Geometry Problems? An inexpensive fix.

Discussion in 'Archived Threads 2001-2004' started by Ron-P, Jul 8, 2001.

  1. Ron-P

    Ron-P Producer

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    I had a few "speed bumps" on my new Mits 46" 16:9. About 1/3 up from the bottom and 1/3 down from the top I could see in certain movie scenes the picture distort. Going into the user 64-point convergence grid, I could see that several of the horizontal grid sectors were compressed or shorter than the others. Although minor, it bugged me. So with some help from the guys over at the SPot, I made the following geometry grid template.
    [​IMG]
    I bought a piece of plexy-glass and cut it to fit the screen. I then measured out and drew the entire grid onto the plexy-glass using a fine point black marker.
    I placed my grid over the TV screen and taped it in place. I then sat back, entered the fine green grid in the service menu that actually moves the points and adjusted them to match my grid. After, I re-did the 64-point user convergence. I then saved the new geometry grid pattern as the factory default.
    Total cost was under $13.00. It has really improved my picture. What's amazing is other than the two bad spots, was how many other areas were off just a little. Now she is nearly perfect. I plan to go back and do some more clean up, after 1.5 hours that was about all I could take for the day.
    Peace Out~ [​IMG]
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  2. Chris White

    Chris White Second Unit

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    Good work Ron! The template looks very nice. It is so much easier and more accurate doing convergence when you have a grid overlay.
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  3. Ron-P

    Ron-P Producer

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    Thanks Chris,
     
  4. Keith Mickunas

    Keith Mickunas Cinematographer

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    How did you know what the accurate spacing for the grid is? I'm curious about doing this myself, but my older Mits doesn't have that convergence option. In the hidden menus I've found convergence settings, but they're not clearly labeled. I to have some bumps on the left side similar to what you described. On letterboxed movies I get a blue line under a portion of the image towards the left side. Anybody have some suggestions on what I should look for? The TV is a Mits 50801.
     
  5. Sebastian_M

    Sebastian_M Stunt Coordinator

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    I have tryed to do the 64 point convergence by eye and its frustrating as hell. I'm might end up ordering the overlays from Toshiba. That looks great Ron, nice work, I just might try that before I order them.
    Seb
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  6. Ron-P

    Ron-P Producer

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    Keith,
    I only had two bad spots on the TVs grid that were noticeable to my eye. I placed the blank sheet of plexy-glass on the TV and marked off a few locations of grid points I knew were good and accurate and used those points. I then took the grid off, measured and drew in all the grid points on the template, creating my grid template. I then placed my template back onto the TV and matched the TVs grid points to my template. Worked perfect.
    As for your blue problem I do not know what that might be. Your TV does not have a user 64-point convergence grid? What you should do is head over to the hometheaterspot.com and go to the Mitsubishi section and post a thread on your problem over there.
    Seb,
    That gird I made is not for the user 64-point convergence grid. It is for aligning the actual grid points in the service menu. It won't help for the 64-point convergence as that is for aligning up the red grid and blue grid to the fixed green grid. I went into the service menu and moved the points of the actual green grid. To learn about the fine green grid, go here.
    http://www.hometheaterspot.com/ubb/Forum10/HTML/001134.html
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    [Edited last by Ron-P on July 11, 2001 at 03:16 PM]
     
  7. Carlo Medina

    Carlo Medina Executive Producer

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    Ron,
    I've been reading your posts and you are truly prepping me for the arrival of my new Panny (hopefully in a week or two). I've enjoyed reading your labor-of-love tweak sessions with your new set and look forward to doing some hardcore tweaking of my own.
    Looks like I won't be needing to make a red-push attenuator after all, since Michael_TLV and JohnnyG figured out how to get the push down to about 10% using Panny's service menu options. That's an amount I can live with, especially since my direct-view Sony TV is at 15%.
    Keep us informed about any new tweaks you discover.
    Thanks!
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  8. Ron-P

    Ron-P Producer

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    Thanks Carlo,
    That's great news about the red-push issue.
    Yep! I love to tweak, I find it fun. Some people do not, they just want the plug-n-play model, not that a TV like that exists. For me, tweaking the HT is nearly just as enjoyable as watching a movie in it.
    Any news on the arrival of the new TV?
    Peace Out~ [​IMG]
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