#rolling shutter
When you search for videos online of plucking a string on an instrument such as the guitar, a surprising number of searches lead you to videos such as the following:
This is not how plucked strings look like! This also does not have anything to do with harmonics of the instrument as well.
The reason why you are seeing those shapes on the guitar is due to the rolling shutter effect on your camera.
But if you do want to see how plucked strings look like, the following videos would be your best bet:
Have a great day!
Links:
DIY: Tutorial running you through how you can recreate the effect on a guitar for yourself
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* This note was made in response to a question asking whether the gif is an accurate representation of how guitar strings worked. Thanks for asking!
