PetaPixel

Strange Effect When Shooting Bass Player with a Canon 5D Mark II

urbanscreen discovered this strange string-wobble effect when shooting a bass player with a Canon 5D Mark II. No special effects or slow motion were added to the footage — what you see results from the frequency of the strings and the fast shutter speed of the camera. Here’s another video showing the same effect from different angles.

Can anyone explain what’s going on here?


 
  • Evan Tallas

    You’ll notice the speed and the extent of the wobble change as he moves the bass forwards and backwards. It’s pretty much the same effect that you get from holding a pencil by the eraser and shaking it up and down to make the pencil look like it’s bending, except the bass in the pencil in the equation. The high frame rate is actually catching the strings in different physical positions and but they’re also moving with the bass(Pencil).

  • Anonymous

    Mmmm. Nice.

  • http://twitter.com/adamjuneau Adam Juneau

    its the jello effect or rolling shutter; bcoz each frame isn’t taken in the very same time. also happened on the drumsticks when it played, it looks like a boomerang..

  • http://www.facebook.com/jbrandibas Joe Brandibas

    That is rolling shutter in action. As the string vibrates, the camera sensor is scanning down the perceived image one line at a time, as opposed to grabbing the entire frame at once. The string is vibrating out of phase with the camera sensors scan. There are lots of youtube videos on this effect, the best being airplane propellers.

  • http://twitter.com/Martin_Q_Blank_ Phil Lowe

    Stroboscopic effect of the frame rate combined with the simple harmonic motion of the strings. Those are standing waves in the strings at their respective fundamental frequencies.

    ‘ish

  • Oli

    I’d like to see that on a harp.

  • Lewista

    I guess the frequency at which the strings are vibrating are closely matched to the gps that matched with a very quick shutter speed would give this affect? Similar to a cars wheel looking like it is turning backwards when it reaches a certain speed.

  • http://twitter.com/michiexile michiexile

    This is a version of the phenomenon that gives us wobbly cars when shooting film with DSLRs: the shutter speed captures different parts of the string at different points of its vibration period; and the framerate is close enough to a nice multiple of the string’s vibrating frequency that not all that much changes in the string image from one frame to the next.

    Result? Wobbly strings that look as if they’re almost stationary.

  • Bkmvincent

    Ever play a guitar or bass in front of a computer monitor? The same exact thing happens, except you actually see it in real-life, not playing back on a monitor

  • Arturo

    It’s a result of the strings vibrations and the camera’s frame rate not being in sync, as some have told. Also, it happens because the shutter speed is very high, so every frame paralizes the string in a slightly different position than the previous one. If the shutter speed where lower, the string would look blurred, as we normally see it.

  • http://twitter.com/HappyTinfoilCat Happy Tinfoil Cat

    FANTASTIC I love it! Reminds me of quantum mechanics.
    http://tinyurl.com/quantumnmech

  • http://brunmarde.com dale.

    I believe it’s probably magic.

  • http://twitter.com/redvoid redvoid

    It has to do with the differences between video camera “rotary disc” shutters and DSLR bladed shutters. It affects vertical lines more than horizontal ones which is why it is pronounced on the near vertical bass strings. If this video was shot at 24fps then the effective shutter speed would be 1/48 sec and if it was 30fps, the effective shutter speed would be 1/60 sec. As a musician, I can tell you that bass frequencies run from 20Hz-200Hz aka 1/20 to 1/200 of a second, but if you had to generalize, most bass lines in real music are going to be slightly above and slightly below 60Hz or 1/60 sec. So, 30fps = 1/60 sec shutter = very very close to an average bass note which is also 1/60 sec, on a vertical line with a DSLR shutter, you get a near perfect storm for the jelly effect.

    Adorama has a video that explains this:
    http://www.adorama.com/alc/article/HDSLR-Part-1-Shooting-Video-With-a-DSLR-AdoramaTV

  • http://twitter.com/redvoid redvoid

    also camera panning and the left to right movement of the bass neck, which are both present in this clip, will exaggerate the effect of the string being in a different place from frame to frame.

  • Yaczone

    I think most of this is due to the fluorescent light’s frequency in the room being pretty close to the bass notes or the harmonic frequencies of the strings.

  • Cch

    It is the same effect seen when auto tires seem to be turning backwards, or ceiling fan blades seem to be stopped or spinning slowly.
    the stroboscopic effect of shutter speed combined with speed of vibration or rotation give the effect.

  • http://twitter.com/headfirstonly Chris Harris

    Any camera with a CMOS sensor will do this, as the individual pixels are polled consecutively, rather than simultaneously as they are with a CCD sensor. That’s one of the better examples I’ve seen, but my favourite piece of video weirdness is still this footage of an aircraft propeller: http://www.youtube.com/watch?v=LVwmtwZLG88

  • http://www.bogt.dk Thomas Nielsen

    Harmonics indeed. Those who play and have used a strobe tuner know this precise effect. I must admit, though, that this is one cool example. Very cool indeed.

  • Zebedee

    its because of the little pixies that sing to make the sound are holding the strings in shape whilst the camera takes a frame, and the faries make the lovely shapes. Pass me some more of that will you. Mind the gnomes.

  • http://twitter.com/jr_cline jr cline

    Here is video of the same phenomenon http://vimeo.com/12790747 taken with an iPhone 3G.

  • Bigwilliex

    Yes. The speed of the shutter is synchronized with peaks in the waves – it’s like a propellor spinning backwards and forwards. The camera only captures the instantaneous image, and if it captures several images sequentially that are similar, the standing wave can be seen. If it captures different images sequentially, the waves wouldn’t be visible, but a blurred string might be.

