Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Thought experiment; what happens if you alternate an image

  1. Jan 29, 2015 #1
    like a person with a background and just the background really fast, like a strobe effect. If you cycle back and forth fast enough would the person appear like normal or 50% see through?
  2. jcsd
  3. Jan 29, 2015 #2
    With human eyes'lens or digital camera lens ?
  4. Jan 30, 2015 #3
    with a digital lens, but I mean how would the image appear on the actual screen? So you take pic of someone standing in room, then another pic of just the room, then using some editing software you cycle back and forth between pics really fast, say 500 cycles per sec (is that hertz?)... What would the "pic" look like (on the computer)when its cycling back and forth like that? thanks
  5. Jan 30, 2015 #4
    Your eyes are interesting. What you see is actually an interpolated image (your brain "fills in" missing data). If you were to move someone back and fourth very fast they would probably look like a distorted but unmoving blob. A belt sander that vibrates might be a good example.
  6. Jan 30, 2015 #5
    I predict the person would look "see through."
  7. Jan 30, 2015 #6


    User Avatar
    Science Advisor

    I agree with Zooby. I think it would be possible to interpret either image as transparent, but since your brain is used to seeing people infront of background you would see a transparent person infront of a background. The background might look odd depending on the background to the image of the person.

    You could probably mess this up with a careful choice of background image. For example if your background was a house and the person was photographed from much further away from a different angle, "a small transparent person floating in front of a house" might make your "instinctive" vision refer the scene to higher authority.
  8. Jan 30, 2015 #7
    This is what I think also, like a ghost image, Im going to try this on windows movie maker, but not sure if it lets you cycle images like that. But what if instead of a person against a background vs just the background you cycle between; 1) person against 1 background and 2) same person against another background. And If 500 cycles s-1 gives you a ghost images, wouldnt the ghost image become increasingly clearer as cycles go to infinity? So that you would be left with one person appearing as if in 2 places at the same time? Im trying to relate this to the idea of a particle being in two place at same time, which i find confusing.
    If you start with a particle moving so fast that it appears to have multiple locations, then what if you were able to gradually slow time down, to the point where the particle starts looking like a ghost image, and then slowed down further where it is only seen at one location. Is a particles omniscience just caused by our perception, or is it actually really in two places at same time?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook