Black Bars Lightened on 1:85:1 Screen?

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post #1 of 4

8/3/12 at 11:01am

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39 Posts. Joined 12/2008
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I have a 120" 1:85:1 screen and while everything looks fantastic regardless of aspect ratio, 2:35:1 content doesn't seem to be a strong as content that fills the screen. The black bars get lightened during bright scenes. Is it normal for the black bars to vary in shades of brightness during projection?

Do I simply think it doesn't look as strong because the black bars aren't framing the picture as well as how the picture is framed when it fills the screen, but in reality, the picture is the same?

Projector: Panasonic PT-AE7000U

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post #2 of 4

8/3/12 at 11:14am

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It is not just the black bars that are losing contrast. It is doing the same to the rest of the image. That is why it is recommended that you use dark light absorbing colors/materials around your screen and for your room. The less light that is reflected back to your screen, the better your black levels will be.

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post #3 of 4

8/3/12 at 12:52pm

3,432 Posts. Joined 12/2008
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keep in mind, you are no longer looking at as much image area so the full image is no longer at 1080 resolution and there is less light being output by the projector.
Those black bars are all pixels in the LCD chip in the OFF position. The reason you see them is because LCD does not do a great job of stopping all the light in the pixels off position. Adding a masking system will eliminate the light colored bars and increase your perceive contrast ..
I.E. Black Velvet covered gator board that is temporarily affixed to the top and bottom of the screen by some creative non damaging manner.

One other issue could be incorrect contrast/brightness and over all image calibration..

post #4 of 4

8/10/12 at 1:15pm

2,959 Posts. Joined 4/2007
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What you might also be seeing is the dynamic iris working on your AE7000. As the screen gets brighter the iris opens up and the black bars get lighter, despite them being 'black' their level will be raised to the projector's minimum black level for that iris position. Of course if your room is very light in colour, then this could also be washout as described by the posters above.

Oops, just realised this is AVS and not AVforums, wondered why I had to log in again...nevermind, my comments still stand.