1. Wat?
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    11 Aug '14 04:01
    Or is it frequency/camera speed recording.

    Is it real?

    https://www.facebook.com/photo.php?v=805329629490060&set=vb.591441797545512&type=2&theater

    -m.
  2. Cape Town
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    11 Aug '14 06:37
    Originally posted by mikelom
    Or is it frequency/camera speed recording.

    Is it real?
    The cameras frame rate is synced to that of the vibration of the water nozzle. (24fps and 24Hz)
  3. Subscribersonhouse
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    11 Aug '14 11:30
    Originally posted by twhitehead
    The cameras frame rate is synced to that of the vibration of the water nozzle. (24fps and 24Hz)
    But the effect is real IMHO. I would like to see what it looks like to a normal frame rate camera if indeed they were doing framing manipulation. You can do something like that without the oscillator and speaker by just wiggling a hose, not as consistent maybe but you could sort of duplicate the effects.
  4. Cape Town
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    11 Aug '14 12:041 edit
    Originally posted by sonhouse
    But the effect is real IMHO. I would like to see what it looks like to a normal frame rate camera if indeed they were doing framing manipulation. You can do something like that without the oscillator and speaker by just wiggling a hose, not as consistent maybe but you could sort of duplicate the effects.
    Without a synced frame rate, you will see an oscillating wave - although at 24Hz it might just look like a spray of water. To get the standing wave effect you have to sync the frame rate with the vibrations. By adjusting the two, you can also make the waves appear to go upwards which is something that is impossible to achieve solely via wiggling - this is similar to the effect of wheels appearing to go backwards on a car when filmed at certain frame rates.
    To see the same effect in real life without the use of a camera, you would need a strobe light. If you vibrate the water nozzle at 50 or 60Hz (depending on where you live) under florescent lighting you should see the same effect. If you put your hand through the gaps where there appears to be no water, you would get wet.
  5. Wat?
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    11 Aug '14 13:44
    Originally posted by twhitehead
    Without a synced frame rate, you will see an oscillating wave - although at 24Hz it might just look like a spray of water. To get the standing wave effect you have to sync the frame rate with the vibrations. By adjusting the two, you can also make the waves appear to go upwards which is something that is impossible to achieve solely via wiggling - this is ...[text shortened]... ct. If you put your hand through the gaps where there appears to be no water, you would get wet.
    Can't agree with the wheel aparently reversing in the direction of the car, because that is apparent at many speeds? Agreed?

    One thing I did notice, at 2 mins, or there abouts, when they say 'reverse' at 23Hz, if you look closely the water is coming OFF the floor and back up, which simply is reverse motion video, is it not?

    So the 23hz, IMHO goes out the window. But there is something happening at 25Hz. It is possible the water molecules themselves are confused at that frequency, and do follow a curved frequency of travel?

    -m.
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    11 Aug '14 13:59
    Originally posted by mikelom
    Can't agree with the wheel aparently reversing in the direction of the car, because that is apparent at many speeds? Agreed?

    One thing I did notice, at 2 mins, or there abouts, when they say 'reverse' at 23Hz, if you look closely the water is coming OFF the floor and back up, which simply is reverse motion video, is it not?

    So the 23hz, IMHO goes out t ...[text shortened]... es themselves are confused at that frequency, and do follow a curved frequency of travel?

    -m.
    Remember that this effect cannot be seen by the naked eye only. Only by a video recorder at a fixed frames per second. Also it can be seen with an aid of an oscilloscope at a fixed fps.

    I understand perfectly the wheel analogy. If you record the water with a camera with 48 fps, 72 fps you get the same result. Same if the oscillator is set on 48 or 72 Hz the same phenomena will occur.

    I would like to see the oscillator set at exactly 18 Hz, what would the result be? Twin sprays...?

    Whenever you drift the 24 hz a bit higher or a bit lower, you see the water moving down and up. Like a rotating wheel in a movie.
  7. Cape Town
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    11 Aug '14 14:16
    Originally posted by mikelom
    Can't agree with the wheel aparently reversing in the direction of the car, because that is apparent at many speeds? Agreed?
    As FabianFnas points out, it reoccurs for multiples of the frequency.

    One thing I did notice, at 2 mins, or there abouts, when they say 'reverse' at 23Hz, if you look closely the water is coming OFF the floor and back up, which simply is reverse motion video, is it not?
    Its an optical illusion, the video is not being played in reverse.

    So the 23hz, IMHO goes out the window. But there is something happening at 25Hz. It is possible the water molecules themselves are confused at that frequency, and do follow a curved frequency of travel?
    No, its entirely an optical illusion.
  8. Wat?
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    11 Aug '14 16:18
    Originally posted by twhitehead
    As FabianFnas points out, it reoccurs for multiples of the frequency.

    [b]One thing I did notice, at 2 mins, or there abouts, when they say 'reverse' at 23Hz, if you look closely the water is coming OFF the floor and back up, which simply is reverse motion video, is it not?

    Its an optical illusion, the video is not being played in reverse.

    So ...[text shortened]... requency, and do follow a curved frequency of travel?
    No, its entirely an optical illusion.[/b]
    Water coming up off the floor is an optical illusion? Pls explain how. I am genuinely interested.
  9. Cape Town
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    11 Aug '14 16:25
    Originally posted by mikelom
    Water coming up off the floor is an optical illusion? Pls explain how. I am genuinely interested.
    What you see, is a photo of water on the floor, then a moment later another photo of water just off the floor, then a photo of the water slightly higher off the floor etc. However, the water in each photo, is actually different drops of water, all of which were falling downwards but because they are nearly in sync with the camera, they appear to be one drop of water moving upwards.
  10. Subscribersonhouse
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    11 Aug '14 21:02
    Originally posted by twhitehead
    What you see, is a photo of water on the floor, then a moment later another photo of water just off the floor, then a photo of the water slightly higher off the floor etc. However, the water in each photo, is actually different drops of water, all of which were falling downwards but because they are nearly in sync with the camera, they appear to be one drop of water moving upwards.
    We really need to see this stuff in real time, eyeballing it in person or using a regular 30 frame or 60 frame per second camera.
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