Panasonic 11G/12G/13G black levels have seemingly doubled overnight? - AVS Forum
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post #1 of 11217 Old 07-31-2009, 03:14 PM - Thread Starter
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UPDATE, FIX DISCOVERED: Users clktmr and markone have uncovered and fine tuned a fix that will restore sets to their original black levels.  Mironto has put together an amazing guide detailing the process.

 

So I knew this has been a problem with Panasonics in the past, but I was kind of hoping it was going to be gradual and not so drastic if it happened at all on the new models. I currently have less than 400 hours on the set. Last set of readings I took before I noticed the (obvious) difference was on the 21st of July, and they were still showing the expected range of 0.008-0.010fL. I was able to duplicate this measure at least 5 or 6 times and never once recorded anything higher. Then came last night, I turned the TV on and it was like a slap in the face, I thought I had changed a setting somewhere (RGB levels, or jacked up brightness somehow), but everything was the same. I got out my meter and measured a surprising .017-.019fL range. I should emphasize I only got out the meter because the difference was so dramatic. It was not a matter of confirming there was a problem, it was a matter of confirming how bad the problem was. Any ideas what could be causing this? Maybe a power supply problem or something? Kind of got me thinking about HDGuru's unexpected MLL findings in their G10/V10 comparison--2 panels that are known to produce near identical black levels. I'm concerned this may be "by design" so to speak.

50G10 Contrast Ratio @ ~200 hours: 4906:1--Black Level 0.008fL, 40fL Windowed White Peak


50G10 Contrast Ratio @ ~400 hours: 2348:1--Black Level 0.018fL, 40fL Windowed White Peak



Cnet 12G (2009 Models) Test Results: Black Level rose from 0.008fL to 0.023fL by 1500 hours
This represents an ~66% reduction in the Contrast Ratio at identical settings--eg. 5000:1 down to 1700:1

Cnet 13G (2010 Models) Test Results: Black levels rose from 0.007fL to 0.012fL by 2500 hours (G20) and 0.004fL to 0.007fL by 1500 hours (VT25).
Tests are still ongoing. Panasonic's Bill Schindler has confirmed to Cnet those are not final values and that they will rise further.


Panasonic's Official Response to the Issue as of 2/4/10

"Automatic Control of Contrast over Operational Lifetime."

Panasonic Viera plasma HDTVs deliver exceptional picture performance throughout the lifetime of these products. Various elements and material characteristics of all electronic displays change with use over time. In order to achieve the optimal picture performance throughout the life of the set, Panasonic Viera plasma HDTVs incorporate an automatic control which adjusts an internal driving voltage at predetermined intervals of operational hours.

As a result of this automatic voltage adjustment, background brightness will increase from its initial value. After several years of typical use, the internal material characteristics will stabilize and no additional automatic voltage adjustments are required. The Black Level at this stabilized point will yield excellent picture performance.

The newest Viera plasma HDTVs incorporate an improved automatic control which applies the voltage adjustments in smaller increments. This results in a more gradual change in the Black Level over time."


(Courtesy of Cnet and David Katzmaier)

Q&A with Bob Perry courtesy of Cnet and David Katzmaier


Thread Updates

D-Nice, through contacts at Panasonic, has confirmed this rising black level affects all 11G/12G/13G ('08/'09/'10) models at a specific hour count. There is no fix planned and it is apparently an unintentional goof on Panasonic's part. He further suggests this problem is Panasonic exclusive and does not seem to affect other PDP manufacturers (e.g. Pioneer or Samsung). He maintains the final level will represent an ~3x increase over the original value (e.g. 0.008 to 0.024fL), but that April (and later) build dates on 13G's (2010's) have possibly had the increases spread out over a much longer span in smaller increments. *D-Nice is a well known, well reputed Professional Calibrator that has been providing accurate information for several years.*

xrox has discovered patents registered to Panasonic that describe very similar behavior. He theorizes the significance of the change is unintentional and attributed to old software, premature, or overly aggressive voltage changes.

He has also posted a summary of the compiled scientific evidence to serve as a reference, and maintains a Zero BL Research Thread.

Bdmers has translated much of the above techno-jargon and put together a general summary of the how and why this is happening.

