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Panasonic 11G/12G/13G black levels have seemingly doubled overnight? - Page 11

post #301 of 10829
10/16/09 at 3:43pm
Jeff,

I know that we know when we don't know and know enough to let others know.

I don't use Calman so I can't give explicit instructions but there must be a way to measure the capability of the Spyder in a totally black environment. Use the 'black box' method that I mentioned a few days ago or the flannel-in-a-box method that I posted today.

Take a reading on the plasma with the set off (as mentioned before) to get a test baseline. From there, I would take continuous readings on the plasma for 0% stimulus. Use different pre-conditions, i.e., a 0% reading right after no input, right after 100% stimulus, right after a wipe, etc. Let you imagination lead. Finally repeat the whole procedure.

Larry
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post #302 of 10829
10/16/09 at 4:16pm
Quote:
Originally Posted by LarryInRI View Post

Jeff,

I know that we know when we don't know and know enough to let others know.

I don't use Calman so I can't give explicit instructions but there must be a way to measure the capability of the Spyder in a totally black environment. Use the 'black box' method that I mentioned a few days ago or the flannel-in-a-box method that I posted today.

Take a reading on the plasma with the set off (as mentioned before) to get a test baseline. From there, I would take continuous readings on the plasma for 0% stimulus. Use different pre-conditions, i.e., a 0% reading right after no input, right after 100% stimulus, right after a wipe, etc. Let you imagination lead. Finally repeat the whole procedure.

Larry

Gotcha. Basically use good scientific techniques and approaches to get at both accuracy and precision. Same way we'd check any other instrument for plus-minus range of error, right?

Since I have my 46G10 with many hours on it, and a brand new 54G10 (mfg date of May) I should have a very good setup for a range of measurements and tests and comparisons.
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post #303 of 10829
10/16/09 at 4:30pm
Quote:
Originally Posted by jefflackey View Post

Gotcha. Basically use good scientific techniques and approaches to get at both accuracy and precision. Same way we'd check any other instrument for plus-minus range of error, right?

Since I have my 46G10 with many hours on it, and a brand new 54G10 (mfg date of May) I should have a very good setup for a range of measurements and tests and comparisons.

Right.

Unfortunately, both my 42 and 50X1s were bought at the same time and have about the same number of hours on them. But my black level on both sets has been between 0.016 and 0.019 ftL so I really can't say that I've seen a significant change.

On the other hand, my first readings were taken with about 200 hours so I don't know what the black level was out of the box. But then again, the X1 does not have the neo panel so it is a different beast than the G10.

Larry
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post #304 of 10829
10/17/09 at 12:03pm
Well, results so far are not promising. While the Spyder3 with it's extra sensors (over, say, the Eye1 LT) has done a very nice job of helping me calibrate overall greyscale and drvs and cuts, I'm not sure it's all that great at extremely low light.

I started by wrapping it in a black shirt and putting it in a black bag. Got 00000 every time.

Next, I went to my brand new 54G10. Measured with the TV off. Again, all I get is 0.0000

OK - next I just turned on the new 54G10 with no signal. Let it warm up, let Spyder3 warm up with it. lightly touched meter when doing reads to make sure it was making full contact. When I did this, my results came in at .0018, .0018, .0011, .0018, 0, .0018, .0142, .0011, .0018, 0.000, 0.0011, 0.0018. If I kept reading, I got this same general pattern - occasional 0.00000, mostly 0.0018, occasional 0.0142.

Next, my 46G10, which I've had since about June. TV off, same results, all 00000. TV on, no signal. Occasional 0.0000. mostly 0.0024. Occasional 0.0178.

So, I don't know what to make of these numbers. I set CalMan to use the Low Light Handling features of the unit, set it to take longer reads (5 or 7 seconds,) etc. I will get, on my 46G10 for example, a string of .0024s (in continuous read mode) - then a couple of 0.0000, then .0024, then I might get a couple of 0.0178.

Ugh
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post #305 of 10829
10/17/09 at 2:07pm
Jeff,

Even without all the detailed data, I think that some conclusions can be drawn.

1) Your Spyder is capable of measuring very low light levels. The consistant 'total black' readings of zero show that.

2) Discarding the extreme high and low readings on your 54G10, it appears that 0.0018 ftL is the right number.

3) Discarding the extreme high and low readings on your 46G10, it appears that 0.0024 ftL is the right number.


If possible with Calman, I suggest increasing the reading time from 5-7 seconds up to maybe 15 or so seconds.


