When not mesmerizing with anamorphic pac-man scenes in his home, creating push pin portraits, or making simple and simply amazing animated optical illusions, Facebook user Brusspup is busy turning water into waves. You may remember his similar experiment from this time last year, which he has now followed up with improved camera close-ups. Incredible!
12 thoughts on “Visualizing Water & Sound Part 2”
Comments are closed.
ADVERTISEMENT
Join Make: Community Today
it is the hose that is being affected to create the display.
That’s really amazing!!!!
I wonder whether this would be better / different / smoother if he installed a low-passs laminar flow filter in the water stream (http://blog.makezine.com/projects/laminar-flow-water-fountain/) (http://www.buildmyowncabin.com/landscaping/diy-laminar-water-jet.html)
So 26Hz made it appear to move forward, 25 was still and 23 looked like it was in reverse. Is the frequency of the speaker related to the sample rate of the camera?
I would guess yes, does anyone have more details?
Yes (however, it is 24Hz where it stands still–the frame rate of the video). 48Hz and other multiples would also appear to be standing waves. It is the same effect as propeller blades, tire wheels spinning backwards, and ignition timing lights (or forwards then backwards as they speed up). At faster rates, the water has moved a little forward of the last frame. At slower rates, the water isn’t quite to the same place as it was in the previous frame. The same principle is also how your car mechanic uses a timing light (a strobe light) to set the ignition timing.
If all you have is a 30 frame per second camera, use 30Hz for a standing wave.
I haven’t done the math, but at frequencies up to 50% faster should look like it is moving forward while those up to 50% slower should make it look like it is moving backwards.
Really cool video. Would be curious what it would look like at a normal speed (i.e. without any visual modifications).