Hitachi 57S700 - Blue leak/outline in scenes with white on black

Discussion in 'Displays' started by JohnKings, Jan 4, 2004.

  1. JohnKings

    JohnKings Stunt Coordinator

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    I have a problem with blue leaking in scenes where white items/images don't seem to merge properly in black backgrounds. This is particularly noticable on men's suits with the transition between the dark suit and the white shirt. A good example of a movie where I have seen this issue frequently is Men in Black. In the transition between the main characters suit jackets and their shirts their appears at times a blue line. I have noticed this problem also exists with white text on black backgrounds. I have read that this is a focus issue. I have tried to cure this using both manual and electrostatic focus, but I can't tell when I have properly focused the blue gun. So here are my questions:

    1. Is this a focus issue?
    2. If so, How do you know when you have properly focused and then defocused the blue gun. Some people have suggested not to defocus, but if I do not there will be a rather nasty purple hue.
    3. When defocusing, should I expect to get rid of the hue entirely? I ask this because I have only been able to remove the hue entirely by making the blue line (in convergence) way too thick.
    4. I have read that you should not defocus using the lense you should defocus using electrostatic is this true?

    If anyone can point me to a detailed overview of focusing the blue gun, it would be greatly appreciated.

    Thanks for any information!

    John
     
  2. JohnKings

    JohnKings Stunt Coordinator

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    Anyone?
     
  3. ChrisWiggles

    ChrisWiggles Producer

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    Can't beleive nobody responded.

    Have you tried convergence? It sounds like a convergence problem to me.... Throw up a grid and see if it's not a convergence problem. I'll bet it is.
     
  4. JohnKings

    JohnKings Stunt Coordinator

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    Chris:

    I have convergence as tight as it can be. I have heard this is a prevalent problem and is related to focus. That said, I am suprised more people haven't commented on it. I am guessing many people have the problem and don't even notice it.

    John
     
  5. JoeRiley

    JoeRiley Stunt Coordinator

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    I have the same problem on my Panny 53wx53, although it's not often noticeable.

    The times I notice it most are actually on the tv's labels.. such as "component one, TV".

    I try to set convergence up as best I can, but it never lines up perfectly. It seems the blue/red lines are sometimes too thick to fit behind the "cross hairs".

    It's not a huge problem however, and I rarely see it on TV/DVDs/Games.
     
  6. JohnKings

    JohnKings Stunt Coordinator

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    Anyone else notice this?
     
  7. The Void

    The Void Agent

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    EDIT:

    I did some more reading and adjusting last night and decided I didn't know enough about what I was talking about. List to Gregg, he's the pro, not me [​IMG].

    I tightened the focus of blue last night and I think that is probably the best solution. There are blue outlines, but they are still only visible up close. I'm still amazed how much better the set looks after focusing.
     
  8. Gregg Loewen

    Gregg Loewen Video Standards Instructor, THX Ltd.
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    argh!

    Hi guys

    If you have blue outlines you dont defocus blue, you have to tighten blue.

    Even with tightening blue you may have some blue outlines. If this is the case you either have to live with it or try to defocus the red and green to match the blue. If you do the later option then any and all convergence error will appear to be much more pronounced.

    Regards

    Gregg
     

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