Another good shot that isolated the individual pulses (although they get hard to count at either end since the exposure started with me not moving the camera (I swept from top-right to bottom-left, you can tell from the flash illumination)). Interestingly, the faster I move the camera, the redder the streetlight becomes. This is 1/4 seconds. There should be 30 pulses. The point dots on the right are probably license plates or glints on car bumpers when the flash fired, so they didn't streak.