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There’s an old joke where you ask someone what’s the most important thing about comedy. When they get to about the word “important,” you interrupt them and say, “Timing!” Perhaps the same thing can be said for photography. [Ted Kinsman’s] students at the Rochester Institute of Technology would probably agree. They built an Arduino-based rig to do inexpensive stop action photography.

As Arduino projects go, it isn’t very sophisticated. The circuit contains a  sound detection module and an optoisolator. The code would easily fit on a piece of notebook paper. When a loud sound occurs, the Arduino triggers the flash. Simple enough, but the resulting pictures are amazing. It also looks like a lot of fun to destroy perfectly good things in the name of art.

If you are interested in photography, there are enough photos of their setup to give you some ideas about lighting, reflectors, and camera angles. If you are not a photography fan, you still should check out the post to see more of the pictures the students took.

Interestingly, [Dr. Harold Edgerton] at MIT pioneered this technique starting back in 1937 and you’ve probably seen some of his famous photographs like the bullet through the apple or the milk drop crown. He used the same techniques to take photographs of the atomic bomb tests in the 1950s and 1960s.

You don’t have to use sound as a trigger, by the way. We’ve seen lasers do the trick. And while the Rochester group’s build was simple, we’ve seen some even more bare-bones.


Filed under: Arduino Hacks

[Paul] created a frame that uses an Arduino and LEDs to create a slow motion illusion of a delicate item (like a flower or a feather). The effect is striking as you can see in the video below.

[Paul] had seen similar projects (both one-offs and sold as a product), but wanted to do his own take on it. The principle is simple: The device vibrates the objects at one frequency and strobes LEDs at a slightly different frequency (80 and 79.5 Hz, in this case). The difference between the frequencies (the beat frequency) is what your eye perceives as a very slow (0.5 Hz, here) motion.

Once you know the secret behind the device, it is not very complicated to create. The woodworking for the frame is the bulk of the work. An Arduino excites an electromagnet to vibrate the subject items. It also pulses the LED strips to achieve the strobe effect. It’s simple, striking, and a show piece. It seems like everyone has been building their own magic mirror project, but we proffer this awesome concept as the next big thing everyone should try on their own workbench. Let’s check out a few other examples to get you thinking.

One of [Paul’s] inspirations was Time Frame, which appears in the second video, below. You can find its code on GitHub. It also uses an Arduino to create the same effect. The other inspiration was Slow Dance, which we covered earlier. We’ve also seen a similar trick played with water droplets.


Filed under: Arduino Hacks, led hacks


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