Most affected users report that Image Retention and Phosphorescence become significantly worse post-elevation.

THX has expressed some interest in feedback from affected owners with THX Certified models (G10/G15/V10/Z1) at THXDisplays@thx.com

Several news outlets have picked up on the story: Cnet Test Results, Cnet Continuing Test, Cnet 1, Cnet 2, Cnet 3, Gizmodo, Gizmodo 2, Engadget, Slashgear, Home Theater Mag, Yahoo Tech, Highdefdigest, PC World, HDNation Ep34, HDguru, Home Theater Geeks, and The Tech Guy


Additional Observations

*The issue has ballooned past the point where it's necessary or practical to link to individual observations, there are numerous reports of affected users (in addition to the below) buried in the thread.*

Several users suspect they have observed the same change: Battousai, Blaken, Pendragoon, akk5000, iVersatile, Plasmafan09, CraigGB, eurocuroc, cold-fusion, smoof15, martin-per, dmichael, MPDamon, exbagboy, tlivesay, killayaw, curly, rick1000

A few users suspect the S1 is affected as well: Lambo, C Tedesco


Additional Measurements

S2: D-Nice *Pre-April Build, short term test, just represents the point he stopped measuring the panels.

G20: D-Nice *Pre-April Build, short term test, just represents the point he stopped measuring the panels.

G25: Smoof15 *March Build.

V10: Donnymac51 (2000 hour update), schwaggy, jackal2001

G10/G15: slovst, Vistekrebel, Smeg36, Richard, Sakke, gregmp, anthrojohn, Audioitis, meteorwar, erupted, dark662

S1: Yukon Trooper, chad473, johnkollen

X1: LarryInRI

11G: DaMaster, TomHuffman

Bdmers and Batpig have put together a graph and Google doc spreadsheet of all posted measurements.


Potential Fixes

iVersatile reports a panel replacement fixes the issue and restores original levels (though only temporarily). Repair tech was amazed at the difference.

Bucknuts also reports success with a panel replacement restoring levels--likely only temporarily.

There have been conflicting reports of "A-Board" replacements fixing (and not fixing) the problem. The majority suggests this is an unsuccessful fix.

Battousai has had apparent success with an "A-board" and "SS-board" replacement improving levels. Possibly only a temporary fix.


Frequently Asked Questions

"Can this change be calibrated out?"

No, a "Brightness" setting of 0 measures the same MLL. You can see the data here.

"What about the "Black Level" settings of "Light" and "Dark" in the user menu?

This setting has no affect on the MLL of the panel, it just crushes low percent stimuli (shadow detail) to black. The "Light" and "Dark" settings both measure exactly the same on black. I assume the option is intended to increase perceived contrast.

"What model lines are affected?"

There are measured reports for nearly all 2009 models in the measurements section above. The 11G PX/PZ lines from 2008 also seem to be affected. D-Nice's contacts suggested all consumer class 2008, 2009, and 2010 model lines are affected. He has run short term evaluations on the 2010 S2 and G20 and noted ~30-50% inflation. Those values just represent the point he stopped measuring the panels. He maintains the end result will be a 3x increase over the out of box MLL. He has also noted that April (and later) build dates on the 13G's (2010's) have possibly had the increases spread out over a much longer span in smaller increments.

"Why might some suspect their units are NOT affected?

Obviously I can't say with any degree of certainty that every single unit is affected, but I can provide some reasons why it might not be noticeable to everyone. First you have to consider the environment. All these models have relatively poor anti-reflective/light-blocking filters, so any ambient light that hits the screen makes this issue very very difficult to notice. Obviously this describes pretty much everyone, very few people view displays in a totally blacked out room. Taking this one step further, to have a truly accurate recollection and perception of the MLL's, you would have to almost view the panel exclusively in this blacked out room as any washed out daytime or lit use could potentially bias ones impression. Lastly, you have to consider people's performance expectations. Post-elevation, these panels produce MLL's and CR's largely on par with mid-range CCFL LCD's from 2008 (e.g. Samsung A550/650/750/Etc). Most users and reviewers described these makes as having "Strong, Deep Blacks" and "High Contrast Ratio's", so it's understandable why some might not identify this as an issue.