Larry
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post #306 of 10829
10/17/09 at 3:21pm
Quote:
Originally Posted by LarryInRI View Post

Jeff,

Even without all the detailed data, I think that some conclusions can be drawn.

1) Your Spyder is capable of measuring very low light levels. The consistant 'total black' readings of zero show that.

2) Discarding the extreme high and low readings on your 54G10, it appears that 0.0018 ftL is the right number.

3) Discarding the extreme high and low readings on your 46G10, it appears that 0.0024 ftL is the right number.


If possible with Calman, I suggest increasing the reading time from 5-7 seconds up to maybe 15 or so seconds.


Larry

Thanks Randy. It looks like the longest I can select is 10 seconds (I'll check with the CalMan folks and see if there is a way to increase it further, perhaps some kind of ini setting.)

I'm going to spend some time tomorrow and run an extreme set of readings - as in perhaps 50 or more in a row - on both sets with the no-input screen. While there's no way to determine the accuracy of the numbers, that should allow for a good data set for the precision, and thus allow a valid comparison between the two sets. FWIW, the .0024 fL is also the number from my very first calibration of the 46G10.
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post #307 of 10829
10/17/09 at 4:45pm
Quote:
Originally Posted by jefflackey View Post

Thanks Randy. It looks like the longest I can select is 10 seconds (I'll check with the CalMan folks and see if there is a way to increase it further, perhaps some kind of ini setting.)

I'm going to spend some time tomorrow and run an extreme set of readings - as in perhaps 50 or more in a row - on both sets with the no-input screen. While there's no way to determine the accuracy of the numbers, that should allow for a good data set for the precision, and thus allow a valid comparison between the two sets. FWIW, the .0024 fL is also the number from my very first calibration of the 46G10.

Orta's measurements on his 50G10 were 0.011 ftL (0.037 cd/m^2) for his earlier calibration to 0.016 ftL (0.056 cd/m^2) for his latter one. The first measurement was with his brightness control at 64-67 and his latter measurement with the brightness at zero.
http://www.avsforum.com/avs-vb/showt...0#post17256160


Your measurements on the 54 and 46G10 seem to be less than half of his at 0.0018 and 0.0024 ftL. I find that interesting since you both use a Spyder 3.

not Randy
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post #308 of 10829
10/17/09 at 6:24pm
Quote:
Originally Posted by LarryInRI View Post

Orta's measurements on his 50G10 were 0.011 ftL (0.037 cd/m^2) for his earlier calibration to 0.016 ftL (0.056 cd/m^2) for his latter one. The first measurement was with his brightness control at 64-67 and his latter measurement with the brightness at zero.
http://www.avsforum.com/avs-vb/showt...0#post17256160


Your measurements on the 54 and 46G10 seem to be less than half of his at 0.0018 and 0.0024 ftL. I find that interesting since you both use a Spyder 3.

not Randy

Duh, meant to type Larry.

Actually, I think Orta uses an Eye1 LT.

Just as an unscientific observation, I turned the lights all off in the den and in the bedroom. 46G10 in the bedroom, 54G10 in the den. So basically two dark rooms. Both TVs had been running for a couple of hours when I did this.

In a totally dark room, input set to an unused HDMI (so blank screen) I could not see a difference between the two. I don't know what the screen is supposed to look like on an unused input, BTW - but this was a brand new 54G10 and a 5 month old 46G10. Both screens (in completely dark rooms) did look a little "gray" - new and old - which surprised me, since my black levels on good sources on both look (to my eyes) extremely good. But perhaps in totally dark rooms my pupils are large enough that it makes the screens look a little lighter than "off." But I certainly could not see a difference between the new screen and the old screen by eyeball in those conditions.

FWIW.
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post #309 of 10829
10/17/09 at 6:53pm
I think my G10 looks darker when it's receiving an all black signal vs. an unused input screen also. At first you think it's pretty dark, but when you turn the tv off you realize how bright it actually is. But, say a movie fades to all black, I think it looks darker than an unused input which is a very light shade of gray. I wonder if it could be some sort of screen protection implemented by the tv? Supposedly, the black bars can harm the sets in the first couple hundred hours, so I think it would make sense that a "no input" situation would make the tv a lighter shade so as not to harm the set.
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post #310 of 10829
10/17/09 at 7:02pm
Quote:
Originally Posted by jedimasterchad View Post

I think my G10 looks darker when it's receiving an all black signal vs. an unused input screen also. At first you think it's pretty dark, but when you turn the tv off you realize how bright it actually is. But, say a movie fades to all black, I think it looks darker than an unused input which is a very light shade of gray. I wonder if it could be some sort of screen protection implemented by the tv? Supposedly, the black bars can harm the sets in the first couple hundred hours, so I think it would make sense that a "no input" situation would make the tv a lighter shade so as not to harm the set.

