Projector beam size.

Discussion in 'Projectors, Screens & Video Processors' started by iqofafish, Aug 3, 2012.

  1. iqofafish

    iqofafish
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    Probably a really silly question, but at what point of the image projection from ceiling mounted lens to screen, would an 84" diag image become 84" at throw distance of 3m?

    The reason I ask, is that I have curved wooden beam at the side of the wall and I'm trying to figure out if the projected image would hit it. The beam is about 50cm forward of the proposed positioning of the lens and extends roughly 7" into the proposed width viewing area.

    Hope that makes sense at this late hour.
     
  2. bow79

    bow79
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    projectorcentral have a distance calculator which may help you. if you get a piece of graph paper you can possibly draw a scale representation of the room and the sizes and then work it out from that.
     
  3. Tight Git

    Tight Git
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    Surely at 3m, because it only gets to 84" at the screen, and that's 3m away when the throw distance is 3m.

    Is this a trick question, or have I missed something? :confused:
     
  4. iqofafish

    iqofafish
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    Thanks, that's answered it. :thumbsup:

    No not a trick question, I was just trying to thing about how the beam from the lens changes size and shape during it's projection to the screen. So leaves the lens at lens size and gradually gets bigger the closer it gets to the screen.

    Just wanted to make sure it didn't leave the lens at a large size. Like I said, probably a silly question, but didn't want to fork out a grand on a projector, mount it and then find the image on the wooden beam on it's route to the screen.
     
    Last edited: Aug 3, 2012
  5. Tight Git

    Tight Git
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    No problem, my old maths teacher would have been proud of me! :D

    On second thoughts, probably surprised... :blush:
     

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