This is my first post to these forums however, I'm a daily "subscriber" and have learned a lot about my Panasonic Plasma (58PZ800U) from other "subscriber's" posts on this forum.

Here is my potential Panasonic Plasma (58PZ800U) "problem / issue" and I'm hoping I can get some insight.

Here is my Home Theater setup:

*Panasonic 58PZ800U Plasma
*Panasonic DMP-BD35K Blu-ray Player
*Denon 3808ci Receiver
*DirecTv HR21-200 Satellite Receiver
*Panamax M5300-PM

First, just a little bit of history........

All power for each of my Home Theater components is run through the Panamax M5300-PM. The Panasonic DMP-BD35K Blu-ray player and the DirecTv HR21-200 Satellite receiver is connected via HDMI to the Denon 3808ci HT receiver. I also have a Xbox 360 connected via HDMI to the Denon 3808ci HT receiver and a Wii connected via Component (cables) to the Denon 3808ci HT receiver. The Denon 3808ci is connected via HDMI to the Panasonic (58PZ800U) plasma TV. All is working without any problems. I love this setup!

Last week, I finally had my Panasonic 58PZ800U plasma TV professionally calibrated. It was calibrated in the "CUSTOM" mode. The picture is phenominal when watching most HD content, watching Blu-ray movies and playing XBOX games however, sometimes some of the programming content appears to be "too bright" or "washed out". The "PICTURE" setting within the "CUSTOM" mode is almost maxed out (+97) and the "SHARPNESS" setting within the "CUSTOM" mode is high as well (+75). Prior to the calibration, I watched all content (DirecTv / Blu-ray) in "THX" mode and played video games (Xbox 360 / Wii) in "Game" mode. I had been using the recommended settings from TweakTV.com prior to the professional calibration.

Now, to the potential problem......

After reading sevaral posts in the Panasonic 58PZ800U plasma forum, I decided to change the "THX" mode settings to match the "CUSTOM" mode settings (post calibration). I watched some DirecTv content (both HD / non-HD) as well as some Blu-ray movies in the "THX" mode. That "too bright / washed out" look seemed to disappear in some of the programming content that I noticied in the "CUSTOM" mode. The "THX" mode seems more "movie-like". At the same time, I noticed what appeared to be green dots floating over the entire screen when in the "THX" mode with NO content / signal is being displayed on / to the TV. I also noticed the same problem in low-light / dark scenes (displaying dark colors, especially the black color) when watching DirecTv content / Blu-ray movies. It was very noticable from a distance right away. I wasn't seeing that deep black "picture-like" look like when the TV is shut off or in another mode (STANDARD / CUSTOM / GAME / ECT). It looked like "green" snow...almost like what you'd see when something is causing interference with the TV and again, not that deep black "picture-like" look similar to when the TV is off or in another mode. It also appeared that when the TV displayed black colors, they "floated" around the screen and often displayed different shades of black, rather than displaying a constant deep black I experienced in other scenes. I've tried different HDMI ports on the back of the TV. I'm still having the same issues with "THX" mode however, it is now only noticable from up close (within a two feet of the tv). After continuing to troubleshoot the problem, I came to the conlcusion that it's only in "THX" mode that I see this issue (I'm back to using HDMI-1 on the back of the TV). I don't get any of the above described symptoms in any of the other modes (STANDARD / CUSTOM / GAME / ECT).

Is this a defect in my TV?? Can anyone else confirm the same type of problem / issues I am experiencing (or want to try and duplicate)? I'm considering contacting Panasonic or the local retailer where I purchased the Panasonic (58PZ800U) plasma TV from (have 4yr protection plan through local retailer). Any suggestions / help / other troubleshooting techniques would be greatly appreciated.

Sorry about the lengthy post....but I feel I needed to give as much info as I could to help resolve the issue I'm having. Let me know if any additional information is needed or if something needs to clarified.

Thanks for all the replies :)

Thats the pixel orbiters.
Not a defect,

Thats the pixel orbiters.
Not a defect,

Thanks for the reply Fanboyz......

Why are they not present in other modes (STANDARD / VIVID / GAME / ECT) and only THX mode?? Should they be present even when no signal is being sent to the TV??

Thats the pixel orbiters.
Not a defect,

No, it isn't the pixel orbiter.

