Pan TH-42PHD7UY Black level changing - Page 7 - AVS Forum

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OLED Technology and Flat Panels General

BlazeMaster's Avatar BlazeMaster
08:10 PM Liked: 10
post #181 of 449
01-26-2005 | Posts: 720
Joined: Mar 2004
techniwizard, where u at, has the bird shed any light lately?

one question for you, since you seem like u know alot about plasmas. I met a guy who owns a little AV store near where I live and he told me he can add a 12-bit video proc. chip to Pioneer, Panasonic and sony's. I'm wondering if you heard of people doing tweaks like this to PDPs? He said the cost difference between a 10-bit and 12-bit chip is less than a $1 and not sure why most PDPs still utilize the 10-bit. He'll add one on whatever PDP I go with and will charge about $100. He sounds like he knows alot about the AV stuff and showed me his Colorfacts (ISF?) certificate. I didn't get a good look to see the certificate, but he sounds like a trustworthy guy. Would the chip help the existing 42HD7UY problem? If not, am I likely to see an improvement in the overall PQ?
Techniwizard's Avatar Techniwizard
11:21 PM Liked: 10
post #182 of 449
01-26-2005 | Posts: 1,220
Joined: Oct 2001
Blaze,

Sounds a little bit like snake oil to me.

FWIW I have a Colorfacts ISF cert as well, you buy the test gear and you get one unless his is something else again...

Most of that $100 is (should be) labor. These ICs are surface mounted PIAs to change out.

Shot in the dark, try to ask for part numbers (so you can research the specs) between the original and the proposed "new" IC.

I don't think that will have any effect on the brightness thing but then again, it might be worth $100 to find out.

T. Wiz
caeguy's Avatar caeguy
07:08 AM Liked: 17
post #183 of 449
01-27-2005 | Posts: 1,246
Joined: Apr 2004
IMHO, I still think there may be a problem with the new added features of this set.

This is taken from the owners manual.

Symptom

The screen darkens slightly
when bright pictures with
minimal movements are shown.

Check

The screen will darken slightly when photos, still images of a computer or other pictures with minimal movements are shown for an extended period. This is done to reduce after-image on the screen and the shortening of the screen's service life: It is normal and not indicative of malfunctioning.
gadgetfreaky's Avatar gadgetfreaky
08:30 AM Liked: 16
post #184 of 449
01-27-2005 | Posts: 677
Joined: Jan 2003
so this strobe effect is "normal"

I wish I could ignore it. But now I obsess over it. i don't want to mention anything to the wife as I don't want her to start noticing it..
gadgetfreaky's Avatar gadgetfreaky
09:10 AM Liked: 16
post #185 of 449
01-27-2005 | Posts: 677
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Can we add on the title of this thread the 50 7UY? I think it would be very helpful since many are assuming this is only on the 42" issue. I tried starting a seperate thread but it was merged with this one.

should I start a new thread again if that can't be done?
spa's Avatar spa
09:17 AM Liked: 10
post #186 of 449
01-27-2005 | Posts: 458
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I don't think it is a problem with the added features of this set. It doesn't happen on the 42PWD and it doesn't happen (with one noted exception) with the 50PHD. Note that the description says "shown for an extended period". The brightness changes we're talking about occurs immediately upon change in image content and can change several times over just a few seconds time. That doesn't fit the troubleshooting description.
Dale Pickle's Avatar Dale Pickle
09:57 AM Liked: 10
post #187 of 449
01-27-2005 | Posts: 72
Joined: Jan 2005
Has anyone experienced this problem with the consumer version of the set?
caeguy's Avatar caeguy
10:00 AM Liked: 17
post #188 of 449
01-27-2005 | Posts: 1,246
Joined: Apr 2004
Quote:
Originally posted by spa
I don't think it is a problem with the added features of this set. It doesn't happen on the 42PWD and it doesn't happen (with one noted exception) with the 50PHD. Note that the description says "shown for an extended period". The brightness changes we're talking about occurs immediately upon change in image content and can change several times over just a few seconds time. That doesn't fit the troubleshooting description.
But maybe that function is not working properly. What if there is a bug in the firmware that defined "extended period" to a fairly short period. e.g. "X"ms?

Just throwing out some thoughts.
exrace's Avatar exrace
10:12 AM Liked: 10
post #189 of 449
01-27-2005 | Posts: 22
Joined: Dec 2004
I am hoping this is a setting a service menu will shut off.
I haven't heard anyone talk about access to the "service menu" for the 42HD7UY.
I know the service menu is not for consumer use but would be helpful to see what is tweakable.

I am very aware of the "burn in" issues and would shut off this "protection" if there was the option to do so.

I am not sure if I am off base on this comment but I only see this on certain resolutions.
I am trying to compile a list of the stations and modes the panel is using to see if this has any correlation.
dusty144's Avatar dusty144
01:15 PM Liked: 10
post #190 of 449
01-27-2005 | Posts: 304
Joined: Sep 2004
My 50 7uy does not show this. And it is a simply fabulous picture. Its an Oct 2004 Japan product.

I understand these issues but people who refuse to buy the set sight unseen are doing themselves an injustice. The NEC's come with their own set of issues that we don't discuss enough on this forum.

My biggest one is that NEC has withdrawn from the market except for marketing, Pioneer essentially runs the show. How long before the NEC's get merged into Pioneer and the resulting support limbo.

Also very few have done head to head comparisons between the two. Some of those who have, have rated NEC's very negatively. IMHO the panny's are quite simply in a class of their own. If you put 5 different panels side by side there will be no doubt of this.

Please keep in mind that Panny owners out number NEC 20 to 1 atleast. For every unhappy customer there are a hundred who don't say anything.

End Rant:eek: :eek:
rmaier's Avatar rmaier
01:58 PM Liked: 10
post #191 of 449
01-27-2005 | Posts: 14
Joined: Nov 2004
Quote:
Originally posted by caeguy
IMHO, I still think there may be a problem with the new added features of this set.

This is taken from the owners manual.

Symptom

The screen darkens slightly
when bright pictures with
minimal movements are shown.

Check

The screen will darken slightly when photos, still images of a computer or other pictures with minimal movements are shown for an extended period. This is done to reduce after-image on the screen and the shortening of the screen's service life: It is normal and not indicative of malfunctioning.
IMHO, it may be a problem with the new feature set, but I don't think this "feature" is it, because the issue (from my viewing experience) is the _reverse_ of the effect described above - i.e. the screen/black levels *lighten* slightly, not darken, when a bright object moves into an otherwise dark scene.

This is why it doesn't appear to be (at least from my viewing experience on my 42PHD7UY) that it is connected with a screen saver or power saver or power supply issue gone wrong, unless the "gone wrong" part is to have it act in reverse of its intended effect.

For the record, I still love everything else about the screen, and my initial experience with Visual Apex was great.

Rob
sebbarre's Avatar sebbarre
02:01 PM Liked: 10
post #192 of 449
01-27-2005 | Posts: 19
Joined: Dec 2004
Quote:
Originally posted by dusty144
My 50 7uy does not show this. And it is a simply fabulous picture. Its an Oct 2004 Japan product.
Well the fact is, the problem is there and potentially with any 50" UY Pana you can buy, since many of us have noticed it. Our testimony is a little bit more relevant though, as we can prove the problem is there, we have seen it, it's reproducible. On the other hand you can not really say you do not have the problem since you might not have used your Pana in the same way (i.e. inputs, connection, material, etc.). What I mean is that there is a chance that you might just have been lucky (but I hope you just do not have the problem at all of course). Also note that I definitely don't disregard the fact that it might be a combination of the Pana *and* the signal that is sent to it or the device connected to it (i.e., maybe my STB outputs HD signal that makes my Pana behave that way).

I assumed you tried HD, SD, though Component and eventually HDMI/DVI ? As I said, this will definitely depend on the material, do not expect to see that on baseball games. I'll try to come up with a list of DVDs that can be used to reproduce it. I haven't had the time to watch DVDs on my Pana yet, but I had some HD shows taped on my DVR, and the phenomenon was deterministic, it would happen each time I looped over it (allowing me to try different settings, without success). What are your picture settings, by the way (and power management settings too) ? Eventually, I will have to dig in the service mode :(
peter_moy13's Avatar peter_moy13
10:53 PM Liked: 10
post #193 of 449
01-27-2005 | Posts: 168
Joined: Oct 2003
It may be helpful to list the time codes in DVD's this effect may be noticed. I'll try to post some exact data this weekend.

But for now, anyone with the Terminator 3 DVD can jump over to the scene in the cemetery where Clair Danes is talking with the psychologist in the back of the ambulance. The camera point of view is from inside the ambulance looking out at the doctor with a bright sky framed by the ambulance door. As the doctor moves his head around, I can easily see the letterbox bars jump around in brightness. Easily repeatable for me if I step thru the scene frame by frame.

The brightness in the letterbox area actually "holds" (remains constant) if you leave it frozen on a bright frame. My picture setting is -11 and brightness at -8 with sharpness at 5. All other settings are default with no advanced options.

If I had to venture a wild guess, the panel is doing some sort of average brightness calculation of the entire scene to determine how "black" to make the dark areas. As soon as a certain threshold (amount of whiteness) is exceeded, the entire black level is bumped up a notch. Same thing in reverse, thus the reports of the "strobe effect" as the scenes change.

Whew, I really wrote much more than I wanted to. Hope it makes sense, I need some sleep.

-Pete
spa's Avatar spa
07:54 AM Liked: 10
post #194 of 449
01-28-2005 | Posts: 458
Joined: Apr 2003
Quote:
Originally posted by sebbarre
Well the fact is, the problem is there and potentially with any 50" UY Pana you can buy, since many of us have noticed it. Our testimony is a little bit more relevant though, as we can prove the problem is there, we have seen it, it's reproducible. On the other hand you can not really say you do not have the problem since you might not have used your Pana in the same way (i.e. inputs, connection, material, etc.). What I mean is that there is a chance that you might just have been lucky (but I hope you just do not have the problem at all of course).
In my case I can conclusively say my 50PHD does not have the problem because I had the problem with a 42PHD and retested those scenarios using the same signals on the 50PHD. I hope you think my testimony is relevant ;). Given my experience with it I'd believe someone who said it wasn't there. I encountered it under a variety of inputs and circumstances. It would have been wonderful to have found a way to avoid it, but it didn't seem possible.

Pete, I wrote down a scene where it occurred early in this thread: The Empire Strikes Back at around 5:32. its the scene where Han is telling the general he has to leave Hoth and the following argument with Leia. There were several times during that scene where the brightness changed, and not always when the overall brightness of the image changed.

We need to take a survey of 50PHD owners before we can say that "many of us have noticed it". We've got gadgetfreaky and sebbarre are you saying you've encountered it too? Obviously I'm not on that list.
gadgetfreaky's Avatar gadgetfreaky
08:21 AM Liked: 16
post #195 of 449
01-28-2005 | Posts: 677
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Well, we'll see in this post.
http://www.avsforum.com/avs-vb/showt...69#post5076669

I decided to start a seperate post for us 50PHD owners that have this problem. those that have the problem, please come over and post.
dusty144's Avatar dusty144
08:30 AM Liked: 10
post #196 of 449
01-28-2005 | Posts: 304
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Quote:
Originally posted by sebbarre
Well the fact is, the problem is there and potentially with any 50" UY Pana you can buy, since many of us have noticed it. Our testimony is a little bit more relevant though, as we can prove the problem is there, we have seen it, it's reproducible. On the other hand you can not really say you do not have the problem since you might not have used your Pana in the same way (i.e. inputs, connection, material, etc.).
Are you willing to settle for the fact that it is inconsequential to me. I'm not going to go looking for problems when I could spend my time enjoying the picture. I often watch my TV in pitch black too with no bias lighting at all. You guys call it a strobing effect which scares everyone and then in the next sentence you say it is a very subtle effect that you have to look for.

I am concerned that this board has not become a "find a problem with the Panasonic" zone. This is very unfortunate as people are definitely making decisions based on some of this. I'm not an uninterested Newbie, I like a high quality image with the next person and yes my panel does have the DVE brightness problem documented elsewhere. But as I have stress repeatedly the this does not in anyway affect my enjoyment of the image.

While you may find this irrelevant, seems someone must provide some balance, no...

P.S.
In my book and in that of the vast majority of the less analytical consumers this would fall under the category of quirk rather than 'problem'. If you can't stand the quirk return the panel and then deal with NEC's quirks. Don't immediately start off on a "Panasonic must fix this" hunt.

This is a discussion group, not a QA panel.
gadgetfreaky's Avatar gadgetfreaky
08:38 AM Liked: 16
post #197 of 449
01-28-2005 | Posts: 677
Joined: Jan 2003
sorry for the wishy washy statement. i guess a part of me doesn't want to admit that my $5k plasma has a problem. I don't have to "look" for the problem, it's there. it's just subtle and if I consciously ignore it, I don't think abou ti. Like I said, my wife hasn't said anything. But it's definitely there. I say strobing effect, as it alternates but it's usually 1-2 seconds of bright, then dark. And it doesn't happen 100% of the time, just during certain darker scenes or shows. it is reproduceable on the tivo, meaning if i see it and skip back to the same scene, it's there again.
sebbarre's Avatar sebbarre
09:54 AM Liked: 10
post #198 of 449
01-28-2005 | Posts: 19
Joined: Dec 2004
Quote:
Originally posted by gadgetfreaky
sorry for the wishy washy statement. i guess a part of me doesn't want to admit that my $5k plasma has a problem. I don't have to "look" for the problem, it's there.
Exactly the same here. I don't have to look for it, it's there. I will invite some folks over and check if they notice anything (without telling them first). And of course do some DVD testing. I don't have any of the DVD you guys mention so far, but I've plenty others we can test :)
calhokie's Avatar calhokie
10:20 AM Liked: 10
post #199 of 449
01-28-2005 | Posts: 353
Joined: Jun 2003
snippets of quote...

Quote:
Originally posted by dusty144
Are you willing to settle for the fact that it is inconsequential to me. I'm not going to go looking for problems when I could spend my time enjoying the picture. I often watch my TV in pitch black too with no bias lighting at all. You guys call it a strobing effect which scares everyone and then in the next sentence you say it is a very subtle effect that you have to look for.

While you may find this irrelevant, seems someone must provide some balance, no...

As a potential buyer, I disagree. I have enough common sense to understand that there are many, many happy owners. And that the problems seem to be subtle and isolated to certain conditions. I don't need anyone to be a Panasonic cheerleader. I've seen the various brands and I'm leaning towards getting the Panasonic when I pull the trigger in about a month. The Panasonic and Fujitsu are the only plasmas I have seen with a good enough black level to buy them.

Also if you are discussing the "balance" of viewpoints, I've found many of the NEC comments have been "blacks look fine to me" and "I haven't calibrated yet but the TV looks great". Not exactly hard empirical data, I'd much rather hear somebody (preferably ISF trained) say you can still pick out details down to a certain level. I duvetyne'ed my HD RPTV to get better black levels so they are a big concern to me (and blacks were a big reason why I didn't consider a plasma 18 months ago) and I can say that the Panny has blown away all of the competition in my budget range (although I'd still like to own my buddy's Fujitsu).

I appreciate what you are trying to do, but trust me that I'm savvy enough to sift through the information and not dismiss a great plasma because of S-Video difficulties in the 0 to 7.5 IRE range. I want to know these problems so I can try and buy hardware to mitigate or eliminate the problem.
sebbarre's Avatar sebbarre
09:29 PM Liked: 10
post #200 of 449
02-02-2005 | Posts: 19
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*TEST PERFORMED: HERE IT GOES*

I'm posting this one in the "Problems with Panasonic 7UY Series" thread too, since it's where the following test was suggested.

I have recorded a specific HD show ("Austin Stevens: Snake Master") that I can use to reproduce the "Black Level Changing" / "Stobing" effect a couple of people and I have noticed on the 50" 7UY.

I performed the following test:

- I looped over the exact same segment using HDMI input, Component Input, and Component-To-VGA input.

- In each case, when available, I tried to have my DVR output 1080i, 720p, 480i and 480p.

- In each case, I also tried to tweak the picture settings to reduce the strobing problem.

The conclusion is, for my 7UY:

=> I could notice the *exact* same problem on every inputs and on every type of signal.

=> the best way I could adress the problem was by setting "Advanced Settings" to On and "Black Extension" to a value >= 3. There is no magic here, it pretty much reduces the details in the dark areas, making them darker, and making the "stobe" less obvious. Reducing the "Brightness" will do that too, but I noticed that changing the "Black Extension" would impact the overall brightness less (i.e. would focus on the "blacks").

=> I watched a good chunk of "Star Wars 2: Attack of the Clowns" through Component (480p), and the picture was fantastic. I focused on dark scenes with bright elements popping up, and I could not notice any strobing effect. I also tested several XBox games through Component-To-VGA (480p), and the picture was phenomenal. This is, of course, puzzling, and I'm starting to suspect either my DVR/STB (Scientific Atlanta 8300HD), or the HD show itself, since I have *not* noticed the strobbing problem on SD material (say, the new "BattleStar Galactica" show on SciFi for example).

My settings are/were (I used the Avia DVD to perform basic calibration):
- Picture: 15
- Brightness: 0
- Color: -2
- Tint: 0
- Sharpness: 0
- Color Temp: Normal
- Color Management: OFF
- Advanced Settings: OFF

Note: some people suggested I was smoking about the HDMI blade and 480i material. Sorry folks, the blade documentation says it all, and I checked it *again* tonight, it will *not* accept 480i signal. Nada. All other inputs will/did.
jadolley's Avatar jadolley
04:32 PM Liked: 10
post #201 of 449
02-05-2005 | Posts: 23
Joined: Nov 2004
All

I finally have a resolution. It took a while but so far I am a happy camper. I was able to "uptrade" my unit for a HD507UY. So far I have not seen the black level issues on any input (S-video,Component, or HDMI). I just got done with it today, Saturday, so I will have to keep an eye on it. Have to go out tonight, will have more time for testing tomorrow, which in my case is just observation.

Thanks Visual Apex, Techniwizard and spa!

Jim
Techniwizard's Avatar Techniwizard
06:57 PM Liked: 10
post #202 of 449
02-05-2005 | Posts: 1,220
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HI Jim,

Glad to hear it worked out.

TW
spa's Avatar spa
07:19 PM Liked: 10
post #203 of 449
02-05-2005 | Posts: 458
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Jim,

I'm so glad to hear you've got a things worked out. I'm certainly hoping Panasonic will get a resolution to that problem soon, but it is nice to just sit and enjoy the display instead of worrying about the problem, isn't it. Enjoy!
sebbarre's Avatar sebbarre
08:32 PM Liked: 10
post #204 of 449
02-05-2005 | Posts: 19
Joined: Dec 2004
Quote:
Originally posted by jadolley
I finally have a resolution. It took a while but so far I am a happy camper. I was able to "uptrade" my unit for a HD507UY. So far I have not seen the black level issues on any input
So let's see... Maybe I should downgrade my HD507UY which has black-level changing issues for one of the 42 that does not have...

Kidding (yet, mine still has the issue).
BlazeMaster's Avatar BlazeMaster
10:43 PM Liked: 10
post #205 of 449
02-05-2005 | Posts: 720
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I know I asked this before, but on the VA's website in the Return Policy section: one of the last few paragraphs stated that any Panasonic PDPs can be returned after a short conversation with VA. I dunno what you guys had to deal with when you found out that you have the black level problem, but they still didn't allow a full refund even though there seems to be a exclusion for the return policy strictly for the Panasonic PDPs? I'd like to have this unit, but worried that they won't let me return this if the problem occurs on my unit.
rmaier's Avatar rmaier
02:37 PM Liked: 10
post #206 of 449
02-25-2005 | Posts: 14
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I am bumping this topic to see if anyone out there has an update and the changing black level issue. With over twelve thousand views, this topic apparently holds some interest to those who own afflicted machines, as well as those on the purchasing fence. If you know anything, please chime in.
sweatynipples's Avatar sweatynipples
04:54 PM Liked: 10
post #207 of 449
02-25-2005 | Posts: 100
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has anyone contacted panasonic directly?
gladesteen's Avatar gladesteen
10:10 PM Liked: 10
post #208 of 449
02-25-2005 | Posts: 56
Joined: Dec 2004
Add another one to the black level blues :(

Mine does not happen during a light or dark scene, however.
Sometimes it has a mind of its own and does it whenever it feels like it.
In other words, the screen could be showing a still picture and the black bars would change from light to dark and vice-versa.

All my settings have been checked, then checked again.

Mine was purchased from Plasma Concepts. I have not called them yet with the bad news. Panasonic needs a fix for this ASAP!! It is annoying!!
rlshky's Avatar rlshky
02:48 PM Liked: 10
post #209 of 449
02-27-2005 | Posts: 59
Joined: Nov 2003
I had the problem, and there was no fix for it.
Icon Smith's Avatar Icon Smith
03:40 PM Liked: 10
post #210 of 449
02-27-2005 | Posts: 491
Joined: Feb 2005
I was a heartbeat away from ordering the Panny unit after reading all the good reviews on various sites - then I stumbled across this thread. Now it's no way jose as far as this model is concerned.

So, back to the selection process. Any suggestions on an alternative model? I was considering the ED model TH-42PWD7UY - and still am primarily because of the superior black levels - although I really would prefer an HD unit. What about other Panasonic HD models, or perhaps Pioneer ...or Sony?

It looks like the Panny TH-42PX25U/P is still available, but the TH-50PX25U/P has been discontinued without an equivalent replacement, so I assume the 42" is following suit as soon as inventory is depleted. I really don't want to get a model that is discontinued even before I get it.

Also looking at the Pioneer PDP-5045HD which gets pretty good reviews, but the black levels aren't on par with the Panasonic units - not that any other manufacturer will be - and it is kind of pricey. Money isn't my biggest concern, but of course it is a factor.

Any suggestions on a "can't lose" 42 - 50" model?

Thanks,
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