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Discussion Starter · #1 ·
Hello, I'm new here so I apologise if this is in the wrong place, but I was wondering if anyone could help me identify what is going on with the blacks on my new TV. Its an LG PB690V which is as far as I am aware is an EU variant of the LG 6600/6900 series plasma TVs.

Anyway, in the best way I can explain it, it has this greenish static or noise that covers darker areas of whatever scene is being displayed.

Deep blacks seem fine but colours slighly lighter than black start to exhibity these weird meshes of sparkling pixels that follow the darker blobs of colour around the screen. They're not stuck pixels, because they shift and move with the scene. Through some initial research I figured it might be the plasma panel process of trying to create shades of grey but mine looks far worse than screenshots I have seen.

Apparently this should also be imperceptible unless you are sitting right up close to the TV, but what I am seeing is visible (though mitigated) at 6 or 7 feet away. Some suggestions I saw in other threads included turning down the brightness and trying some calibrations settings posted here on the forum...neither of which have eliminated or even reduced what I am seeing.

I should mention I have this TV hooked up (via HDMI to the TV PC Input) to a PC running an NVidia GTX 770 GPU. I was basically planning to use it play movies from the PC. I've tried setting different pictire modes and scan modes and altering the various visual settings both on the TV and from the graphics control panel on the PC but I'm still getting it.

I'm not even sure if this is actually a problem, but if it is something plasmas 'just do' then I'm not sure I can live with it. I will be trying another input source (A PS4) and a new HDMI cable tomorrow to check those variables but I figured I'd check here to see if anyone can tell me what this is.

I've attached some pictures of the problem. They are a bit dark (had to disable flash) but you can make out the weird static ghosting in the areas of dark-but-not-quite-black colour.

Anyway, I'd appreciate any input. Thanks.
 

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Sounds like dithering in near black, try lowering your brightness 1 or 2 clicks.
 

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Discussion Starter · #4 ·
Sounds like dithering in near black, try lowering your brightness 1 or 2 clicks.
Yeah, I've already tried messing with the brightness.

I can lower it and the noise/sparkling seems to recede but it doesn't go away unless I turn the brightness down so far as to make the screen very dark.
 

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In case you don't know brightness sets the black point, contrast the white point. You really need to set brightness with a pluge pattern. Gamma controls how quick the set comes out of black.
 

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Agree with chunon, but that looks quite horrible! Not sure if that is standard fare on the LG? I certainly see a green dithering pattern on my Samsung plasma, but even 2 - 4 ft away it blends into pretty much a uniform gray shade. The posted dithering pattern looks unusually heavy and also not very random in distribution.
 

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Discussion Starter · #7 ·
I was going to try the AVS HD-709 calibration disk next. would that be sufficient to get the brightness/contrast balanced correctly and see if this is still as bad?
 

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Try various inputs; is it there in OTA or DVD/BD playback? How's the internal pattern look? How about the Picture Wizard screens?

This looks like the noise I saw in my US panel when viewing in a dark room. Adjusting the pots on the PWBs helped lower the black level and eliminate the noise, but that's not for the faint of heart, or those with defects on a new panel.

I'd contact LG about it, after verifying it's not source-dependent...

HAve fun,
Frank

PS Picture Wizard has the tools for basic contrast/brightness/color/tint set-up; a built-in calibration disk that I like very much!
 

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Discussion Starter · #9 ·
Try various inputs; is it there in OTA or DVD/BD playback? How's the internal pattern look? How about the Picture Wizard screens?

This looks like the noise I saw in my US panel when viewing in a dark room. Adjusting the pots on the PWBs helped lower the black level and eliminate the noise, but that's not for the faint of heart, or those with defects on a new panel.

I'd contact LG about it, after verifying it's not source-dependent...

HAve fun,
Frank

PS Picture Wizard has the tools for basic contrast/brightness/color/tint set-up; a built-in calibration disk that I like very much!
Yeah I've read a little into the process of those adjustments. This is brand new and within warranty so I'll likely contact LG first and see if they send out a tech that can do it for me.

Don't want to void warranty a week after purchase :(

I'll have a PS4/blu-ray player to test with in the next couple of days as well as another HDMI cable so I'll check that out first. It's just a pain trying to find the time with being in work every day.

Then I'll try calibrating properly with the disk from this forum.

