To capture an instant on film or sensor with a camera, you usually need a fast shutter. But alternately a flash can be triggered with the scene in the dark and the shutter wide open. It’s this latter technique which PetaPixel are looking at courtesy of the high-speed class at Rochester Institute of Technology. They’re using a cheap sound sensor module and an Arduino to catch instantaneous photographs, with students caught in the act of popping balloons.
High speed video is everywhere these days, but the cameras and necessary equipment is a bit out of reach for a hobbyist. [Bassam] found a compromise and came up with a way to shoot high-speed photographs using a sound triggered flash.
Continue reading “Sound Activated Flash For High Speed Photography”
Here’s a flash trigger with a programmable delay. These triggers are often used to capture quick events like a balloon popping. The technique takes place in a dark room with the shutter open. When the event is triggered the flash illuminates the scene and an image is captured. Because these require precise timing it has typically been a chore to synchronize the event, hence solutions like using a pressure plate.
This build, which centers around a PICAXE 08M, allows the photographer to use any trigger they desire, but adds a delay. The box above shows the apparatus set up for a 42 millisecond delay. So if you’re using the sound of the balloon pop as a trigger, you can hold the flash off until the event really gets going.
[Thanks Two Part Epoxy]
Reader [Adrian] picked up a couple cheap wireless flash triggers on eBay. Unfortunately, his Sigma EF-500 DG Super strobe doesn’t have the necessary sync port to make use of these. He popped the device open to try to figure out a way to trigger the device manually. The first idea was to use the test button to fire the device. Thanks to lag, it didn’t work for anything under 1/20th. The solution was to go straight for the optical trigger. [Adrian] has posted some teardown pictures that will help you determine the appropriate solder points for your own mod. The only bit that’s left is adding a 3.5mm mono headphone jack as a sync port. He also has a post on modifying the flash for greater head movement.