Yeah, I'm gonna see if I can get some actual data of some kind. Unused input definitely does not look deep dark black like deep dark black scenes do. Unless my eyes are fooling me.
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post #311 of 10829
10/17/09 at 7:44pm
Jeff,

First of all, with black levels that you are reading and your description that the screens 'did look a little "gray"' make me jealous. With no input, the screens on the X1 in a dark room look quite gray -- glowing. Of course, it is not all that noticeable with content on the screen -- even with a movie OAR wider than 16:9.

This doesn't surprise me since the black level calibration readings are what they are. They show the difference. However, it still does not address the problem that plagues the OP, Orta. BTW Qrta uses a Spyder 3 and the HCFR software.

WRT the 'no input' situation: it probably can be best created with a shorted RCA plug in a composite video input.

Finally, I doubt that, under any condition, Panasonic would use any circuitry to lighten the blacks. That would be counterintuitive.

Larry
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post #312 of 10829
10/17/09 at 10:58pm
Thread Starter 
Quote:
Originally Posted by LarryInRI View Post

Orta's measurements on his 50G10 were 0.011 ftL (0.037 cd/m^2) for his earlier calibration to 0.016 ftL (0.056 cd/m^2) for his latter one. The first measurement was with his brightness control at 64-67 and his latter measurement with the brightness at zero.
http://www.avsforum.com/avs-vb/showt...0#post17256160


Your measurements on the 54 and 46G10 seem to be less than half of his at 0.0018 and 0.0024 ftL. I find that interesting since you both use a Spyder 3.

not Randy

Yep, I use an i1, not a Spyder. Those early readings of .011fL are pretty inflated in their own right because they were actual calibration runs. I had been burning 70-100% gray windows (and color windows) for like half an hour+, and there was a lot of IR/phosphorescence. I also only zeroed the meter once at the start of the run, and those measures were from the tail end. I just posted them cause they were the only chc's I had saved. The 0 brightness .016fL measure was an ideal scenario where I really did nothing but mll, and it only took maybe 5 minutes total. When I did the same for early runs, I never measured anything higher than .008-.009fL, but they didn't seem worth saving at the time.
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post #313 of 10829
10/18/09 at 8:21am
now at this point some people here measured the black levels and some not but all of us can see with the open eye the black levels getting lighter. I am still waiting for panasonic to call me back. Did anyone figure out if the problem can be fixed in the SM or its just the panel itself
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post #314 of 10829
10/18/09 at 8:47am
Quote:
Originally Posted by Orta View Post

Yep, I use an i1, not a Spyder.

Whic i1? D2l/LT or Pro?
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post #315 of 10829
10/18/09 at 8:51am
Quote:
Originally Posted by jedimasterchad View Post

Supposedly, the black bars can harm the sets in the first couple hundred hours, so I think it would make sense that a "no input" situation would make the tv a lighter shade so as not to harm the set.

Little side point here that has nothing to do with whether the Panasonic displays deep black on a disconnected input signal, but an all black screen won't harm a TV, it would actually preserve the TV. The issue with them occurs when there is other content on the screen. That other content wears down the phosphors, while the black areas don't, leading eventually to uneven wear.

Isn't the Panasonic supposed to shutoff the display completely when it sees an all black input signal and hence achieve "infinite black"? Hopefully folks are getting confused by this ... as it's completely artificial.
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post #316 of 10829
10/18/09 at 12:36pm
Thread Starter 
Quote:
Originally Posted by glaufman View Post

Whic i1? D2l/LT or Pro?

i1D, not the pro.
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post #317 of 10829
10/18/09 at 1:29pm
Orta, I'll correct your meter type in my list.


It appears that after all this discussion there exists no consistent set of data taken under the same controlled conditions on the same model TV using the same instruments. There has been no independent tests taken by others under the same conditions to verify any readings.

With respect to the visually observed increase in black levels, that certainly is not considered verifiable proof.

I really don't know how anything can be proved to convince Panasonic that there is a problem given that only some, yes even one professional calibrator on a different generation set, seem to have noted or noticed an increase in black level. Yet another owner, specifically Jeff, has two sets of the same model (different panels though) which have reading that show wonderful blacks on both.

I'm confused.

