After measuring the shutter speed of my DSLR (last month) I started to wonder what else I could I measure with Blinkenlight shield. Then it occured to me that the same technique I applied to power grid monitoring would apply to video frame rates as well. So I basically copied my old code and added some additional flexibility for dealing with different frame rates.
As you will see in the detecting frame rates experiment my DSLR is somewhat off the mark. When I test it at nominal 30 frames per second it is off the mark in a somewhat strange way. Now I wonder if this is on purpose or just by coincidence. If anyone of my readers has digital cameras that can film 30 frames per second I would like to learn what numbers do you get? In order to copy this experiment 2 LEDs are actually sufficient although it works better with more LEDs (and best with 20). What are your measurements?