Swimmy/Shifting image on Tosh 40H80

Discussion in 'Archived Threads 2001-2004' started by Travis Braddy, Mar 27, 2002.

  1. Travis Braddy

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    I'm sorry if this has been addressed before, I tried searching, but since I don't know a technical term for this, it was difficult.
    When watching slower paced movies, dramas and the like, where there's a steady focus on someone's face, the image kinda swims around a bit, or like I had layed a sheet of water over the screen. The best example I have is two scenes in Unbreakable, the first is right after Bruce gets rejected on the train, the other is the whole weight-lifting scene. Certain portions of his face seems to stay still, like it should, other parts kinda sway around (almost like it was stretching his face around... weird effect), or swim if you will, ever so slightly. It's very visible and annoying, to me at least. I've tried two different dvd players, both yielded the same results.
    I promise, I'm not on any drugs [​IMG] , but it's quite strange and it really keeps me from enjoying the show.
    Any help on the matter would be most appreciated.
     
  2. HuynH

    HuynH Extra

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    Hi Travis,

    It sounds like you need a bit of congergance. 56 points prefered. Do you know how to do this?
     
  3. Travis Braddy

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    Oh wow, convergence does that? I thought it just accounted for color, not the actual image.

    I might fumble my way through it, but I'm afraid I would horribly screw things up. I really need to get an ISF tech in here, I'm just lacking in funds.
     
  4. Bill Slack

    Bill Slack Supporting Actor

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    Is it on still shots, are is the camera moving (even a bit)?
    If the camera is moving, I agree, you'l need to fix it in the convergence menu; but the problem is actually geometry. So, even if they all line up correctly, that doesn't mean the geometry is correct. You set do geometry by adjusting the green grid and then convering blue/red to the green (don't align green to the other ones!)
    If the problem occurs on still shots, then well, I don't know. Your set is possesed... [​IMG]
     
  5. Travis Braddy

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    Thanks for all the info. It is on moving shots, but it's mainly where the focused object is generally still (like Bruce putting his head against the window, the train shakes and wobbles, but parts of his face don't really move with the rest of the image). I also just ran Aria, and my image is all kinds of messed up, the test patterns were shifted to the left quite dramatically.

    Someone had to be tapdancing on my tv or something, I ran it a few months back and everything seems pretty okay. Strange.

    Anyways, this all really does sound like a job for ISFMan, so I'll try and sell some stuff to get the $500.
     
  6. Bill Slack

    Bill Slack Supporting Actor

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    Yes, defiantley geometry. Don't notice it at all on long shots. I messed up my HD input because the out of box geometry was off. Hard to tell when it's right because I can't generate a test pattern!
    A lot of ISF goes don't do geometry or charge extra for it.
    I've done it myself by spending the $200 on the convergence/geometry grids (you can also make them yourself and save a bunch of money, but that means a bit of work). If you lived around here, I'd let you borrow them; I have the 40X81.
    To get them to stick to the screen I use some easy to remove double stick tape (at least easy to remove from the lenticular screen)
    If it happened without you making any adjustments (if you moved green in the convergence menu, that would be the cause), then perhaps you have a bad convergence board. To get the swiminess to go away green has to be quite precise.
    You can find info about the grids here: http://www.keohi.com/keohihdtv/
    (FYI, there are seperate grids for each TW mode, Full, and HD [which the grids labels 1125i, the japanese hd standard])
     
  7. JohnnyG

    JohnnyG Screenwriter

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    Is this on DVD, or digital satellite/cable? It really sounds like MPEG artifacts to me. MPEG doesn't move portions of the image that don't have sufficient motion. This can lead to exactly what it sounds like you're describing.

    I don't think I've really noticed this on DVD though. Just too-highly compressed digital satellite and cable.
     

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