Light overspill query from projector newbie

Discussion in 'Projectors, Screens & Video Processors' started by NJFow, Jul 19, 2018.

  1. NJFow

    NJFow
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    Hi all,
    I'm a newbie, having just bought an Epson EH-TW650 projector. I'm aware this is an entry level projector but it had great reviews as one of the best budget projectors for home use and after my first use of it, I am definitely impressed with the image quality etc.

    However, there is something I wanted to ask about.

    So far I've set it up to project from table top and have tried both square on and projecting at an angle form the side. In each case there is a really noticeable overspill of light around the actual image. To clarify, I mean that while I can see a straight edge to the projected image, be it a video source or gaming source, there is light outside of that.

    The height of the surface being used for the project does mean there it a need to extend the front leg to tilt the projector up at the screen and when moving the projector to an off centre position there is the expected trapezoidal effect on the image. Using keystone correction the image can be squared but the overspill of light stays distorted. I'm attaching some pictures in the hope they better illustrate what I am trying to explain. They're exposed to show the overspill rather than the screen content but you should be able to see the straight edges of the desired image almost to the edges of the available screen width and then the overspill.

    I strongly suspect this is some rookie mistake in setup but I just cant understand the overspill and why the whole area of light hitting the surface isn't the whole projected image, or to put it another way, why the whole image to b projected doesn't fill the full available area of light.

    I'd be grateful for any hints and tips anyone may have!
     

    Attached Files:

  2. Peter Parker

    Peter Parker
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    When you use keystone, it makes the image smaller by not using the pixels at the edges, but there is still some light transmitted from the unused pixels and that is what you are seeing. They are 'projecting black' but the black is still quite bright and that's what you are seeing.

    If you turned off keystone all of the pixels would be used to make the image but overspill onto the wall. The only way to fix it is to have the projector square on to the screen so it fills the screen without using keystone correction.

    If that isn't an option, some black velvet behind the screen would absorb the overspill you're seeing.

    I take it the projector doesn't have a lens shift to move the image onto the screen without having to use keystone?
     
  3. NJFow

    NJFow
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    That's very clear and helpful, thank you Peter Parker.

    I'll try to turn off keystone and do my best to get as square on as I can, I've read a little about lens shift but no, that's not a feature on my projector.
     

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