It sounds like PWM noise or dithering to me.

First I can't believe anyone would calibrate the 800u in custom mode. The gamma is completely messed up (which adds noise to the picture) and the colors are way off. There's hardly any reason to own the 800u over the 80 or 85 unless you use THX.

Anyway, it sounds to me like the brightness setting is a little too high. Brightness can be set a couple of different ways. One is to use a calibration DVD like Avia or DVE.

You can also use the black sidebars that you get when you have 4:3 material on an HD channel (commercials, etc). Get very close to the screen, so you can easily see the "static" that you described in the black sideabars, then lower it until it just disappears. This is really easy to do if you have a DVR -- just pause the program when a commercial comes on. You can still do it without one, you'll just have to be quick.

*BUMP*

Hoping others can provide their two cents on this issue.....thanks :)

**UPDATED INFO**

I contacted Panasonic regarding my issue of the "floating green" dots when in THX mode. Panasonic set up an appointment for a local service technician to come out and troubleshoot the issue.

On Friday afternoon, a service technician arrived and confirmed the problem I was experiencing. He used the remote and RESET the PICTURE settings in "THX" mode. After the reset, the "floating green" dots disappeared. PROBLEM SOLVED....right? WRONG. After he left, I readjusted the settings in "THX" mode to match the calibrated settings in "CUSTOM" mode. After the adjustment, I once again noticed the "floating green" dots. After messing with the BRIGHTNESS setting in "THX" mode, I was able to determine that the "floating green" dots are associated with the "BRIGHTNESS" setting in the "THX" mode. I also determined that if I lower the "BRIGHTNESS" setting to anything below +56, the "floating green" dots disappear. THIS ISSUE IS ONLY ASSOCIATED WITH THE BRIGHTNESS SETTING WITHIN THE "THX" MODE (above +56).

I also reported to Panasonic a "stuck / lit" pixel at the top-center of my screen (pinkish / purple on white background). The service tech checked on the "stuck / lit" pixel and told me not to worry about it since most plasma's have the issue. Panasonic told me they would correct the problem regarding the "stuck / lit" pixel, yet, nothing was corrected.

Is my Panasonic TH-58PZ800U defective with regards to the "floating green" dots in "THX" mode when the BRIGHTNESS setting is at +56 or higher?? It doesn't seem like I should be having this type of problem.....

Any ideas / suggestions is MUCH appreciated.

**BUMP**

Hoping for some suggestions / ideas.

Omg no its not defective. you have the brightness up too high thats why theres more dithering. lower it until theres hardly any. it should still be plenty bright and if you want any higher you should look into a LCD.

Omg no its not defective. you have the brightness up too high thats why theres more dithering. lower it until theres hardly any. it should still be plenty bright and if you want any higher you should look into a LCD.

Ding! Ding! Ding! We have a winner! :)

I wonder if he told the tech he had the tv "professionally calibrated?" If I am not mistaken, that voids the warranty. Pretty sure my Panasonic manual mentions something about picture adjustments in the warranty.

Another funny thing though, why is he making adjustments in THX mode? And why would you pay to have calibration if it already is pre-calibrated?

I knew the answer to the question even before I opened the thread was to turn the brightness down lol. There's nothing wrong with your tv.

Omg no its not defective. you have the brightness up too high thats why theres more dithering. lower it until theres hardly any. it should still be plenty bright and if you want any higher you should look into a LCD.

Actually contrast/picture controls "brightness" not the brightness control. Brightness controls black level. Weird, I know.

I wonder if he told the tech he had the tv "professionally calibrated?"

Yep..I told the tech it was professionally calibrated.

I guess I'm confused as to why this is only an issue in the "THX" mode and not any other mode (CUSTOM / STANDARD / VIVID / GAME / ect)?? It seems it should be "global" across all settings. BTW...if I turn down the PICTURE settting (+97), the "floating green" dots are still present, no matter what the PICTURE setting is decreased to. It's only when I increase the BRIGHTNESS setting (+56 or above) that the "floating green" dots appear.

Thanks for the continued replies.

It's only when I increase the BRIGHTNESS setting (+56 or above) that the "floating green" dots appear.


That's just what happens when you increase brightness above the level where black is black. I don't know what the technical term is but once you see dots or noise back off on the brightness and that's where it should be.