When recording video, a camera’s frame rate can produce some pretty strange effects. If matched up with a helicopter’s blades, a helicopter looks like it’s hovering in midair with motionless blades. YouTube user mrbibio found that the same thing can be done with falling water. His technique is brilliant: by pressing a water tube against a speaker, mrbibio was able to control the vibration frequency of the water flowing through the tube. As it leaves the tube and falls through the air, the droplets fall in identical paths and match a multiple of the frame rate of the camera.
(via Gizmodo via Photography Bay)