"Whats up with the IR/Phosphorescence? It looks nasty in a lot the pics!"

xrox suggests the most probable explanation is that "pixels that were discharged contain way too much wall charge and therefore cannot be properly activated or deactivated". Whatever the cause, there does seem to be a significant difference pre Vs. post elevation.


Comparisons

*This is my own 65S1 and 50G10. I am using the same meter, camera, and settings for this comparison.*

Below is a direct comparison (same meter, same environment) between an aged G10 and a brand new S1. These screen-caps show 11 readings of a 0% grayscale pattern. Point of interest is the "Y" row, which is a measurement of black in candela/square meter (cd/m^2) units.

65S1 @ < 20 hours of use--Black Level 0.006fL


50G10 @ > 1000 hours of use--Black Level ~0.019fL


Pictures of the above S1 Vs. G10 (same camera, settings, and environment--check the EXIF data):



The user Fahrenheit has been keeping a photo journal of his V10's inflation (update).



The user anthrojohn has posted a before and after pic of his 42G15.



The user L7R has posted some comparison shots of an inflated G10 and low quality LCD.

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post #2 of 11217 Old 08-01-2009, 03:52 PM
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Crazy. I am a layperson who owns a G10: could a menu (standard menu) adjustment compensate for this black level increase if/when it occurs on an individual set?
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post #3 of 11217 Old 08-01-2009, 04:38 PM
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A few questions...

What meter are you using?

Do you do all your measurements in a completely dark room?

Are you taking all measurments outside of the service menu?
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post #4 of 11217 Old 08-01-2009, 10:58 PM - Thread Starter
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Quote:
Originally Posted by blaken134 View Post

Crazy. I am a layperson who owns a G10: could a menu (standard menu) adjustment compensate for this black level increase if/when it occurs on an individual set?

Unfortunately no. I could set the Contrast and Brightness at 0 and still measure 0.018fL.

Quote:
Originally Posted by PlasmaPZ80U View Post

A few questions...

What meter are you using?

Do you do all your measurements in a completely dark room?

Are you taking all measurments outside of the service menu?

It's an i1D. I didn't discover the problem with the meter though. Using the TV several times a day, every day, in a pitch black environment, it's pretty apparent when the MLL's double. The unit is located in a FPJ room with dark gray walls, blinds, and double blackout curtains--this is where I took the measurements. All of these listed readings were taken outside the SM. I am aware of the SM overlay elevating the levels. The WB menu, for instances, spikes black to almost 0.050fL.

*Reason for Edit*
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post #5 of 11217 Old 08-02-2009, 08:26 AM
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Quote:
Originally Posted by Orta View Post

Unfortunately no. I could set the Contrast and Brightness at 0 and still measure 0.018fL.



It's an i1D. I realize .008fL is well below its recommended threshold for accuracy, but like I said, I didn't discover the problem with the meter. Using the TV several times a day, every day, in a pitch black environment, it's pretty apparent when the MLL's double. The unit is located in a FPJ room with dark gray walls, blinds, and double blackout curtains--this is where I took the measurements. All of these listed readings were taken outside the SM. I am aware of the SM overlay elevating the levels. The WB menu, for instances, spikes black to almost 0.050fL.

Perhaps choosing the "average many reads on dark measurements" option could help you get more stable readings for black levels from this point onwards. If you can see the difference by eye, then it's a disappointing reality of (at least some) Panasonic Plasmas.

My PZ80U has a black level of 0.017 ftL (has a 20,000:1 native contrast versus your G10's 40,000:1) when the option mentioned above is selected. When it is not selected the value can fluctuate to a substantial extent. That being said, I don't trust my i1d2 for anything below 20 IRE.
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post #6 of 11217 Old 08-02-2009, 02:11 PM
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I wonder how all of this relates to "infinite black." With infinite black, isn't the idea that a pixel shuts down completely if it receives "black" data? Maybe I am confused about this feature (a feature which may be, from what I understand, little more than a marketing scheme).
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post #7 of 11217 Old 08-02-2009, 02:32 PM
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Quote:
Originally Posted by blaken134 View Post

I wonder how all of this relates to "infinite black." With infinite black, isn't the idea that a pixel shuts down completely if it receives "black" data? Maybe I am confused about this feature (a feature which may be, from what I understand, little more than a marketing scheme).

You need to ask Panasonic Marketing about their "infinite black panel" label. That's their baby... and while you are at it, you can ask them about their upcoming "infinte contrast" ratio label
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post #8 of 11217 Old 08-02-2009, 02:36 PM
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Quote:
Originally Posted by blaken134 View Post

I wonder how all of this relates to "infinite black." With infinite black, isn't the idea that a pixel shuts down completely if it receives "black" data? Maybe I am confused about this feature (a feature which may be, from what I understand, little more than a marketing scheme).

That feature is just a panel shut-off when no signal is being received. Unless you plan on watching a completely black screen, it's useless.

http://www.cnet.com.au/entry-level-p...-339294319.htm
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post #9 of 11217 Old 08-02-2009, 03:33 PM - Thread Starter
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Quote:
Originally Posted by PlasmaPZ80U View Post

Perhaps choosing the "average many reads on dark measurements" option could help you get more stable readings for black levels from this point onwards. If you can see the difference by eye, then it's a disappointing reality of (at least some) Panasonic Plasmas.

My PZ80U has a black level of 0.017 ftL (has a 20,000:1 native contrast versus your G10's 40,000:1) when the option mentioned above is selected. When it is not selected the value can fluctuate to a substantial extent. That being said, I don't trust my i1d2 for anything below 20 IRE.

Thanks for the tip PZ. Unfortunately, it hasn't been fluctuating on the readings (beyond 0.002, which is obviously to be expected of the meter). For instance, there was no middle ground where I ever recorded, say, 0.014fL. It literally just doubled. I'm not really sure if this is a hardware problem or expected behavior. My peak luminance and gray scale, for instance, are completely unchanged. It just seems like a really odd thing to go wrong all of a sudden, with so few hours. Anyone have any odd experiences with voltage controllers, power supplies, or something going bad? Clearly I have no idea what goes into the engineering of PDP's, just spit-balling potentials that may or may not even exist.
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post #10 of 11217 Old 08-02-2009, 04:32 PM
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Quote:
Originally Posted by Orta View Post

Thanks for the tip PZ. Unfortunately, it hasn't been fluctuating on the readings (beyond 0.002, which is obviously to be expected of the meter). For instance, there was no middle ground where I ever recorded, say, 0.014fL. It literally just doubled. I'm not really sure if this is a hardware problem or expected behavior. My peak luminance and gray scale, for instance, are completely unchanged. It just seems like a really odd thing to go wrong all of a sudden, with so few hours. Anyone have any odd experiences with voltage controllers, power supplies, or something going bad? Clearly I have no idea what goes into the engineering of PDP's, just spit-balling potentials that may or may not even exist.

I took a look at that older thread describing the rising black levels on some Panasonic plasmas. I too would like to know why this is occuring since it has a huge effect on the contrast ratio of the display.
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post #11 of 11217 Old 08-02-2009, 05:27 PM
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Quote:
Originally Posted by Orta View Post

Thanks for the tip PZ. Unfortunately, it hasn't been fluctuating on the readings (beyond 0.002, which is obviously to be expected of the meter). For instance, there was no middle ground where I ever recorded, say, 0.014fL. It literally just doubled. I'm not really sure if this is a hardware problem or expected behavior. My peak luminance and gray scale, for instance, are completely unchanged. It just seems like a really odd thing to go wrong all of a sudden, with so few hours. Anyone have any odd experiences with voltage controllers, power supplies, or something going bad? Clearly I have no idea what goes into the engineering of PDP's, just spit-balling potentials that may or may not even exist.

i called panasonic earlier today after reading your post, i to noticed this increase about two weeks ago, they had several alternatives for the problem, but one that actually worked for me. It was a complete reboot of the set, why this worked i can only guess, someone with much more knowledge of these sets could probably fill you in better.....to reset the set, power on the tv, hold the menu button on the remote and at the same time hold down the volume minus button on the tv, after about 5 seconds you will see a screen with information come up, at this point hold down the power button on the front of the set until it turns off, then unplug the main power for 30 seconds plug back up and it's like you unboxed it for the first time.

This will reset all the user menu settings back to default, and maybe even the service menu settings(this one i'm not sure about). After finishing the procedure, i poped in a bluray, and checked it out, the letter box bars above and below were noticably darker than what they were moments before. I don't know if this will help, and if it does no clue as to why it worked, but it might be worth the shot..........
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post #12 of 11217 Old 08-02-2009, 06:42 PM
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Quote:
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i called panasonic earlier today after reading your post, i to noticed this increase about two weeks ago, they had several alternatives for the problem, but one that actually worked for me. It was a complete reboot of the set, why this worked i can only guess, someone with much more knowledge of these sets could probably fill you in better.....to reset the set, power on the tv, hold the menu button on the remote and at the same time hold down the volume minus button on the tv, after about 5 seconds you will see a screen with information come up, at this point hold down the power button on the front of the set until it turns off, then unplug the main power for 30 seconds plug back up and it's like you unboxed it for the first time.

This will reset all the user menu settings back to default, and maybe even the service menu settings(this one i'm not sure about). After finishing the procedure, i poped in a bluray, and checked it out, the letter box bars above and below were noticably darker than what they were moments before. I don't know if this will help, and if it does no clue as to why it worked, but it might be worth the shot..........

It does not reset the service menu; I have done this procedure before to reset all my user settings completely. I have no idea why it would affect black level though.
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post #13 of 11217 Old 08-02-2009, 06:59 PM
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Originally Posted by PlasmaPZ80U View Post

It does not reset the service menu; I have done this procedure before to reset all my user settings completely. I have no idea why it would affect black level though.

I think Orta suggested that this rising black level could be "by design." Perhaps it has something to do with the number of hours. Does a "reset" turn back the clock on the "hours used" meter?
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post #14 of 11217 Old 08-02-2009, 07:08 PM
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Quote:
Originally Posted by blaken134 View Post

I think Orta suggested that this rising black level could be "by design." Perhaps it has something to do with the number of hours. Does a "reset" turn back the clock on the "hours used" meter?

I don't think that's what Orta meant. Hours used is like the odometer reading on a car; it cannot be reset. I have done that procedure to reset my user settings more than a few times and it does not reset anything in the service menu, including hours used.
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post #15 of 11217 Old 08-02-2009, 07:18 PM
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Panels change as they age in. Some vendors have a programmed change in the low level activation behavior to account for this in the first few hundred hours of operation. I do not recall if Panasonic was one of them, but in some aging tests I ran a while back it was clear that they do shift black level in the first few hundred hours.

I would not be surprised to find this in any PDP, and would simply calibrate after it occurs.

Yes, calibration is important...every user should be calibrated.

Need electronics repair? A great place to start looking for a shop in your area: http://www.tvrepairpros.com/
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post #16 of 11217 Old 08-03-2009, 03:44 AM
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No, no, no, icaillo, it's not how many angels can sit on the head of a pin, it's 'how many can dance?'(!) Of course the traditional answer to this philosophical question was always 'angels never dance'.

Now, if you would like to start a new thread so we can all discuss the worldly ramifications of this question I'm all for it!
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post #17 of 11217 Old 08-03-2009, 05:57 AM
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Just curious how noticeable this change was to your eye. I see the readings doubled on paper, but did you suddenly notice a brighter picture as well?

Interesting find either way, definately something to keep an eye on.
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post #18 of 11217 Old 08-03-2009, 06:11 AM
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Quote:
Originally Posted by PlasmaPZ80U View Post

It does not reset the service menu; I have done this procedure before to reset all my user settings completely. I have no idea why it would affect black level though.

yeah i agree, i have no idea why this would affect the black level of the set either, but it did. I know some may think this is the placebo affect, but it's not, i could imediatly tell the difference, and still have no idea why this worked.
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post #19 of 11217 Old 08-03-2009, 06:18 AM
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Originally Posted by cleh19 View Post

Just curious how noticeable this change was to your eye. I see the readings doubled on paper, but did you suddenly notice a brighter picture as well?

Interesting find either way, definately something to keep an eye on.

I noticed mine about two weeks ago, and yes it was pretty noticable to me, but i watch a lot of tv, and usually in a very dark room. I don't know if the difference i noticed was as great as Orta measured with his set or not but my eyes were able to disern the difference pretty easily.
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post #20 of 11217 Old 08-03-2009, 06:23 AM
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Quote:
Originally Posted by battousai147 View Post

i called panasonic earlier today after reading your post, i to noticed this increase about two weeks ago, they had several alternatives for the problem, but one that actually worked for me. It was a complete reboot of the set, why this worked i can only guess, someone with much more knowledge of these sets could probably fill you in better.....to reset the set, power on the tv, hold the menu button on the remote and at the same time hold down the volume minus button on the tv, after about 5 seconds you will see a screen with information come up, at this point hold down the power button on the front of the set until it turns off, then unplug the main power for 30 seconds plug back up and it's like you unboxed it for the first time.

This will reset all the user menu settings back to default, and maybe even the service menu settings(this one i'm not sure about). After finishing the procedure, i poped in a bluray, and checked it out, the letter box bars above and below were noticably darker than what they were moments before. I don't know if this will help, and if it does no clue as to why it worked, but it might be worth the shot..........

This sounds like a software bug. Rebooting probably clears out some persistent memory that may be causing this issue. If this is a bug, it may be fixable with a firmware upgrade.

If some experience this while other don't, it may have to do with some particular settings. There's one type of software bug called a memory leak where a piece of data can be too large for it's allocated memory space and the result is if too large a value is stored, it overwrites something adjacent to it and the results are somewhat random and unpredictable.

If the problem occurred after not changing any settings as the initial post claims, then a memory leak is less likely but could still occur as the result of a memory change that has nothing to do with settings. I.e. number of hours in operation.
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post #21 of 11217 Old 08-03-2009, 08:15 AM
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Orta, if you don't mind doing this user reset procedure, could you let us know if you get a measurable difference in doing so?
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post #22 of 11217 Old 08-03-2009, 09:13 AM - Thread Starter
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Originally Posted by battousai147 View Post

i called panasonic earlier today after reading your post, i to noticed this increase about two weeks ago, they had several alternatives for the problem, but one that actually worked for me. It was a complete reboot of the set, why this worked i can only guess, someone with much more knowledge of these sets could probably fill you in better.....to reset the set, power on the tv, hold the menu button on the remote and at the same time hold down the volume minus button on the tv, after about 5 seconds you will see a screen with information come up, at this point hold down the power button on the front of the set until it turns off, then unplug the main power for 30 seconds plug back up and it's like you unboxed it for the first time.

This will reset all the user menu settings back to default, and maybe even the service menu settings(this one i'm not sure about). After finishing the procedure, i poped in a bluray, and checked it out, the letter box bars above and below were noticably darker than what they were moments before. I don't know if this will help, and if it does no clue as to why it worked, but it might be worth the shot..........

Thanks bat, useful bit of info to have. I had tried doing this kind of reset myself, but could only find the "Store Mode" reset that's in the manual. Sadly, this didn't seem to do anything for my problem. Black levels weren't affected at all. Do you remember any of the other potential solutions they had you trying?

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Originally Posted by cleh19 View Post

Just curious how noticeable this change was to your eye. I see the readings doubled on paper, but did you suddenly notice a brighter picture as well?

Interesting find either way, definately something to keep an eye on.

Yea, like bat said, in a dark room it was immediately obvious. I only consulted "the paper specs" because it was so noticeable by eye. If (probably like most people) you use the TV in a room with windows and other ambient light, I don't think you'd ever notice it.
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post #23 of 11217 Old 08-03-2009, 09:26 AM
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sorry to be poking my nose in this thread as some of this is over my head, but is this an issue with only the G10?

also, so "rising blacks" mean the blacks are getting lighter (ie. greyer)?
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post #24 of 11217 Old 08-03-2009, 09:39 AM - Thread Starter
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Originally Posted by Arc3 View Post

sorry to be poking my nose in this thread as some of this is over my head, but is this an issue with only the G10?

also, so "rising blacks" mean the blacks are getting lighter (ie. greyer)?