And all the speculation by those with no technical training that maybe Panasonic may have purposely increased the blacks or that maybe Panasonic has a special circuit to reduce the blacks does nothing to move this highly technical discussion along. (For those of you who believe the marketing BS that Panasonic has a way to reduce black level, explain why a totally blank screen with no input is not 'black'.)

I expect much vehement disagreement with me about these comments and even some name calling but so be it.


Larry
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post #318 of 10829
10/18/09 at 1:39pm
Larry, the bit about the black level control you misunderstand. The "increased black level jargin" clearly is BS, but what I was referring to is the fact that Panasonics have technology built into them that is designed to match black level to the content (i.e. it BRIGHTENS the black level, not reduces it). This I guess is designed to help prevent IR/Burn-in. You can see it very clearly on their sets playing any content with black bars. They'll get lighter or darker depending on the content. So yes, there very well could be a circuit in there that's getting fried or malfunctioning designed to brighten the black level (in this case either via firmware or malfunction, not resetting it to the proper value or glitching out and increasing the value it's supposed to reset to).
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post #319 of 10829
10/18/09 at 1:57pm
Quote:
Originally Posted by dlplover View Post

Larry, the bit about the black level control you misunderstand. The "increased black level jargin" clearly is BS, but what I was referring to is the fact that Panasonics have technology built into them that is designed to match black level to the content (i.e. it BRIGHTENS the black level, not reduces it). This I guess is designed to help prevent IR/Burn-in. You can see it very clearly on their sets playing any content with black bars. They'll get lighter or darker depending on the content. So yes, there very well could be a circuit in there that's getting fried or malfunctioning designed to brighten the black level (in this case either via firmware or malfunction, not resetting it to the proper value or glitching out and increasing the value it's supposed to reset to).

That is caused by a totally different phenomena called floating blacks. It is a technical subject and has been around for decades -- before plasmas. And it has nothing to do with IR ot burn-in.

Larry
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post #320 of 10829
10/18/09 at 2:59pm
Ok, apologies. Point being though, it is something that changes the black level and since (I assume) the phosphors themselves aren't jumping brighter in a completely uniform manner, it implies that if this phenomenon is occurring, that it's either something within the firmware or something within the circuitry.

I don't know how they handle this on a technical level, but my hypothesis here is that the section of firmware (or control chip or whatever) that controls the floating black level is malfunctioning, maybe on just these guys' sets or maybe on more of them. It's hard to know, but it's a much more feasible explanation (in my mind) than a "Panasonic engineered these to jump after 300 hours for marketing purposes" explanation. If we assume that not all sets have this problem, then it probably isn't the firmware causing it, in which case it would be some control chip or associated circuitry connected to the part controlling the floating blacks.

If you have a better or different idea, great. If my hypothesis is wrong, that's also great. This isn't about being personally right, but throwing out ideas that might help lead to what's causing the problem on the sets affected so that their owners can hopefully get them fixed. Remember the ideals of science are not to win an argument, but as a group come up with a correct answer or at least proceed to a nearer approximation of one.
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post #321 of 10829
10/18/09 at 3:11pm
Quote:
Originally Posted by dlplover View Post

Ok, apologies. Point being though, it is something that changes the black level and since (I assume) the phosphors themselves aren't jumping brighter in a completely uniform manner, it implies that if this phenomenon is occurring, that it's either something within the firmware or something within the circuitry.

I don't know how they handle this on a technical level, but my hypothesis here is that the section of firmware (or control chip or whatever) that controls the floating black level is malfunctioning, maybe on just these guys' sets or maybe on more of them. It's hard to know, but it's a much more feasible explanation (in my mind) than a "Panasonic engineered these to jump after 300 hours for marketing purposes" explanation. If we assume that not all sets have this problem, then it probably isn't the firmware causing it, in which case it would be some control chip or associated circuitry connected to the part controlling the floating blacks.

If you have a better or different idea, great. If my hypothesis is wrong, that's also great. This isn't about being personally right, but throwing out ideas that might help lead to what's causing the problem on the sets affected so that their owners can hopefully get them fixed. Remember the ideals of science are not to win an argument, but as a group come up with a correct answer or at least proceed to a nearer approximation of one.

The ideals of science are to propose a hypothesis, show the proof by experimenting, and have that proof verified by one's peers. You proposed a hypothesis. Since I cannot prove a negative, it is up to you to present data that can be reviewed and analyzed by those with the proper technical/scientific background.

