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Panasonic 11G/12G/13G black levels have seemingly doubled overnight? - Page 41

post #1201 of 11163
Quote:
Originally Posted by Slickman View Post

Why does everyone recommend the Panny's if it's garbage like people in this thread are saying

not that many people have said it's garbage. it's a great tv. it has a problem and we're trying to solve it.
post #1202 of 11163
Quote:
Originally Posted by pukemon View Post

not that many people have said it's garbage. it's a great tv. it has a problem and we're trying to solve it.

Not all that great if you're the one having this problem, at that point you're probably wishing you bought a cheap Dynex for $300.
post #1203 of 11163
Quote:
Originally Posted by ChosenGSR View Post

Not all that great if you're the one having this problem, at that point you're probably wishing you bought a cheap Dynex for $300.

have you called panasonic and told them about it yet?
post #1204 of 11163
Quote:
Originally Posted by pukemon View Post

have you called panasonic and told them about it yet?

I don't actually own one, I am just really upset as I almost pulled a trigger on one.
post #1205 of 11163
Quote:
Originally Posted by mmoh00 View Post

Why do you say it doesn't bring back the good black? I am aware D-Nice has said that once the black level gets worse, you can't bring it back. Are you just going by his statement or some other knowledge? Just curious.

On more general note, isn't it true that the "initializing voltage" is raised by FW for a particular performance reason and the black problem is just an unintended byproduct? If we somehow fool the FW not to raise this voltage at all, wouldn't it cause other performance problems later on?

At the minimum, I think some people will make use of this clock-reset method if they decide to sell their tvs on craigslist.

Yeah, you could sell your TV as "brand new".

You are right about the voltagemodifications by reason but when they kick in too early and too aggressive, it's better to leave them at the original level IMO.

Should you run into pixelartifacts or something after 2000 or 2500 hours of use, you can still advance the internal clock again to 200 hours or so and let the TV run into it's first voltageadjustment.

About getting the black back after the "bug" kicked in: Of course it is possible to get the voltages to where they were before! It's a letter in the EEPROM, that changes in the exact moment, the internal clock runs over one of the three presetted marks.

I just not have found the hexadecimal letter yet, where the mark is coded. But I'm on it.
post #1206 of 11163
Quote:
Originally Posted by Turrican4D View Post

Now I still haven't found the way to bring the blacks back to where they started, but I provide you with the info you need to prevent your S1, S10, GW10, G10, G15 and V10 to ever be plagued with the black level bug - that's for the G12 Plasmas that haven't reached the magical border yet.

One warning: The following procedure has been tested with several german GW10 and S10 so far! The specific way could be different to US-Models, but since the EEPROM of all G12-models is very close to one another, I doubt it.

Okay, we have to go into the servicemenu. Once you are there, got to the page with the SRV-Tool. Click "Ok" and the SRV-Tool will open.

Since you are users of this thread, you will probably know this SRV-Tool already.

If you went with the cursor down, mark the last field on the right hand and press the Mute-Button for more then five seconds, your amount of hours, that the display was used will be displayed along with the number of times, you powered it on.

Okay, what we do now ist to mark the first field from above on the right hand instead. Again hold down the Mute-Button for more then 5 seconds. An option called "Memory Editor" appears.

You click "Ok" aka the actionbutton at your remotecontrol and voila, here is the heart of your TV, the EEPROM.

"EEPROM Peaks" is our next station. Mark it with the cursor and press "OK". You can navigate with the cursorbuttons of your remotecontrol and move with the channelcontrol up and down through the bunch of pages.

The lines of interest, which contain the internal clock are 6C8 and 6D0!

They can look like the following for example:

6C8: FF FF FF 52 00 00 1E 29
6D0: 02 00 00 00 FF FF 00 00

The fourth hexadecimal letter of line 6C8 represents the number of times, your TV were powered on. 52 means 82 times!

The seventh letter of line 6C8 are the minutes and the last letter same line represents the hours the display has been in use. 1E is 30 Minutes and 29 is 41 hours.

The first letter of line 6D0 makes the hours complete. In our case, it says "02", which means, the mark of 255 hours has been exceeded two times.

This means 256 hours * 2 + 41hours + 30 Minutes-> This panel has been used for 553 hours and 30 minutes!

What we do now? We mark all four letters each and reset them with our volumecontrol to zero! Save each entry to the EEPROM with the Action-Button (aka "OK") on your remote control.

