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

Originally Posted by Slickman

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

Originally Posted by pukemon

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.

Originally Posted by ChosenGSR

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.

Originally Posted by pukemon

have you called panasonic and told them about it yet?

Originally Posted by mmoh00

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.

Originally Posted by Turrican4D

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.

Originally Posted by Bdemers

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

Originally Posted by mmoh00

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.

Originally Posted by xrox

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)

Originally Posted by Gov

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

Originally Posted by mmoh00

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?

Originally Posted by xrox

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)

Originally Posted by robi1138

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

Originally Posted by xrox

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.

Originally Posted by robi1138

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?

Originally Posted by Slickman

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

Originally Posted by Syed117


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.

Originally Posted by kotlec

At what hours rise happened ?