Whats the refresh rate of the sign?
813 hz. The way the sign generates variations in intensity levels demands that the screen refresh rate be high. Each LED on the sign has 16 levels of brightness. The brightness levels are achieved by illuminating or not illuminating an LED over the course of 16 frames. When I was first figuring out how to come up with brightness levels I decided that the refresh rate must be high enough that at the lowest intensity level (LED on once every 16 frames) the LED would not appear to flicker. This means if an LED is on for one frame every 16 frames than 1/16 * refresh rate would have to be greater than the eyes persistence of vision frequency of 30hz. So: (1/16) * refresh > 30 or refresh rate > 16*30 = refresh rate > 480hz. At the lowest intensity level, I dont directly see any flicker on the sign. Sometimes when Im working on the sign and the majority of the LEDs on the sign are at the lowest intensity level I sometimes think I see flicker out of the corner of my eye but Im not sure if this