After your changes, press "Exit" two times. You are back in the SRV-Tool. Now press the "Exit"-Button for more then 10 seconds and your TV will restart.

You now have a TV, that has been powered on only one time and has zero hours of use on its shoulders.

Repeat this regulary and the Black level Bug will never touch you.

Another possibility is to set the clock of a new G12 plasma to let's say four thousand hours, since the three voltagebumpmarks should never kick in. This would spear you the need to reset the clock again and again.

i have a px80u and the EEPROM doesnt match with yours i had only ones and zero at that value Can anyone find the values for the px80u?
my hr are: time: 03637:20 count: 0001085 can someone find the right code for those times
post #1207 of 11163
Okay, than the scheme only alignes to the Full HD-Panels.

How many hours has your PX80U on its shoulders? How many minutes an how many times it has been turned on?

Once you know these numbers, you have to translate them into hexadecimal numbers and search for the entries in the EEPROM Peaks.


EDIT: Ok, then you have to look for an E0 (14 * 256), a 35 (aka 53 decimal) = 3637 hours; a 14 (for the 20 Minutes) a 04 and a 3E (4 * 256 + 62 = 1086 turn on times).

The two lines should look like this->

FF FF FF 3E 04 00 14 35
E0 00 00 00 FF FF 00 00

post #1208 of 11163
As I try to put together what D-Nice has said about this, and what others have pulled together as far as info on the voltage increase profile...

It sounds like it's not a problem of premature voltage increases, but rather that the voltages or the control system is inorrect. Therefore, messing with clock settings won't do anything to help. Changing the clock to lower the voltage when the panel is already aged may create other problems. (there's a reason the voltage must be changed... Just not in the way the faulty firmware does)
post #1209 of 11163
As I said: Resetting the clock alone will not reset the entry in the EEPROM, that is responsible for the voltageincrease.

But you could prevent it from happening iif it did not happen already. If you encounter pixel artefacts after 2000 hours or something, then you can take action to alter the voltagelevel afterwards.
post #1210 of 11163
Quote:
Originally Posted by Bdemers View Post

(there's a reason the voltage must be changed... Just not in the way the faulty firmware does)

According to the info in the patent:

Simple version: The more the pixels are used the more difficult it becomes to discharge the gas (requires more volts). If the voltage is not adjusted the gas will not discharge and the pixel will start to misfire.

Detailed version

Initialize - Small discharge in all pixels that resets all pixels in the array to an equal state. It creates wall charge and seed electrons that enable the pixel to be quickly and efficiently addressed.

Address - Each row of pixels is scanned one at a time and pixels are set in the "on" state or "off" state, according to image data, by a very small selective discharge

Sustain - All X and Y electrodes are activated at once and only the pixels in the "on" state will discharge producing light.

The initialization step is the source of the black level as all pixels must undergo this step. As the panel ages the voltage required to create an initialization discharge becomes larger and larger and as such the initialization becomes weaker and weaker (blacks get darker). At some point the initialization discharge starts to fail and then the pixel cannot be addressed or sustained reliably. At this point the panel must increase the voltage in the initialization step which in turn increases the strength of the initialization discharge and in turn increases the black level.
post #1211 of 11163
xrox, thanks again.

Anyone please correct me if i'm wrong with this summary:

- First, let's assume charts from the patent is what's going on on the HW for argument sake. It's copied below for easy reference.

- This whole voltage control scheme is only to improve the black level for the first 1000 or so hours of operation. Nothing else.

- Even if we didn't have any FW bug, black level would have worsened over time somewhat (20%? Notice the contrast ratio drop for the control case plot). (EDIT: Not entirely true. See my comments below) But doubling of black level is NOT normal, not just by going with the chart but also from D-Nice's comments.

- Without the voltage control FW or the FW effectively disabled with EEPROM manupulation, one would need to use the final voltage (235V) from the get-go to avoid cell misfirings later on. Alternatively, one can start with a lower voltage but need to manually raise it as needed. Turrican mentioned this above.

Turrican, your work definitely seem to have merit IMO. Let us know as you find more. Thanks.

EDIT: According to the chart, black level actually improves for the first few hundred hours and then declines back to near the initial level during hrs 600 to 1000. Again, just going with the patent chart only here!
LL
post #1212 of 11163
Turrican,

A quick question: How do you know the voltage is saved to EEPROM instead of being re-computed from the # of hours on every boot up?

