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post #1 of 11 Old 06-20-2012, 07:44 AM - Thread Starter
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I have a Sony 52HX909XBR television hooked up through HDMI directly to a Panasonic DMP-BDP310 Blu-ray player. When I play a Pluge pattern from the DVE Blu-ray disk the 4% below black is not visible with the brightness all the way up. I guess there is a setting in either my television or BD player that is truncating the black signal, but I cannot find it on either the television or the BD player settings. I spent about 2 hours so far trying different settings on both, as well as searching the manuals(not that either mention this). Can someone please help me with where this setting would be on either component?
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post #2 of 11 Old 06-20-2012, 12:00 PM
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It's not worth worrying about. You don't WANT to see levels below black anyway, When you have properly adjusted the brightness control, you won't see any information "below black". If you CAN see information below black (on a TV that doesn't clip black at digital 16), you will get blacks that aren't really black so you'll essentially raise the black level of the display. The whole PLUGE thing exists only to make sure your black is set to the darkest level the TV can produce. If you can't see the 4% below black bar, it's really not an issue. For your TV, just lower the Brightness control until the 2% or 4% above black bar is invisible, then raise the Brightness control 1 or 2 steps to make it visible again. For TVs like yours, a better pattern for setting the Brightness control is a digital levels pattern with values from, say 16 - 25 or so. You can then easily find a Brightness control setting that makes 16 black, but causes 17 (or maybe 18) to be JUST BARELY visible in a completely dark room. That would be your best Brightness controls setting.

Patterns like that are less common than the more coarse PLUGE patterns that appear on just about every setup disc. I don't have any disc titles off the top of my head where they have a digital levels pattern like the one I described, I use the one in my video signal generator so haven't needed to look for on on a setup disc. Perhaps someone else will have a suggestion. But for now... make the 2% or 4% above black bar disappear (too dark) then raise the Brightness control 1 click at a time until that step is visible again.

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post #3 of 11 Old 06-20-2012, 12:11 PM - Thread Starter
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"a better pattern for setting the Brightness control is a digital levels pattern with values from, say 16 - 25 or so. You can then easily find a Brightness control setting that makes 16 black, but causes 17 (or maybe 18) to be JUST BARELY visible in a completely dark room. "

Is that something similar to the flashing patterns on the SpectraCal AVCHD disk?
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post #4 of 11 Old 06-20-2012, 02:12 PM
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Quote:
Originally Posted by douglaswr View Post

"a better pattern for setting the Brightness control is a digital levels pattern with values from, say 16 - 25 or so. You can then easily find a Brightness control setting that makes 16 black, but causes 17 (or maybe 18) to be JUST BARELY visible in a completely dark room. "
Is that something similar to the flashing patterns on the SpectraCal AVCHD disk?

The AVSHD709 disc found on this forum has that exact pattern.

http://www.avsforum.com/t/948496/avs-hd-709-blu-ray-mp4-calibration#post_12373254


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post #5 of 11 Old 06-20-2012, 02:14 PM
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Quote:
Originally Posted by Doug Blackburn View Post

It's not worth worrying about. You don't WANT to see levels below black anyway, When you have properly adjusted the brightness control, you won't see any information "below black". If you CAN see information below black (on a TV that doesn't clip black at digital 16), you will get blacks that aren't really black so you'll essentially raise the black level of the display. The whole PLUGE thing exists only to make sure your black is set to the darkest level the TV can produce. If you can't see the 4% below black bar, it's really not an issue. For your TV, just lower the Brightness control until the 2% or 4% above black bar is invisible, then raise the Brightness control 1 or 2 steps to make it visible again. For TVs like yours, a better pattern for setting the Brightness control is a digital levels pattern with values from, say 16 - 25 or so. You can then easily find a Brightness control setting that makes 16 black, but causes 17 (or maybe 18) to be JUST BARELY visible in a completely dark room. That would be your best Brightness controls setting.
Patterns like that are less common than the more coarse PLUGE patterns that appear on just about every setup disc. I don't have any disc titles off the top of my head where they have a digital levels pattern like the one I described, I use the one in my video signal generator so haven't needed to look for on on a setup disc. Perhaps someone else will have a suggestion. But for now... make the 2% or 4% above black bar disappear (too dark) then raise the Brightness control 1 click at a time until that step is visible again.

if he's clipping BTB, odds are he's also clipping WTW... so, he might still want to see if clipping WTW can be avoided by optimizing settings on the source device and display


