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Floating Water
April 12, 2012 12:01 PM   Subscribe

Making water appear to levitate usually requires a strobe light to trick the eye. If you don't have a fancy system to control water flow, you can run water through a tube taped to a speaker playing very low frequency sound, and again use a strobe light to make the water appear to defy gravity. Or you can ditch the strobe, and sync the sound waves to the frame rate of a video camera to make water drops appear to hover.
posted by filthy light thief (15 comments total) 25 users marked this as a favorite

 
Or you can take some of these here magic pills that I have and the water'll just, like, float maaaan...

(unsnarkily: really neat-o vid, flf)
posted by item at 12:08 PM on April 12, 2012


Are there more videos of water effects using the camera's frame rate?
posted by joelf at 12:20 PM on April 12, 2012


Until he sticks his hand in there and it cuts off his fingers. You people and your "science" scare me.
posted by Big_B at 12:25 PM on April 12, 2012


joelf, I looked for more, but I didn't find anything. I also included most of the good stroboscopic videos I found, as most videos trying to capture the effect show how easy it is to really mess up the visual effect due to unsynced strobes and video recording speeds. I also looked for more in-depth tutorials on how to set up your own strobe show, but found nothing useful or interesting.

The one good looking video I didn't include was this weird demo video for antigravity waterfalls, which purport to actually defy gravity.
posted by filthy light thief at 12:32 PM on April 12, 2012


Levitating water
posted by ShutterBun at 12:32 PM on April 12, 2012 [3 favorites]


Note that the original strobe apparatus bears the euphonic name The Remarkable Double Piddler Hydraulic Happening Machine.
posted by nonane at 12:48 PM on April 12, 2012 [1 favorite]


Found something cool on the web? Yup!

Thanks!
posted by Scientist at 1:00 PM on April 12, 2012


Using strobes or synching frame rates is much too complicated. All you really have to do is just let the water float freely by itself, though this doesn't work everywhere.
posted by twoleftfeet at 1:36 PM on April 12, 2012


Note that the original strobe apparatus bears the euphonic name The Remarkable Double Piddler Hydraulic Happening Machine.

When Doc Edgerton showed it to me, it was just The Piddler, only one stream. I told him I read his new book and thought it was so cool, I built a Piddler last semester in my high school Physics class.

Apparently this was the standard demo Doc gave to all visitors to his lab. And I rushed right to the punchline. Visit over, oops.
posted by charlie don't surf at 1:38 PM on April 12, 2012 [1 favorite]


In the olden days we did this with movie cameras and wagon wheels.
posted by weapons-grade pandemonium at 2:27 PM on April 12, 2012


Very cool, but you forgot to add "MLYT" to your post!

I keed.
posted by MattMangels at 2:37 PM on April 12, 2012


What's happening at 1:48-1:57 of the last link? The droplets appear to go crazy, as if the frame rate is somehow out of sync with the periodicity of the water, and then it corrects somehow? Explain it to my feeble brain!
posted by jcreigh at 4:41 PM on April 12, 2012


As one of the people who occasionally has to open up the "remarkable double piddler" and fix it (very occasionally; that thing is built like a tank), I'll just mention two things:

1. This whole thing only works because we use a "piddler pump" (a fairly standard peristaltic water pump) that is synchronous with the power mains and spits out reliable 60Hz droplets.

2. Always add a little bleach to your piddler water, because seriously, cleaning the mold out of a piddler is horrifying.
posted by range at 5:55 PM on April 12, 2012 [3 favorites]


jcreigh, I'd assume something interrupted the flow of water momentarily maybe a drifting hair landing in the pitcher or something.

The pumps that put out consistent drops I can understand, but I can't understand the uniformity of a gravity fed hose that is attached to a speaker and is vibrating. I understand that is where the shape of the water in the air comes from but I can't believe that the majority of the individual drops are so uniform in size shape and position. I figured there'd be too much randomness involved in a system like that as far as when and how the surface tension forces take over.
posted by Phantomx at 6:41 PM on April 12, 2012


cleaning the mold out of a piddler is horrifying.

I am fully prepared to take your word for it.
posted by ShutterBun at 8:08 PM on April 12, 2012


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