EDIT: Oh I see your post above regarding this question. So you deduced that from the observation that resetting the clock doesn't change the voltage?
post #1213 of 11163
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?
post #1214 of 11163
Quote:
Originally Posted by mmoh00 View Post

xrox, thanks again.

Anyone please correct me if i'm wrong with this summary:

- First, let's assume charts from the patent is what's going on on the HW for argument sake. It's copied below for easy reference.

- This whole voltage control scheme is only to improve the black level for the first 1000 or so hours of operation. Nothing else.

- Even if we didn't have any FW bug, black level would have worsened over time somewhat (20%? Notice the contrast ratio drop for the control case plot). But doubling of black level is NOT normal, not just by going with the chart but also from D-Nice's comments.

- Without the voltage control FW or the FW effectively disabled with EEPROM manupulation, one would need to use the final voltage (235V) from the get-go to avoid cell misfirings later on. Alternatively, one can start with a lower voltage but need to manually raise it as needed. Turrican mentioned this above.

Turrican, your work definitely seem to have merit IMO. Let us know as you find more. Thanks.

You have it backwards. Without any voltage control system the black level improves over time because the initialization discharge becomes weaker and weaker. This is why the contrast is going up. The problem is that the initialization becomes so weak that the pixels start to misfire. This is why the voltage is raised to prevent misfiring.

In the control case the black level was high to begin with because the initialization discharge was high to begin with. In the example case the black level is lower (initialization is weaker and it becomes too weak at one point so the voltage is increased)
post #1215 of 11163
So, knowing what we know now about how this works, I cannot believe that Panasonic plasmas are the only plasma displays designed this way.
post #1216 of 11163
Quote:
Originally Posted by xrox View Post

You have it backwards. Without any voltage control system the black level improves over time because the initialization discharge becomes weaker and weaker. This is why the contrast is going up. The problem is that the initialization becomes so weak that the pixels start to misfire. This is why the voltage is raised to prevent misfiring.

In the control case the black level was high to begin with because the initialization discharge was high to begin with. In the example case the black level is lower (initialization is weaker and it becomes too weak at one point so the voltage is increased)

Yes, you are right about black level improving early on (first 600 hrs or so in the chart). I was actually refering to the period after that when the voltage is progressively raised. Between hr 600 to 1000, the black level (and contrast ratio) gets worse by ~20% even with a bug-free control logic, no?

I think we are on the same page except that we were refering to different periods in the control scheme. Again, please correct me if I misunderstood things. Thanks.
post #1217 of 11163
Quote:
Originally Posted by Gov View Post

So, knowing what we know now about how this works, I cannot believe that Panasonic plasmas are the only plasma displays designed this way.

Unkown to me. However, I do know that Pioneer KURO initializes (calls it reset) using space discharge(X-S electrodes) rather than surface discharge (X-Y electrodes). It may be that this method is immune to such problems.
post #1218 of 11163
Quote:
Originally Posted by mmoh00 View Post

Yes, you are right about black level improving early on (first 600 hrs or so in the chart). I was actually refering to the period after that when the voltage is progressively raised. Between hr 600 to 1000, the black level (and contrast ratio) gets worse by ~20% even with a bug-free control logic, no?

Yes I thought you were saying without voltage adjustments the black level gets worse when the opposite is true.

The reason for the voltage control is to prevent misfiring of pixels. Black level/contrast changes are a by-product.

Cheers
post #1219 of 11163
Quote:
Originally Posted by xrox View Post

You have it backwards. Without any voltage control system the black level improves over time because the initialization discharge becomes weaker and weaker. This is why the contrast is going up. The problem is that the initialization becomes so weak that the pixels start to misfire. This is why the voltage is raised to prevent misfiring.

In the control case the black level was high to begin with because the initialization discharge was high to begin with. In the example case the black level is lower (initialization is weaker and it becomes too weak at one point so the voltage is increased)

So, ultimately, the black level will lower itself gradually and it'll be a wash, correct?
post #1220 of 11163
Quote:
Originally Posted by robi1138 View Post

So, ultimately, the black level will lower itself gradually and it'll be a wash, correct?

