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How Fast Is Your Flash?
arduino hacks, camera, digital cameras hacks, flash, LED flash, remote trigger, xenon flash Comments Off on How Fast Is Your Flash?
What’s cooler than learning about timers and interrupts on AVRs? Well, if you’re like [Matt], you can use that learning experience to build something useful – in this case, a timer for various camera flashes.
There are two ways to measure the speed of a flash. The first is the lag between when a button is pressed and when the flash goes off. As long as this is consistent, everything’s okay. The second type of speed is the pulse width. When looking at a xenon flash as time vs. brightness, they have a large spike at the beginning followed by a significant amount of decay. LED flashes are pretty much one cycle of a square wave.
To measure both types of flash speed, [Matt] used a $0.50 photodiode an a 3.5mm mack that ties into the flash remote. These bits are wired up to an Arduino, a little bit of fun work with timers and interrupts happens, and [Matt] learns how fast his flash is.
Filed under: Arduino Hacks, digital cameras hacks