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post #6 of 11 Old 06-21-2012, 10:10 AM
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That's liable to lead him into something he doesn't really want like RGB 0-255 whcih will just confuse things. Clipping white at 235 isn't visible without test patterns anyway... there is no real image data above 235, all you get is more steps in specular highlights that are already the brightest things in the image. If you want brighter images overall anyway, clipping at 235 makes 100% white the brightest thing in the image. If you set 109% white to be the brightest thing in the image, 100% white is dimmer than it can/should be. Not that big of a deal for panel displays, but something to think about for projectors, especially in 3D mode where every scrap of brightness helps. All the talk about not clipping white at 235... it's a technical thing, not something that is really improving image quality. Specular highlights (reflections off of chrome, water, etc.) are already typically so bright that having some gradation within them really isn't visible. About the only time you'd see levels above 235 is if the entire screen was very bright, say 95%-100% white but some areas were brihter still... you just don't see images like that in movies or TV.

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post #7 of 11 Old 06-21-2012, 10:59 AM - Thread Starter
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Actually I was going to try changing my settings this weekend from the BD and TV to RGB to see if that works. From what I understand YCbCr is capable of showing more than 16-235, but some hardware keeps this limit. Is there some issue with changing to RGB? You mentioned that is not something that I want to do.

Sorry for what are probably pretty basic questions. I keep finding conflicting information about this subject. I've read that all masters for movies are "full range" (0-255), but that this is compressed to 16-235 on Blu-Ray and DVD. I didn't even worry about this until I used the DVE calibration disk. It seemed pretty amendment that I should try to set up my system to read BTB.
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post #8 of 11 Old 06-21-2012, 01:44 PM
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Quote:
Originally Posted by douglaswr View Post

Actually I was going to try changing my settings this weekend from the BD and TV to RGB to see if that works. From what I understand YCbCr is capable of showing more than 16-235, but some hardware keeps this limit. Is there some issue with changing to RGB? You mentioned that is not something that I want to do.
Sorry for what are probably pretty basic questions. I keep finding conflicting information about this subject. I've read that all masters for movies are "full range" (0-255), but that this is compressed to 16-235 on Blu-Ray and DVD. I didn't even worry about this until I used the DVE calibration disk. It seemed pretty amendment that I should try to set up my system to read BTB.

all video content is 16-235, which includes DVD and BD movies and TV shows

the only thing that could be native 0-255 (PC levels) could be video games (such as on a PC), but console video games are meant to run at 16-235, since they are typically paired with TVs (which by default are video devices) and not PC monitors (which use RGB 0-255 by default)

you want the BD player to send YCbCr to the TV (in most cases) and YCbCr is always 16-235, never 0-255

BTB and WTW occurs when using video levels (16-235), though it's possible a setting on your BD player or TV is clipping all BTB and WTW information... like Doug mentions this is not a big deal despite what some might say, but I maintain that if you can avoid clipping BTB and WTW, you should do so anyways as it can make setting black level and white level easier


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post #9 of 11 Old 06-22-2012, 07:47 AM - Thread Starter
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For the White level pattern. Do I want to set the contrast so 235 matches the background and does not flash? The wording on this pattern is a little confusing. It states "Set white-level so 230-234 or higher flash" I assume that like the black level, the white should not be flashing above WTW. It appears that WTW is not being truncated as these flash all the way up to 253. Actually the contrast setting has to be pretty high for all of the bars to not flash.
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post #10 of 11 Old 06-22-2012, 09:35 AM
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I answered this question in another forum. I'm pretty sure it's the display that's clipping. I have the 210 feeding a 50ST50 and the 220 feeding a 70C8470U, all connnected to the display via HDMI. I get full range of values both for back and white as verified by the pluge patterns on AVSHD. the player in question is the next model up from the 210 and I'd be surprised that it clips while the 210 does not. hence I think it's the display.
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post #11 of 11 Old 06-22-2012, 09:42 AM
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Quote:
Originally Posted by douglaswr View Post

For the White level pattern. Do I want to set the contrast so 235 matches the background and does not flash? The wording on this pattern is a little confusing. It states "Set white-level so 230-234 or higher flash" I assume that like the black level, the white should not be flashing above WTW. It appears that WTW is not being truncated as these flash all the way up to 253. Actually the contrast setting has to be pretty high for all of the bars to not flash.

Interesting, so you're clipping BTB but not WTW. You can set contrast as high as you can before clipping and/or discoloration sets in for 230-234 (if the highest value you want to calibrate for is 235).


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