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Thread: Symmetrical mirror

  1. #1
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    Symmetrical mirror

    Do mirrors that show half your face put on the other half like this:
    http://www.gocomics.com/phoebe-and-h...orn/2018/02/01
    actually exist?
    If so, how do they work? And how can I get one?
    When I try googling, all I get are these four things:
    https://en.wikipedia.org/wiki/Mirror_symmetry

  2. #2
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    I think the giveaway is that the story also involves a unicorn.
    I doubt if anyone makes them, since they'd be deeply unsatisfactory. But you could make one out of a conventional flat mirror (for the mirrored half) and a corner reflector (for the "unmirrored" half). Then all it would require would be careful relative positioning of head and mirror halves.

    Grant Hutchison
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  3. #3
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    you could photoshop your face to reflect one side or the other.
    Formerly Frog march.

    Newscaster: ... But I've just had a report that a representative of Disaster Area met with the environmentalists this morning and had them all shot, so now nothing stands in the way of the concert going ahead this afternoon on this beautiful sunny day.

  4. #4
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    Actually, years ago someone told me about these, so I know they are at least an Urban Legend and not something Simpson just dreamed up.

  5. #5
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    Video displays show how you're seen by others instead of showing the mirror image that we're used to seeing. While finding the center of a face and generating a symmetrical image is rather complex, I'd expect one could be designed to show you something appropriate, including alternating which half is mirrored.
    Selden

  6. #6
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    There are any number of mobile phone apps that do this for you, but I think with still photos rather than realtime video.

    Grant Hutchison
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  7. #7
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    You young whippersnappers and your phone apps. If you want to see yourself as others do, you don't need a video display or a phone - just look at yourself in an elevator that has mirrors for walls.

    When you look into the corner of two mirrors perpendicular to each other, you see yourself as others see you.



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    Last edited by DaveC426913; 2018-Feb-01 at 08:10 PM.

  8. #8
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    Yeah. That's the "corner reflector" bit of my post. But you need to apply that effect to the same half of the face as is being directly reflected in a flat mirror, and combine the two reflections along the midline of the reflected face, in order to produce the effect Tom wants. It's possible, but it would be a real faff, since all three components (flat mirror, corner reflector, face) need to be in a unique set of positions relative to each other, or the effect won't work. I can't see why anyone would want to do that.

    Grant Hutchison
    Blog

    Note:
    During life, we all develop attitudes and strategies to make our interactions with others more pleasant and useful. If I mention mine here, those comments can apply only to myself, my experiences and my situation. Such remarks cannot and should not be construed as dismissing, denigrating, devaluing or criticizing any different attitudes and strategies that other people have evolved as a result of their different situation and different experiences.

  9. #9
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    I still don't see how to do it. And I don't see how to get the light
    paths the same length so the two halves will be the same size.
    And will it work for both eyes simultaneously?

    -- Jeff, in Minneapolis
    http://www.FreeMars.org/jeff/

    "I find astronomy very interesting, but I wouldn't if I thought we
    were just going to sit here and look." -- "Van Rijn"

    "The other planets? Well, they just happen to be there, but the
    point of rockets is to explore them!" -- Kai Yeves

  10. #10
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    Quote Originally Posted by Jeff Root View Post
    I still don't see how to do it. And I don't see how to get the light
    paths the same length so the two halves will be the same size.
    And will it work for both eyes simultaneously?
    No, it won't work for both eyes simultaneously. One of the reasons I described it as "deeply unsatisfactory".

    Grant Hutchison
    Blog

    Note:
    During life, we all develop attitudes and strategies to make our interactions with others more pleasant and useful. If I mention mine here, those comments can apply only to myself, my experiences and my situation. Such remarks cannot and should not be construed as dismissing, denigrating, devaluing or criticizing any different attitudes and strategies that other people have evolved as a result of their different situation and different experiences.

  11. #11
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    Quote Originally Posted by grant hutchison View Post
    No, it won't work for both eyes simultaneously. One of the reasons I described it as "deeply unsatisfactory".
    Are we talking about simply reflecting your whole face?
    Or are we still talking about reflecting half the face onto the other side?

  12. #12
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    We are talking about reflecting one half of the face in two images
    that are mirror images of each other. One has to be reflected an
    even number of times and the other has to be reflected an odd
    number of times. I don't see how to do that without the images
    ending up different sizes.

    -- Jeff, in Minneapolis
    http://www.FreeMars.org/jeff/

    "I find astronomy very interesting, but I wouldn't if I thought we
    were just going to sit here and look." -- "Van Rijn"

    "The other planets? Well, they just happen to be there, but the
    point of rockets is to explore them!" -- Kai Yeves

  13. #13
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    Quote Originally Posted by Jeff Root View Post
    We are talking about reflecting one half of the face in two images
    that are mirror images of each other. One has to be reflected an
    even number of times and the other has to be reflected an odd
    number of times. I don't see how to do that without the images
    ending up different sizes.
    Hint: the mirrors can be different distances from the viewer.

    Grant Hutchison
    Blog

    Note:
    During life, we all develop attitudes and strategies to make our interactions with others more pleasant and useful. If I mention mine here, those comments can apply only to myself, my experiences and my situation. Such remarks cannot and should not be construed as dismissing, denigrating, devaluing or criticizing any different attitudes and strategies that other people have evolved as a result of their different situation and different experiences.

  14. #14
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    Come to think of it, the person may have meant this:
    https://en.wikipedia.org/wiki/Non-reversing_mirror
    so perhaps Simpson did make it up.

  15. #15
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    If you put a mirror vertically against your nose, a distant viewer will see your half face plus its reflection, making a symmetrical face. So if you now place a distant mirror where the viewer was, you will see yourself that way. Harry Worth used to stand by a shop window to look like that and raise his leg creating an amusing star jump effect. So a right angle corner mirror will do the trick , but you place one mirror to your mid line so you are now using just one eye. If you double up in a tee square arrangement you get two different symmetrical views and your brain will average them out, maybe.
    sicut vis videre esto
    When we realize that patterns don't exist in the universe, they are a template that we hold to the universe to make sense of it, it all makes a lot more sense.
    Originally Posted by Ken G

  16. #16
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    I get a half-silvered mirror and four regular mirrors. The half-silvered
    mirror and three of the regular mirrors are at 45-degree angles. The
    remaining mirror is straight-on and farthest away. A single reflection
    in the straight-on mirror for half the face, four reflections in the four
    angled mirrors for the other half.

    -- Jeff, in Minneapolis
    Last edited by Jeff Root; 2018-Feb-02 at 04:30 PM.
    http://www.FreeMars.org/jeff/

    "I find astronomy very interesting, but I wouldn't if I thought we
    were just going to sit here and look." -- "Van Rijn"

    "The other planets? Well, they just happen to be there, but the
    point of rockets is to explore them!" -- Kai Yeves

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