After all of that I'll kick up a fuss with LG ha ha.
 

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Discussion Starter · #10 ·
I did try that built in Picture Wizard, as well as settings a few users posted on here but the result is what you see in the images I posted!
 

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I did try that built in Picture Wizard, as well as settings a few users posted on here but the result is what you see in the images I posted!
I see you are in the UK. Can you not return the TV at your store for an exchange?
 

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Discussion Starter · #12 · (Edited)
I see you are in the UK. Can you not return the TV at your store for an exchange?
Yeah it's possible.

I'll try a few things first and if I can't improve the picture I'll likely return it. I can't unsee it now.

* I have just checked and I have another two weeks to return this no questions asked, and they'll even collect it free of charge.

As I said, I'll try a few things first but I might be leaning towards sending this back now :(
 

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Yeah it's possible.

I'll try a few things first and if I can't improve the picture I'll likely return it. I can't unsee it now.

* I have just checked and I have another two weeks to return this no questions asked, and they'll even collect it free of charge.

As I said, I'll try a few things first but I might be leaning towards sending this back now :(
Might be worth checking the same TV out at a store and trying to play similar content (or carry a USB stick with some test pictures that you have tried on your set) to compare. That way you can figure out if it is specific to your TV. Don't forget to set the floor TV to Movie mode and tweak down some of the picture settings to make it an apples to apples comparison.
 

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Agree with chunon, but that looks quite horrible! Not sure if that is standard fare on the LG? I certainly see a green dithering pattern on my Samsung plasma, but even 2 - 4 ft away it blends into pretty much a uniform gray shade. The posted dithering pattern looks unusually heavy and also not very random in distribution.
Agree with Orion-- at first it sounded like normal black dithering but the pictures look quite terrible. It may be something more.

Even on my 720p plasmas the dithering looks nothing like that-- bring a flash drive, or even better, a blu ray or DVD player with an HDMI cable and run it at the store. Dont wait, dont play around with cal discs-- unless you are doing some weird trickery with your photos I dont think a cal will help at all. Is this a 720 or 1080p model?
 

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Discussion Starter · #15 ·
This is a 50" 1080p model.

The signal being sent from my PC is 1920x1080 @ 60Hz and the picture mode the TV is reporting is the same.
 

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This is a 50" 1080p model.

The signal being sent from my PC is 1920x1080 @ 60Hz and the picture mode the TV is reporting is the same.
Theres no way the dithering should be that obvious on a 720p panel, much less a 1080p one. Again, its hard to sit here and diagnose the problem from a few dark blurry pictures, but that REALLY looks fishy to me. This is not something plasma owners "just deal with". We are used to great pictures in bright and dark scenes. There looks to be something wrong with your set. Bring it back.

I dont own a LG, but 3 Samsungs-- that said , we have a 60" wall mounted LG 1080p plasma in a conference room at work, and it makes a great picture from all I have seen.
 

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Might not make any difference, but I wonder if maybe applying ferrite cores to the power cable can help? My 51" Samsung came with three.

But yeah, I too notice green dithering on dark gray on my display, but nothing like what I see in these pictures. It is only from up close, and goes away pretty quickly as I move away.

I agree that if you can not find a solution to this, it is not something you should live with. Getting it back to the store to compare other sets might be best.
 

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Discussion Starter · #18 ·
Okay.

I've tried with three separate input sources (PC, PS4 and iPlayer from TV apps) and three separate (and new) HDMI cables in different input ports.

Problem persists.

Even with calibration and severely lowering the brightness, all it does is shift this green sparkly mess to other areas of the screen that are still dark grey-ish.

I'm going to call the retailer tomorrow and get them to take the TV back.
 

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Discussion Starter · #19 ·
Might not make any difference, but I wonder if maybe applying ferrite cores to the power cable can help? My 51" Samsung came with three.

But yeah, I too notice green dithering on dark gray on my display, but nothing like what I see in these pictures. It is only from up close, and goes away pretty quickly as I move away.

I agree that if you can not find a solution to this, it is not something you should live with. Getting it back to the store to compare other sets might be best.
Using the ferrite cores was one of the first things I tried to no avail.
 

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If you are in the return period, return the tv. What you are seeing is not normal. If you are outside the return period, call LG and get a tech out. You may have an issue with one of your boards.
 
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