  • Anonymous

    Michael… “discovered” is a bit of a stretch here – this is a 2 year old video – has been discussed for quite a while and occurs in many other cameras (as is mentioned here in many comments). Ok, I’ll admit it – I’m just jealous you brought up a 2 year old video and got people to like it several hundred times as if it was something new! Gives me hope for digging into the planet5D archives for older articles LOL!

  • http://www.petapixel.com Michael Zhang

    Hey Mitch, By “discovered”, we were referring to the person/people (urbanscreen) that shot the footage. :)

  • http://nixonbyname.com Chris Nixon

    I would definitely go with the vibrations on the string closely matching the FPS of the camera. I don’t think this is a rolling shutter effect.

  • http://www.blogcatalog.com/blogs/gatehouse-academy-blog Gatehouse Academy Review

    its because of the little pixies that sing to make the sound are holding the strings in shape whilst the camera takes a frame, and the faries make the lovely shapes. Pass me some more of that will you. Mind the gnomes.

  • http://www.thisisjoe.net YJawhar

    It’s because bass guitars have really low frequency, therefor its strings vibrates slower than other string instruments, combined with about 24 FPS and you can actually the strings vibrating in a sort-of sine-wave form.

  • Fishmatter

    It’s got nothing to do with DSLR rolling shutter, or CMOS vs god know’s what. It’s a simple strobe effect, familiar to anyone whose ever used a Technics turntable or shone a party strobe at a dripping faucet.

  • Coopstrom

    I feel like these comments have explained things pretty well, but can you water it down for me?
    Q is this a peculiarity of what we used to call fuzzy logic? or is it something that’s inherent in digital versus mechanical/chemical photography?

  • Fishmatter

    It’s far simpler. The string is vibrating at a certain frequency. If you were to take a snapshot at some arbitrary point in time you would have a freeze frame of its shape. Of course it’s moving at a certain number of cycles per second, so this means that every cycle it will have essentially the same shape. So if you were to take a picture of a string vibrating at 24 Hz every 1/24th of a second, each picture would look the same because the string will have had time to vibrate out to the opposite end of its cycle and back again. If the string is vibrating at, say 25 Hz but you still take pictures 24 times each second then the shape of the string in each successive photograph will be a tiny bit “later” on in its movement. There’s nothing more to it than that.

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  • http://twitter.com/IEBAcom Anthony Burokas

    I’m amazed at how many people think this is not distorted video caused by the rolling shutter of a vDSLR. (Like @Fishmatter)

    Any string player will tell you that the string vibrates as a whole from the point its touched on the neck down to where it’s anchored at the bottom of the instrument. If you took a flash image, you’d see the string moving in it’s entirety, not with multiple sine-wavelengths along its length, as seen in the video.

    The reason it looks this way is because the CMOS shutter of the camera “scans” slow enough that the string vibrates back and forth several times for each frame of video. I have written about this distortion at length, but this one post is easiest to grasp:
    http://ieba.wordpress.com/2009/09/19/wetnoodles/

    Where a drummer can move his sticks so fast they bend.
    Do the sticks actually bend? No.
    Does the CMOS shutter distort reality? Yes.

    It’s not even a frame rate issue as @Fishmatter postulates.
    If it were, then the string would be in the same spot, or a different spot, in each frame- and so appear to not move, or move slowly back and forth- not at the rate at which it really vibrates. You also see this effect with car wheel spokes that seem to go backward as the car drives forward and is filmed by a camera shutter that captures spokes in a cadence that presents to _us_ the appearance of the spokes moving backward slightly with each frame, when, in reality, they move forward a lot, and just happen to be captured at the right moments to look like they are progressing backward.
    That’s not happening here.

    We see multiple ripples on each string. The strings are bending?
    Did they suddenly get longer to take this longer curved pathway from end to end?
    No.

    CMOS shutters in video cameras distort the images they capture.

  • http://www.facebook.com/jbrandibas Joe Brandibas

    Well said, a much longer explanation than mine up above.

  • Lolicht

    This is a “slit-scan” effect, caused by the way the c-mos scan progressively the image … this effect is very interresting, a variation of it was used to create the famous ending sequence (the jump to Jupiter) … more info here :
    http://www.flong.com/texts/lists/slit_scan/
    The same effect causes plane helix to look like flexible plastic … or try to shoot a fan helix and adjust the shutter speed …
    That don’t work with ccd, as they have a global shutter (if you have a camera and want to know if it’s ccd or cmos, that’s a way to test it!)
    b-t-w it’s a very difficult effect to create in post-prod !
    for artistic application see the work of the great polish video artist in the 90’s : Zbigniew Rybczyński

  • Lolicht

    sorry I forget a reference … the famous ending sequence of what ?
    of “2001” !

  • Raf Conan

    you should see forfiter blues on yutube… its the same as on guitar strings… strange

  • http://www.AppraiserNow.com Appraiser Now

    As the string vibrates, the camera sensor is scanning down the perceived image one line at a time, as opposed to grabbing the entire frame at once. The string is vibrating out of phase with the camera sensors scan.

  • Anonymous

    Get a Nikon

  • http://ebridge-interactive.net/ Ebridge Interactive

    The camera only captures the instantaneous image, and if it captures several images sequentially that are similar

  • http://ebridge-interactive.net/ Ebridge Interactive

    The camera only captures the instantaneous image, and if it captures several images sequentially that are similar

  • Manwhoownsaford

    I wouldn’t!  I think it would cause me to barf!  :/

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  • Tamara Temple

    *grumble* this won’t play for me….

  • Mike Salovich

    From this video, I learned about the rolling shutter effect and actually made a whole music video recording a baritone 12-string with similar affect.  It is on YouTube at…   http://youtu.be/wdggA-Qc7f4

  • Gath Gealaich

    It’s called “aliasing”.