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Light Sensitivity

  1. Aug 24, 2010 #1

    Danger

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    This might more properly belong in the Biology section, but I figure that it might involve other factors.
    There's something that I've been observing for decades, but never actually noticed until last week when watching an Extreme Close-Up shot in a movie.
    Can anyone explain why an actor's pupils don't contract under the intensity of shooting lights? I'm seriously photophobic, but have been in 4 movies which involved hours and hours of being lighted. Those suckers are bright, but they didn't bother me. Seemingly, no actor is discomforted by them, other than sometimes the heat.
    Is it simply a matter of spectrum range, or polarization, or what? An acquaintance of mine is a movie lighting grip, but I haven't seen him in a couple of years and doubt that he would know the answer to this anyway.
     
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  3. Aug 25, 2010 #2

    lisab

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    Hmm, good question. My guess: cocaine, amphetamines, hallucinogens, or any combination of them.
     
  4. Aug 25, 2010 #3

    Danger

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    Nice try, but I wasn't even drinking in those days. I've sure never done any of that other stuff.
     
  5. Aug 25, 2010 #4

    Office_Shredder

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    Not that you know of.

    The punch is always spiked
     
  6. Aug 25, 2010 #5

    Danger

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    :rofl:

    :uhh:
     
  7. Aug 26, 2010 #6
    I suppose that as long as you never look directly at them, it won't affect the pupils. Pilots who train to fly at night are told never to look at bright lights directly, in order to keep night vision.
     
  8. Aug 26, 2010 #7

    Danger

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    Interesting theory, Doc. I was a pilot, but VFR only. From a physiological aspect, however, I disagree with that plan. As mentioned in my OP, I'm severely photophobic, to the point where I can't go outside in daylight without wearing my photochromic glasses.
    Once in a while on the road, at night, someone fails to dip his lights when approaching. By what you said about pilot training, I should look away. Physiologically, that is not the right thing to do. Peripheral vision is far more photosensitive than is direct focal vision. To avoid discomfort, I look directly at the headlights. I do, however, make sure to consciously compensate for the natural tendency of someone to steer in the direction in which s/he is looking.
    I had to leave for about an hour just in the middle of writing this, so I might have to edit it once I recheck the thread.
     
  9. Aug 26, 2010 #8
    hmm, maybe an answer in here? are movie lights a point source, or spread out over a large area? an issue of uniformity of lighting?
     
  10. Aug 26, 2010 #9

    Danger

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    That might very well hold the solution, Mr. Soup. I've never been in a Close-Up, let alone an Extreme Close-Up, so I'm not sure how those are dealt with. In my personal experience, the Kliegs have been bounced off of multiple reflective sheets to make the lighting more uniform. Good thought. :approve:
     
    Last edited: Aug 26, 2010
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