Larry
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post #322 of 10829
10/18/09 at 4:22pm
Larry, we're actually in agreement but we're on two different pages. If I had one of these sets and this problem, I would do the measurements on it for you or alternatively find someone to do them. I ended up buying a different set as a result of concern over this issue. I was merely stating that in addition to a possible firmware issue, any circuits associated with the black level control ought to be inspected as well if and when Panasonic accepts that there is indeed a problem on some subset of these TV's. In my experience most companies need you to tell them what you think is wrong for them to check it.

In that regard, I agree that it's very important for some qualified calibrators to test these sets to get consistent data, but once that's done (at this point if) and Panasonic agreed there were a problem it would be a good idea to have some idea for things they could check for in addition to whatever else they might check out normally. The more things they check, the more likely they are to find the solution. And you can't assume that just because you think they would check something out anyway that they necessarily would.
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post #323 of 10829
10/18/09 at 6:01pm
dlplover,

You keep saying that there is a "possible firmware issue." What engineering data do you have to come to this conclusion?

And, by the way, there are a at least few PhD scientists contributing to this thread and Panasonic doesn't give a damn what they have to say. I doubt that they will care about what anyone says since they have the 13G models to get ready for production. But if you call them, let us know how you make out.

Larry
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post #324 of 10829
10/20/09 at 6:33am
you don't need PhD to figure it out. Its pretty obviously since happened to lots of people and only after 300 to 500 hours in my case after 1000+ hr. It can only be engineering related issue, and probably they wont come out with a firmware fix but i am sure the g13 panels will be better
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post #325 of 10829
10/20/09 at 11:43am
Who said that it takes a PhD to figure it out? I didn't.

Larry
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post #326 of 10829
10/20/09 at 1:14pm
Thread Starter 
Quote:
Originally Posted by cristian_ro View Post

you don't need PhD to figure it out. Its pretty obviously since happened to lots of people and only after 300 to 500 hours in my case after 1000+ hr. It can only be engineering related issue, and probably they wont come out with a firmware fix but i am sure the g13 panels will be better

I don't know, there are reports of this problem dating back 3 or 4 model years at this point. If it is intentional, I would hazard a guess it is being done to increase the life span of the panel in some fashion. I think they would have "the change" designed in to manipulate specs and reviews, or less sinisterly, to age the panel as rapidly/efficiently as possible. By that I mean they would be "overdriving" the panel in some capacity at first, but it is not something that would be sustainable over a decent lifespan. That is all pure conjecture on my part though, I have no idea what goes into the workings of a PDP. It's just the best potential reason I can come up with.
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post #327 of 10829
10/20/09 at 1:54pm
The black level on a PDP may rise with usage due to the same phenomenon that causes black screen IR. A change in the wall charge characteristics or the MgO characteristics will cause a change in the discharge delay and discharge probability.

If delay decreases and probability increases without any change in driving waveform the black level will become brighter.

If delay increases and probability decreases without any change in driving waveform the pixels will misfire

Pioneer KURO is unique in that the black level is generated using space discharge rather than surface discharge which may reduce the rising black level effect IMO. D-Nice can clarify.

Note: Pioneer data shows that after 4 weeks of white screen aging the black level rises about 13% in its 2005 models.
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post #328 of 10829
10/20/09 at 5:35pm
IR goes away ....will this black IR go away too? what if i dont use my tv for 2 weeks ...will the blacks settle down? I dont think soo. Last night i pause the tv on CNN HD and i could see the black type how black should be ( it was perferct black ) , now if i run a black pattern my black glow.... no input blacks glow....bluray movies black bars glow...i dont get it. Its a software issue for sure because the panel can reproduce pure blacks but only on some circumstances . Im done with panasonic and plasma.
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post #329 of 10829
10/20/09 at 6:11pm
Adios.
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post #330 of 10829
10/20/09 at 8:25pm
Quote:
Originally Posted by cristian_ro View Post

IR goes away ....will this black IR go away too? what if i dont use my tv for 2 weeks ...will the blacks settle down? I dont think soo. Last night i pause the tv on CNN HD and i could see the black type how black should be ( it was perferct black ) , now if i run a black pattern my black glow.... no input blacks glow....bluray movies black bars glow...i dont get it. Its a software issue for sure because the panel can reproduce pure blacks but only on some circumstances . Im done with panasonic and plasma.

That doesn't make any sense...If your blacks are good in the imaging of the display, why care if the black bars or blank screen black are sub-par? Personally I feel my Panny's imaging still looks really good on HDTV, Blu-ray, and PS3 gaming and the blacks there seem pretty good...I wonder if the displayed imaging blacks are better than the black bar blacks or blank input blacks?
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