RE: SP 4805, I have small white "orbs" on my screen in dark scenes.

Discussion in 'Displays' started by Inspector Hammer!, May 11, 2006.

  1. Inspector Hammer!

    Inspector Hammer! Executive Producer

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    I noticed this the other night, whenever there is a scene with a pure black screen, I can see two very faint white circular shaped spots almost right in the middle of the screen. I know that this is caused by some dust or a small hair getting behind the lens and distorting the light, but my question is, how do I get rid of that?

    I tried blowing into the very tiny opening under the zoom ring but it didn't work, when I look into the lens I can actually see a small hair that is most likely causing this problem, I just need to get it out of the way of the light path inside.

    How do I correct this? I'm extremely hesitant about using compressed air to blow in it because that's too much pressure, plus some liquid tends to squirt out of those cans.

    Thanks for the help. [​IMG]
     
  2. todbnla

    todbnla Screenwriter

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    I often see patterns of something during extended dark scenes with my 4805, I think this is common as I have heard others comment on this too! Not sure about your circles though.
     
  3. Inspector Hammer!

    Inspector Hammer! Executive Producer

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    Yeah, like I said i'm pretty sure that it's caused by the light passing through a piece of dust or a hair, I can see it when I look into the lens.

    Also, when I put a piece of white paper right up to the lens, you can see what appears to be a "star field" of white specs projected on the paper, what i'm seeing on the screen is no doubt these same specs only enlarged and out of focus.
     
  4. BradJudy

    BradJudy Stunt Coordinator

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    If the patterns you are seeing are lighter areas that seem to scroll through the picture, you may have a ground loop on your projector. This can be fixed in the same way that ground loops heard on subwoofers can (ground loop breakers or 'cheater' plugs).
     

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