Now this has gotta interest pickup makers

[Mark Hammer]

Someone on the DIY Stompbox forum linked to this staggering video of bass strings in slow-mo: stunning bass-string shot on Vimeo
Enjoy.

[big_teee]

Cool

[frankfalbo]

It is cool but not indicative of what the string is doing. The rolling shutter is capturing the different parts of the string at different times. It's actually more like that trick you do wiggling a pencil between your thumb and forefinger making it look like the pencil is rubber and bending.

[SteikBacon]

I have seen same effect in real life. Had a tv in the background and were looking at the string between the string and fretboard. The frequencies of the tv and string made this strangelooking effect I had not seen before.

[peskywinnets]

Isn't this just the result of a 'beat frequency' between the low frequency vibrating string and camera's fast shutter?

Cool nevertheless.

[FunkyKikuchiyo]

... Or whenever you've looked too closely at the strings under bad flourescent lighting.

Long live incandescents!

[RedHouse]

Looks like the bass is strung with spaghetti noodles.

[JGundry]

It is cool but not indicative of what the string is doing. The rolling shutter is capturing the different parts of the string at different times. It's actually more like that trick you do wiggling a pencil between your thumb and forefinger making it look like the pencil is rubber and bending.

This is video, there us no mechanical shutter so shutter angle does not come into play. From the point of view of the camera the video is an "accurate" depiction of what the string is doing keeping in mind that the camera shutter speed determines the strobe effect that freezes the string oscillation. The effectiveness of the strobe freeze effect is simply a function of the the shutter speed multiple as it relates the the multiple of the string oscillation for a give frequency. But the video only shows one 2 dimensional depiction of the string's movement. It is not a complete picture of what the string is doing.

[frankfalbo]

No, from what I understand the rolling shutter is essentially scanning the image top to bottom over time. The string isn't slack enough to be moving to that degree. In order for the string to be going in all those directions at once, it would have to get longer. Strings don't do that, not to that degree. Its not about shutter speed, but the way the rolling shutter captures sections of the string at different times. This is the comment that explains it:

not really, arnar doesn't seem to understand how rolling shutter works: even with your shutter set at 1/4000, the bottom of the picture will be taken around 1/50th of a second after the top of the picture is taken; what the 1/4000 setting means is that each pixel in the image takes light in for a 1/4000th of a second; but with a rolling shutter that is not the same 1/4000th of a second for all pixels

still, you need to set your shutter really fast, because otherwise motion blur will ruin the effect

I'm happy to be wrong about camera stuff, I'm no expert on that subject, but I don't think I'm wrong about a string being incapable of that level of movement.

[RedHouse]

Nope, definately spaghetti, pehaps linguini, but looks like spaghetti to me.

[Ronsonic]

I'm happy to be wrong about camera stuff, I'm no expert on that subject, but I don't think I'm wrong about a string being incapable of that level of movement.

We know bass strings are too rigid to actually move in the way those appear to. If it did, imagine the high frequency output of the things. Those nodes look to be just a few inches apart. That string would be chiming like Jeff Beck harmonics. Not that there isn't some of that, but not at the level that the video appears to have.

[JGundry]

No, from what I understand the rolling shutter is essentially scanning the image top to bottom over time. The string isn't slack enough to be moving to that degree. In order for the string to be going in all those directions at once, it would have to get longer. Strings don't do that, not to that degree. Its not about shutter speed, but the way the rolling shutter captures sections of the string at different times. This is the comment that explains it:



I'm happy to be wrong about camera stuff, I'm no expert on that subject, but I don't think I'm wrong about a string being incapable of that level of movement.

I know it looks strange but I'm pretty sure the video is an accurate depiction. A stand up bass has a very long scale length. The very nature of the instrument means the string amplitude is pretty high. There is a reason the strings on a stand up bass are so far off the fret board when you get some distance from the nut. The further away you get from the nodal point of the nut, bridge or finger acting as the nut, the more string amplitude you get. This video shows the plucking hand so the highest string amplitude is going to be captured.

There is actually an easy way to test this. If anyone still has a CRT display just get a guitar or a bass in a darkened room and watch the strobe effect of the strings. You will have to hunt for the right notes to get wave to come close to freezing. You can see it in this youtube video. I have done this myself and you can see it with the naked eye. It is not a function of the shutter or an artifact of a CMOS sensors shutter. In case you think that the effect with a CRT display is the same thing you are getting from a CMOS shutter then you would expect the string vibration to change with the string's orientation to the screen, but it won't. At least I'm pretty sure it won't. It has been a while since I had a CRT display and noticed this late at night while recording.

[frankfalbo]

No, John I'd have to respectfully disagree. If the cameraman held the camera 90 degrees sideways the "squiggly" effect would go away. Ronsonic is right, that if the string was doing that you'd be hearing high frequency harmonics alone. That is simply not the way the string vibrates.

Edit: I just watched that youtube video and it substantiates my point. Take a steel rod, or something that you know is straight, and wiggle it along the vertical axis of a CRT. The CRT refreshes from top to bottom. That's why it looks that way. In the video you posted the guy doesn't ever hold the bass horizontally.

[JGundry]

No, John I'd have to respectfully disagree. If the cameraman held the camera 90 degrees sideways the "squiggly" effect would go away. Ronsonic is right, that if the string was doing that you'd be hearing high frequency harmonics alone. That is simply not the way the string vibrates.

Edit: I just watched that youtube video and it substantiates my point. Take a steel rod, or something that you know is straight, and wiggle it along the vertical axis of a CRT. The CRT refreshes from top to bottom. That's why it looks that way. In the video you posted the guy doesn't ever hold the bass horizontally.

Okay I just checked this. They do look different based upon orientation but this is why. When you hold the string horizontal you see primarily the fundamental mode of the vibrating string. When you hold it perpendicular to the screen you are seeing a harmonic standing wave because of the refresh rate of the interlaced screen. The string does more than just the fundamental mode. Without the harmonics the string would sound like a frequency counter. The video is an accurate representation of one vibratory mode of the string.

This link show more. Standing Waves on a String

http://upload.wikimedia.org/wikipedi...on_strings.svg

[defaced]

Anyone read the comments below the video? This video is linked and an explanation offered that makes pretty logical sense. Strings effects | Flickr - Photo Sharing!