panasonic tcp50s30 plasma... white level adjustment, how and where?

[budwich]

So after replacing the SC in my "long running" battle with this set (recycle bin save), the set has been up and running. It has about 20000 hours on it.

In general, it is operating fine. However, trying to get the white levels down is next to impossible. Watching hockey results in a very bright ice (over driven such that lines on the ice surface are almost impossible to see). I can turn down the contrast and brightness controls to zero which helps but the overall picture then is some what dark. All automatic controls are OFF. This is in "custom" picture setting.

On my samsung plasma, there is a "cell light" control that appears to help in this domain but in the panasonic, there doesn't appear to be anything at the user level to achieve this. So the question is: what or how can the white levels be adjusted "better" on the panasonic?

[Biruslapio]

Re: panasonic tcp50s30 plasma... white level adjustment, how and where?

Eco mode and C.A.T.S. both diminish the total brightness of the panel,resulting in a much less hot running TV in my tests.
C.A.T.S. is room light dependent,there is a light sensor in front of the tv,you can put a insulating tape on it if you wish max dim.

[budwich]

Re: panasonic tcp50s30 plasma... white level adjustment, how and where?

I have turned those options off as they don't offer any viewing value.

[drussell]

Re: panasonic tcp50s30 plasma... white level adjustment, how and where?

Does holding down [VOL-] on the TV and pressing [STATUS] [STATUS] [STATUS] on the remote enter service mode on the S30 series?

The only similar one I have here is a TC-P55ST30 but it has a cracked panel, so I can't try it to check.

[budwich]

Re: panasonic tcp50s30 plasma... white level adjustment, how and where?

OK... I see a "WB adjust". I need to read what that does and how. Thanks

A quick look at the service manual indicates individual color "levels" which I assume change the "white color" itself. There are two other entries "all cut" (currently set at 80) and "all drv" (currently set at FF.... unused... ?). I assume the last two deal with the "total level of white" that one sees. Is there any issue, electrically, changing these and visually looking at the set or is there a possibility of taking out a circuit from "over / underdriving" a component area?

[Biruslapio]

Re: panasonic tcp50s30 plasma... white level adjustment, how and where?

That is white balance,to adjust the white color tone, it is for color calibration, I don't know of any service menu options that could lower the brightness of the panel in panasonics, but trying to change these "all drv" FF could maybe do that, can't destroy the TV by lowering that.
So eco mode and C.A.T.S. do nothing at all in your case? have you tried with the lights off?

[budwich]

Re: panasonic tcp50s30 plasma... white level adjustment, how and where?

CATS does "work" but I don't think that what I am after. With CATS off, the set appears to put out "full brightness / contrast" by that I mean whatever is set in the menu settings for picture and you are able to do some "limited adjustment"... meaning I can get some picture change but even at "0" (brightness / contrast), the picture still has a relatively "high white" level (darker than "normal" but not what I would expect at "0" setting). Maybe my expectation of what "0" on a plasma isn't correct.

With CATS on, no adjustment to the picture controls (brightness / contrast) appear to have any impact... kind of expected as maybe since CATS is in control.... perhaps using some form of "presets" in the service menu.

On the samsung, adjusting the "cell light" to "0" along with contrast ("0") basically gets you an "almost black" screen (just barely able to see a "grey image". That's the sort of "picture control" I am trying to find on the panasonic especially for hockey where large portions of white exist. Of course, there is also an issue with the "production cameras" where some don't appear to have proper white levels... at least that's what I have noticed "camera to camera", "broadcast to broadcast".

The only "eco" mode I see is in the "turning off the set" after a certain time of "no signal" / "no change".

[Biruslapio]

Re: panasonic tcp50s30 plasma... white level adjustment, how and where?

These options i offered change the total max brightness of the panel, i tought that was what you want, not the constrast of near white levels.
If your menu is like my P50VT20, I always max contrast and brightness is 0 or +1 for really dark stuff, at "normal" mode and standard color temperature TV can differentiate every tone from 0 to 255 level like this picture https://i.ytimg.com/vi/VJDVvYC0-aU/maxresdefault.jpg
and this is for black https://i.ytimg.com/vi/ZmpInWD8DIA/maxresdefault.jpg
If nothing helps try changing service menu settings,just remember what they were before.
Probably whatever you were watching was terribly edited/captured or your input device is modifying the constrast.
Eco mode i believe is in advanced settings, it does the same as CATS but is not room light dependent.

[budwich]

Re: panasonic tcp50s30 plasma... white level adjustment, how and where?

The user menu controls use contrast / brightness settings for each mode and input. They range from 0-100. The "issue" is that even with contrast set to 0 (basically no contrast, if that makes any sense) and brightness at 0, the image is just slightly less than "normal" meaning you can pretty much see everything and the white level is somewhat reduced but certainly not "unwatchable" so to speak. It would appear that the lower range just isn't there. Coloring is off which is expected as you move down contrast / brightness but again not what would be expected at "0" levels.

I use a Wow disc for tuning with all the test patterns. The contrast control doesn't give the full upper end on the "brighter than ideal white" (contrast set at 95-100)... but almost. So on the "full screen white", there doesn't appear to be a "clip" or "bloom" at least with the test disc. But during hockey on some broadcasts / camera, there appears to a "over exposed white" such that lines on the ice are almost invisible... you could miss the "face off circles" if you didn't know they were there. The ice itself has lost most / all skate marks in lots of the areas.

Perhaps some form of AGC has lost its way... although AGC is mentioned in some places in the internet for panasonic sets, I don't see any options for this on the set. In general, I see discussions about panasonic and the lack of controls for ABL (auto brightness limiting) which most people want none. In general, I would agree for most viewing but hockey. I guess just getting a slightly lower level by significantly moving down the contrast will be my best option at this point or using some modification to "standard" mode which has an overall darker contrast / brightness setting plus whatever is embedded in the tv for this setting.