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View Full Version : So You Think Your Strings Vibrate?



SweetWaterBlue
12-17-2009, 06:46 AM
I was watching one of markocchionero's videos the other night and noticed something weird in the frame where the strings were. I did a stop action and to my amazement you can really see these strings vibrating like crazy. They almost touch each other. It shows up more at the beginning of the video, but here's one of the stop action shots. Really cool.

http://www.flickr.com/photos/smyrna5/4193282218/sizes/o/

Here is the link to the original video - watch those strings go! :

http://www.youtube.com/user/markocchionero#p/u/5/yxKqp2HMu5g

UKISOCIETY
12-17-2009, 06:51 AM
Cool !

spazus_maximus
12-17-2009, 06:53 AM
Thats the freaking weirdest thing i have ever seen....are we sure thats not some kind of video enhancement?

UKISOCIETY
12-17-2009, 07:07 AM
Whoa! Did you see what happens when he really gets going at the end?
http://farm3.static.flickr.com/2792/4193331632_231d00c83b_o.jpg


:rolleyes:

spazus_maximus
12-17-2009, 07:22 AM
nobody even posted any comments about the strings on yt....Am i the only one perplexed by this?

Moore Bettah Ukuleles
12-17-2009, 08:21 AM
That is too wild. I just watched the video. I think it's got to be a video glitch of some kind. Either that or he's playing with rubber bands. It's fun to watch. Thanks for posting that.

Blrfl
12-17-2009, 08:41 AM
It probably has to do with the fact that the original was compressed and YouTube compressed it again.

Cool effect, though.

--Mark

GreyPoupon
12-17-2009, 08:43 AM
I don't think his strings are doing anything unusual it is just an illusion created by an interesting synchronizartion between the frames per second of the video and the vibrations per second of the uku. I think a very low speed camera - creating a moving image from only a few shots - together with a high shutter speed - which would capture high-resolution images - might produce this effect.

Melissa82
12-17-2009, 08:45 AM
Whoa! Did you see what happens when he really gets going at the end?
http://farm3.static.flickr.com/2792/4193331632_231d00c83b_o.jpg


:rolleyes: This is epic.

spazus_maximus
12-17-2009, 08:51 AM
When I get off work first thing im gonna do is boil 4 spaghetti noodles....not sure how I will tie them....but I will figure it out....Then I should be able to play some Django!

thejumpingflea
12-17-2009, 08:59 AM
I think this is some sort of glitch or he has REALLY low tension strings on there.

Too cool of a video though!

thisnthat
12-17-2009, 08:59 AM
Whoa! Did you see what happens when he really gets going at the end?
ROTFL! That's great. :D

I'm going with Blrfl's theory, probably something to do with the video frame rates and the compression.

experimentjon
12-17-2009, 09:50 AM
Now, what about that piece he was playing? I thought that was awesome. I want to play like that! Oh, and the strings were cool too. :D

Doctroid
12-17-2009, 10:01 AM
I'm going with the compression artifact theory. I can't see how physics would produce those kinds of motions, and I'm doubtful the sampling/rastering speed would fully do it.

SweetWaterBlue
12-17-2009, 10:16 AM
Now, what about that piece he was playing? I thought that was awesome. I want to play like that! Oh, and the strings were cool too. :D

I agree. He is an awesome player, and I almost hated to start such a nerdy thread about the stings, when his performance is what I should have been noticing. But unfortunately, I notice things like that. I love the performance too though.

He gives individual lessons on the internet (www.jazzukes.com) by the way using Skype. I think they are like $25 per hour. What a cool idea.

Uke.
12-17-2009, 10:22 AM
Trippiest thing ever.

GrumpyCoyote
12-17-2009, 10:44 AM
You are seeing two things here -

1) The capture rate causing a strobe effect - if you used a timing light you would see your strings wobble too. Not this much though...

2) Software compression / error correction. That exaggerates the effect and makes the inconsistant appearance.

I think it's nifty. I also think I've been staring at it to long and it may have eaten my soul...:(

rpeters
12-17-2009, 11:36 AM
I don't think that's actually what's happening in this video, I think it's an illusion due to the compression of the video. But I'm no expert, so I don't know for sure.

bazmaz
12-17-2009, 11:54 AM
strings vibrate in a wave, which, you guessed it, looks like a wave.

With a stop motion, freeze frame high speed shot, you may well get lucky and catch the shot where strings are waving - especially with compression on vids.

Point is though - all of our strings actually do this as they vibrate - you just done see it.

Its a bit similar to the spinning car wheel that you look at and it looks like it is stopping, then spinning backwards..

buddhuu
12-17-2009, 12:35 PM
I'm with Grey, Grumps and Paul. It's a strobing kind of effect caused by an interaction between the vibrating strings and the video frame-rate.

Vibrating strings certainly do exhibit amplitudes that big, it's just not usually evident to our eyes.

There may also be an element of compression artefact, but that alone wouldn't do it, IMO.

[/best guess]

Big_Fred
12-17-2009, 01:26 PM
I imagine it may have something to do with a strobing effect due to the camera.

Here is a link to an interesting IPhone phenomena taking pics of a plane propeller:

http://scalarmotion.wordpress.com/2009/03/15/propeller-image-aliasing/

Same thing could happen with uke strings in a left/right shutter config.

SailorQwest
12-17-2009, 02:04 PM
This is what happend when I moved while taking a pict with my iPhone.
I use it for my iPhone wallpaper.




http://i286.photobucket.com/albums/ll105/sailqwest/de93fc78.jpg