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  1. #11
    markbarendt's Avatar
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    The formula basically says that light spreads out as it moves away from the source. The rays move in straight lines.

    The closer you get to the source, the more light rays you block. (Your shadow gets bigger)
    Mark Barendt, Beaverton, OR

    "We do not see things the way they are. We see things the way we are." Anaïs Nin

  2. #12
    Dave Swinnard's Avatar
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    Ralph, for another similar, but opposite issue, check Olbers' Paradox...

  3. #13
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    As mentioned above, the inverse square law is designed to explain how the level drops as you move away from the source. However, another factor not often mentioned is that a point source is not considered a point source until you are 1/2 the length of the source, distant from the source.

    So, if you have a flash tube 2 inches long, it does not become a point source until you are 1 inch away. Closer than 1 inch it becomes a line source. With its own set of rules.

    Gotta love electromagnetic radiation. It paid my bills for a lot of years.


    Sent from my iPad using Tapatalk HD

  4. #14
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    I think Zeno said it was pretty bright when he got there.

  5. #15

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    Look at it the other way around, not at how much more bright the light is the closer you get but how much darker the light gets the further away you go.

    So standing at 0 from a point light source you are losing 1/0 (aka not even a number) and that means that the light is as bright as the energy it outputs. Move back and stand 2 away and now you are losing 1/2^2 (aka one-quarter) of the original brightness. Stand 4 away and your light is now 1/4^4 (aka one-sixteenth) lost. Etc.

  6. #16
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    The law of inverse squares states that at least once, any nerd in high school will be put upside down in a trash can by a football player.
    I do use a digital device in my photographic pursuits when necessary.
    When someone rags on me for using film, I use a middle digit, upraised.

  7. #17
    jcc
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    Pretty sure the question was already answered, so I'll just my two cents... Physics loves math, but math could care less about physics.

  8. #18
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    You have to think of it this way Ralph, forget the point light source, forget the distances, no matter how many times you "get closer" you can never actually be at 0 because two things cannot occupy the same space at the same time, and also you will always be 1/4th (or whatever the opposite of quadruple) away from the light source ALWAYS, you will never hit 0 and will never reach the light... It's impossible.
    ~Stone | "...of course, that's just my opinion. I could be wrong." ~Dennis Miller

  9. #19
    MattKing's Avatar
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    Quote Originally Posted by StoneNYC View Post
    You have to think of it this way Ralph, forget the point light source, forget the distances, no matter how many times you "get closer" you can never actually be at 0 because two things cannot occupy the same space at the same time, and also you will always be 1/4th (or whatever the opposite of quadruple) away from the light source ALWAYS, you will never hit 0 and will never reach the light... It's impossible.
    Stone:

    Take some university physics courses and you will find that what you say here isn't actually true.

    Or for that matter, watch a few Star Trek episodes .
    Matt

    “Photography is a complex and fluid medium, and its many factors are not applied in simple sequence. Rather, the process may be likened to the art of the juggler in keeping many balls in the air at one time!”

    Ansel Adams, from the introduction to The Negative - The New Ansel Adams Photography Series / Book 2

  10. #20
    StoneNYC's Avatar
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    Quote Originally Posted by MattKing View Post
    Stone:

    Take some university physics courses and you will find that what you say here isn't actually true.

    Or for that matter, watch a few Star Trek episodes .
    My dad is a real honest to god physicist... I'll ask him tomorrow...
    ~Stone | "...of course, that's just my opinion. I could be wrong." ~Dennis Miller

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