From the chart the black level changes level off. If the FW bug raises the voltage too much then the rise in black level will be permanent relative to the natural rise in initialization voltage.
post #1221 of 11163
Quote:
Originally Posted by xrox View Post

From the chart the black level changes level off. If the FW bug raises the voltage too much then the rise in black level will be permanent relative to the natural rise in initialization voltage.

So is it confirmed to be a bug or is it that it's easier to notice a sudden change to higher black level than the gradual lowering that was also going on prior to the instantaneous rise?
post #1222 of 11163
Quote:
Originally Posted by robi1138 View Post

So is it confirmed to be a bug or is it that it's easier to notice a sudden change to higher black level than the gradual lowering that was also going on prior to the instantaneous rise?

I can't answer that. D-Nice will know this information. We can only speculate.
post #1223 of 11163
[/quote]

Quote:
Originally Posted by Slickman View Post

That's it!? That super slight difference is what everyone is going crying over?

That pic has been taken in a room with lights on. In pitch black, even V10 is not completely black without anything (bright) on the screen. So that G10 would be dark gray I guess.

That pic is just good example to show there's a difference. To you that's nothing, but contrast ratio between those two sets is huge (if both have same brightness).
post #1224 of 11163
Anyone know if the U1 model (the best buy exclusive model that isn't Neo-PDP) suffers from this problem?

I'm not sure what to do. I had my heart set on a Panny plasma this month, but if the black levels are going to go to hell 1000 hours into the lifespan of the TV, i'm not so sure now. I'm far from a videophile, but the one thing I've always noticed and hated are poor black levels, which was one of the things that attracted me to plasma (for it's good black levels).

Would you guys still recommend one? Is the U1 really much worse even though it isn't Neo-PDP? (I don't care about depth or power consumption if that's the major difference.

Or should I wait for the 2010 round of Panasonic Plasmas?
post #1225 of 11163
I think everyone here needs to realize that this is a specialty forum for people who are willing to post their experiences, both good and bad. The vast majority of tv owners either don't know any better, don't come on internet forums, or are happy enough with their TVs.

It's too easy to get carried away and start thinking that the problems people are having apply to every single person and every single tv.

I almost fell victim to the same thing. After I noticed this thread I started worrying about my 54G10. Worrying about my black levels and if they had gotten worse.

I've had my G10 for over a month now and it's at roughly 500 hours. My black levels seemed to be just fine and the image quality is still amazing.

Just to be sure, I popped the sd card with the break in slides back into the tv and went to a black slide. In all honesty, at night with all the lights off, my tv almost looks like it's not even on. I can definitely tell that it's on, but the screen is so dark that if someone casually walked by, they might not realize that it's actually on. The slides were running in torch mode with the contrast at 100.

I'm keeping my fingers crossed and hoping that nothing goes wrong, but people shouldn't be down on Panasonic because some people unfortunately have had issues.

After a month, I couldn't be happier with my purchase. At the store I preferred the colors of the Samsung 850, but it's buzzing issues, increased input lag, and inferior black levels pushed me towards the G10 and I have absolutely no regrets.

I hope that those who have had issues get them resolved by Panasonic and that the ones without problems stay that way.
post #1226 of 11163
I've been following this thread and thanks to the info provided by Turrican4D was able to figure out the positions of the counter on the EEPROM of brazilian TC-P50G11B (Sort of equivalent to the American G10). My TV had at the moment of the picture 222 hours and 20 minutes, powered on 134 times. (I noticed the black level rise with 200 hours and 10 minutes).

Attachment 162451

First byte of line 580h is number of powerons, 5th byte is minutes e 7th byte is hours.
LL
post #1227 of 11163
This is a photo showing the difference on black levels before and after the rise on my set. Same camera, same ISO, same EV. It may seem subtle but trust me it is not.

Attachment 162452
LL
post #1228 of 11163
Quote:
Originally Posted by Syed117 View Post


I can definitely tell that it's on, but the screen is so dark that if someone casually walked by, they might not realize that it's actually on. The slides were running in torch mode with the contrast at 100.

I am very happy that you are very happy and hope you are not making this experiment in vivid mode.

Believe others are not having this luck (including me) I can almost read newspaper in dark room during my tv is on 100% black
post #1229 of 11163
msalles

At what hours rise happened ?
post #1230 of 11163
Quote:
Originally Posted by kotlec View Post

At what hours rise happened ?

I turned on the TV and immediately noticed the rise. Then I checked the Service Menu and the set had 200 hours and 10 minutes.
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