No idea if it only affects the G10, but if it's something "programmed to happen" as the panel ages like lcaillo suggest (thanks for the input Ic), I would guess it could potentially affect all the Panasonic NeoPDP's (S1/G10/G15/V10, maybe the Z). Pure conjecture on my part, I don't even know if this is what's happening. For all I know I just got a dud unit, something went bad, or it could be programmed behavior. Also yes, rising blacks means getting lighter/grayer. I will admit it seems very odd the unit functions perfectly normal aside from the MLL's. If I were placing a bet right now, I would probably put my money on programmed behavior.
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post #25 of 11217 Old 08-03-2009, 09:39 AM
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What's the current model....G12?

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post #26 of 11217 Old 08-03-2009, 09:50 AM
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Originally Posted by Orta View Post

No idea if it only affects the G10, but if it's something "programmed to happen" as the panel ages like lcaillo suggest (thanks for the input Ic), I would guess it probably affects (at the very least) all the Panasonic NeoPDP's. Pure conjecture on my part, I don't even know if this is what's happening. For all I know I just got a dud unit, something went bad, or it could be programmed behavior. Also yes, rising blacks means getting lighter/grayer. I will admit it seems very odd the unit functions perfectly normal aside from the MLL's. If I were placing a bet right now, I would probably put my money on programmed behavior.

Thanks for the explanation.

The reason I asked is because this is probably what I saw in the store (not bb). When I was just starting out my search for my first hdtv not long ago, the guy showed me the G10 as being a great buy at the price they had it at. What ever was playing on it had the bars at the top and bottom (along with the other dozen or so displays on the wall), and the G10's bars were noticably grey to me. All the other displays were black, or blacker. It really jumped out at me and I asked him, he shrugged his shoulders and left.

I'm not bashing the G10, or saying this is the same thing as your describing, but after seeing it on a showroom, it definitely left a burn-in on my brain
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post #27 of 11217 Old 08-03-2009, 09:52 AM
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"Self-check indication and forced to factory shipment setting:
Produce TV reception screen, and while pressing [VOLUME ( - )] button on the main unit, press [MENU] button on the remote
control for more than 3 seconds.

Exit
Disconnect the AC cord from wall outlet."

This is only found in the service manual, not the user one. (You can hold the power button on the TV instead of unplugging the set if you want; it does the same thing.)
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post #28 of 11217 Old 08-03-2009, 10:00 AM - Thread Starter
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Originally Posted by Arc3 View Post

Thanks for the explanation.

The reason I asked is because this is probably what I saw in the store (not bb). When I was just starting out my search for my first hdtv not long ago, the guy showed me the G10 as being a great buy at the price they had it at. What ever was playing on it had the bars at the top and bottom (along with the other dozen or so displays on the wall), and the G10's bars were noticably grey to me. All the other displays were black, or blacker. It really jumped out at me and I asked him, he shrugged his shoulders and left.

I'm not bashing the G10, or saying this is the same thing as your describing, but after seeing it on a showroom, it definitely left a burn-in on my brain

They could very well have been elevated, but I think what you were seeing was due to the AR (screen) coating Panasonic uses. Any ambient light will wash out the blacks/contrast substantially. You would have to view the displays in a pitch dark room to get an idea of their true black levels. In general, LCD's hold their blacks/contrast a lot better under lighting, as do the higher end Samsung plasmas.
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post #29 of 11217 Old 08-03-2009, 10:12 AM
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Quote:
Originally Posted by Orta View Post

They could very well have been elevated, but I think what you were seeing was due to the AR (screen) coating Panasonic uses. Any ambient light will wash out the blacks/contrast substantially. You would have to view the displays in a pitch dark room to get an idea of their true black levels. In general, LCD's hold their blacks/contrast a lot better under lighting, as do the higher end Samsung plasmas.

I agree, the only place in BB that is ideal for evaluating picture quality and especially black levels is the "Magnolia Home Theater" room, where the larger, higher end models usually sit in a dimly lit room.
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post #30 of 11217 Old 08-03-2009, 10:45 AM
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gotcha. this room did have ambient lighting so that could of very well been the issue as well, thanks for the info!
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