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Ghosting on Akai CFT2791

Discussion in 'Displays' started by Stephen_Ri, Apr 25, 2003.

  1. Stephen_Ri

    Stephen_Ri Well-Known Member

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    Hi, my problem is that on my tv characters have a white ghost effect around them, especially to the right, when there is a bright scene. In a darker scene the ghost will take on a clearer shadow or not be visible at all. It seems to be worse using component than s-video. Changing brightness has no effect and scan velocity modulation is off. Any suggestions? I'm beginning to think it may be my component cable, which is a cheap one(6ft $20).
     
  2. Stephen_Ri

    Stephen_Ri Well-Known Member

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    I replaced the component cable with a good one, but it still had the ghost problem. A bright white line folowing right edge of characters and objects on the screen, when the scene is relatively bright. Not straight lines, ones following the shapes of objects on the screen. I used my T2 THX optimizer disc and on the convergence crosshatch pattern there is a faint reddish line to the right of the bars. Bought the TV 4 months ago at Sam's Club, but they have a 3 month return policy. Think they'll let me return it anyway? I have good reasons: 2 hours away; thought at first it was s-video cable; bought component cable; forgot about it; annoyed me 2 months later; spent last month playing with settings, researching online and buying more expensive component cable. Anyone have any suggestions regarding either fixing it or returning it? I really don't want to pay for labor at a service center; it'll probably cost half as much as the TV($350). Any comments at all are welcome.

    Stephen
     
  3. TimG

    TimG Well-Known Member

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    Sounds more like a contrast problem then a brightness problem. Contrast basically controls the white level, while brightness controls the black level. Check and make sure your contrast isn't cranked all the way up.

    TimG
     
  4. Stephen_Ri

    Stephen_Ri Well-Known Member

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    Playing with the contrast has little effect. If I turn it down it makes it milder, but thats because the whole screen is darker; the shadow is still there just as much, only darker. The weird thing is, I've been talking about the component input, but when I use s-video the problem isn't nearly as bad. On the crosshatch pattern the s-video convergence is fine. On s-video I get the shadow some, but turning down the sharpness helps there. I don't really like turning the sharpness down much though, as the picture does get blurry. When component is being displayed, the tv doesn't allow me to adjust sharpness or tint, however, I don't think either of these setting have to do with the shadow. I suppose I could use just s-video, but I really don't want to do that; I didn't spend much on this set-up, but I planned on at least watching through component. Any ideas as to what could be the problem?
     
  5. sean_pecor

    sean_pecor Well-Known Member

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    I've read about several things that may cause ghosting. Off the top of my head, here are some of them:

    1) Convergence. Having convergence slightly off in certain spots may increase the ghosting effect in certain

    2) Low-end circuitry. Those sets not fitting into the ultra high-end category have lower quality circuitry (can't remember the specific electrical component) that make ghosting (or ringing) a problem, to some extent, for most televisions.

    3) Sharpness is too high. Mine is about 25%, maybe less. Others on this forum prefer even lower. In a manner of speaking, the blurriness is an illusion; there is actually less distortion and more richness and color accuracy when sharpness is minimized. This is illustrated nicely by the Avia DVD.

    4) Interference from power cables or other poorly shielded cables. I had a ringing problem that I am 90% sure was solved by re-routing video cables far away from all power cables.

    Have you tuned your TV using something like the Avia DVD? If not, its highly recommended. Once your picture, brightness, hue and saturation are properly tuned it may minimize the ghosting effect.

    Hope this helps.

    Sean.
     
  6. Bill Will

    Bill Will Well-Known Member

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    Stephen, was it like that when you first got it or did you just start to notice it? If you can't live with it I would try Sam's Club & see if they will swap it for you. Also a friend of mine is going to buy this set next week & I lost the paper that had the instructions on how to get into the service menu & turn "off" the Velocity Scan Modulation. By any chance can you give it to me step by step on how to shut it off? Thanks. Also if you have any other tips on the set let me know. When he gets it I will watch for the "Ghost" factor on his set.
     
  7. Stephen_Ri

    Stephen_Ri Well-Known Member

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    Sean, thanks for the info. I think it must be a convergence problem, especially after looking at the crosshatch pattern. My cables are well shielded, and I keep them as far away from power cables as possible. It appears that like you said turning down sharpness helps some, but I can only turn it down on s-video, component doesn't allow me to. I called Sam's and they said I could exchange this set for another one even though its been 5 months. They're even going to give me an extra $30 since the price went down; I may use this money for buying an avia disc like you suggested.

    Bill, I did notice it when I first got it, but I figured the TV was warming up or it was the cheap s-video cable or something. What I'd recommend your friend doing is right away using component and see if he has a problem, as component is where is mostly a problem. Here's how to get to the service menu: when the tv is off, use the remote and push the following: mute, 1, 8, 2, power. There will now be a menu saying adjust, options, g2 adjust and reset. Use the remote's channel and volume to navigate; go to the adjust screen. There will be a bunch of abbreviations listed, and SVM is on the list. Set it to zero. I'm no calibrator, but this is how I read to do it. I'll note that my set was already set to zero on SVM. Another thing your friend might need to do is enable 16:9 squeeze mode from the options menu in the service menu; I had to on my set. Remember, when you exit the service menu by pressing power, your colors will automatically be set to dynamic, so that'll need to be fixed from the normal tv options menu. Hope this helps. This is a great TV, just make sure your friend keeps his receipt, just in case.
     
  8. Stephen_Ri

    Stephen_Ri Well-Known Member

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    Oh, and Bill, the problem is not obvious, it is usually only brought out in brighter scenes. If you have the Attack of the Clones DVD, at the beginning, right before the jedi council scene, there is a view from outside the jedi council, zooming in, on these buildings the problem is very obvious.
     
  9. Bill Will

    Bill Will Well-Known Member

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    So if your set was on "Zero" for the SVM you mean it came with the SVM turned "Off" ? That's hard to believe that it would have left the factory in the turned "Off" position. Was the box sealed when you got it? Also I thought the set came with the "Squeeze Trick" enabled? at least that's what I got from what Akai has posted on their website ? I've never really messed around in the service menus & I know my friend will kill me if I mess the set up, because like you Sam's Club isn't close by & he's not going to want to have to return it. Maybe I should just tell him to get a JVC or Sony because with those it's just a button push on the remote. But if it's easy to enable the "Squeeze Trick" maybe I'll give it a shot. What do you change in the service menu to enable that? If he gets the Akai I will check the Component Video Inputs.
     
  10. Stephen_Ri

    Stephen_Ri Well-Known Member

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    "SVM" in the service menu was turned to 0. I'd asume that SVM does, in fact, stand for Scan Velocity Modulation. Your TV may come with with squeeze mode already enabled. If its not than it is very easy to do in the service menu. Just go to "options", down to "zoom options", and push volume up once. Now It'll say "normal, zoom, 16:9", where before it said just "normal, zoom". Turn the TV off, and thats it. You really can't mess the thing up from the options menu.
     

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