a few resistors.
Re:OK (Score:5, Interesting)
I did this in the 1970's for a photography project using an SCR to handle the high strobe trigger voltage (used to be ~160 volts on the shutter contacts) and the amplifier from a portable tape recorder to amplify a microphone to enough voltage to trip the SCR. With a strobe mounted off the camera and the camera on bulb setting, I took pictures of light bulbs crashing onto the sidewalk. Due to the lighting angle, most people thought it was taken in the daytime in sunlight. I adjusted the delay after impact by changing the distance of the mic from the bulb. 6 feet provides a good delay. With the mic too close, the bulb looks like it is sitting on the sidewalk with a few cracks in the glass. The delay was necessary to get the bulb in a reasonable amount of shards.
Re:OK (Score:3, Interesting)
Seriously, why do we need an Arduino to make a sound trigger?
To generalize your question:
I'll take a stab at it: Because it allows a software developer to do things that previously required a hardware developer (EE), for certain problems. This unbinds prototyping from a certain educational requirement, opening the field to more participants. For one-off projects of value, the cost of an Arduino board may be low enough to be considered negligible.
It's exceedingly doubtful anybody would go into mass-production with an Arduino-based design, unless time-to-market or field upgradability were the ultimate criteria, or the volumes were low enough that hiring proper engineering would not be cost effective.