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Discussion Starter · #1 ·
My apologies if I this has been asked before but I couldn't find anything in a forum search.


I've had two 50ST60s. Both floor models...one with 2,700 hours on it...one with 800. Both had various degrees of pink tint in the upper center of the screen with greenish edges. The higher mileage one seemed worse but I never really compared them side by side so it's hard to say.


I only notice the uniformity issues during normal content when a relatively large section of light blue sky is displayed or when displaying bright white or higher IRE gray full screen slides. I NEVER see it when running the Panasonic screen wipe (a high contrast white bar about 1/4 to 1/3 of the screen width that scrolls left to right across a black background). I have windowed calibration slides but since they are centered in the screen they don't overlap the area that I associated with the worse of the uniformity.


The combination of the factors above make me think that the color issues only appear when the ABL is needed. Would this make sense at all? Considering the nature of how these sets work? This is my first plasma and I don't really have a frame of reference. Normally I'd say the issue is associated with bright portions of the picture that don't mask the red push in that section of the screen well but if that was the case I'd expect to see it on the screen wipe.


Thanks in advance for any knowledge you can drop on me.
 

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yes fullscreen white fields uses the most power so its only there you see it.

the problem: uneven wear out and to low voltage to the panel.


the main power controller for the panel must be raised.

the typical name is VS or V SUS


some can set it in the service menu.

if you dont have that setting in the service menu there is voltage regulators that can be raised.
 

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Discussion Starter · #3 ·
Thanks pg_ice. I actually have VSUS set to high in the service menu and it seemed to help some. Based upon what I was reading in the VT50 forums (I'm told this ST60 is similar to that model) some folks were discussing the voltage regulators you mention.. I'm not quite ready to crack open the back panel yet.
 

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Be careful that may or may not be the issue, if you have a warranty contact panasonic. I have close to a 1000 hours on my ST60 and none of those issues, also have a Vt60 with 3300 hours no uniformity issues like that.
 

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Quote:
Originally Posted by chunon  /t/1520120/can-the-abl-kicking-in-cause-unformity-problems#post_24416809


Be careful that may or may not be the issue, if you have a warranty contact panasonic. I have close to a 1000 hours on my ST60 and none of those issues, also have a Vt60 with 3300 hours no uniformity issues like that.

you can't just compare hours.

its all depends on what content you have watched and what brightness/power saving modes you have used.


issues on a white field is wear out.

that panel needs more power.


cantact panasonic= replacement of the whole panel?


what a waste when you can fix it yourself.
 

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I own that model do you ? So your advice to someone under warranty is to open up their set and adjust the voltage themselves ? Bad advice imo


And when he bricks his tv or electrocutes himself you are going to replace his panel and pay for his medical bills ?
 

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Discussion Starter · #7 ·
My set was a floor model. One of the last in the area from what I can tell. I have a one year warranty, but it's not like they would be able to replace it. Besides while two sets with the same issue was a small sample it was enough to convince me that a perfect panel is not likely (especially when you consider current low inventory levels). It really only shows up in content that I would consider a torture test of sorts. Especially after I did a DIY calibration with an entry level meter.


From what I read on the VT50 forums there is a Low VSUS and a High VSUS adjustment under the back panel and it sounds like the delta between the two settings isn't always high enough to eliminate the issue. I'd almost go in after it, but I don't own a stand so adjusting then testing would be a real pain in the butt (and I'm otherwise VERY pleased with the picture quality). But that may be an option if it gets worse.


I've had low voltage at our outlets in the house before according to my multimeter...would it be worth it to try a power conditioner? I assume not since the TVs power supply would normally compensate for a slightly lower input voltage.
 

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I am sure they have panels and of all the ST60 owners this is the first I have heard of this issue. I do not believe it is common at all. But its your set go with what you think is best, if it were me I would try to get a new panel out of it.
 

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I agree with chunon and I am not convinced the VSUS will fix the issue anyway.


However, are you seeing this issue with real content? A little bit of uniformity issue could show up on test patterns and can be normal. My ST30 had some and was improved after a greyscale calibration as Panasonics do tend to push/drift more red over time unless kept in check.


My VT60 does have better uniformity though compared to my ST30.
 

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Discussion Starter · #10 ·
I don't think any of the advice given in this thread has been out of line. I was just curious about the behavior more than anything and didn't initially associate it with the VSUS posts I was reading regarding the VT50.


I guess after years of owning a Sony SXRD that I'm leery of replacement parts (they are often worse than the originals) and I don't think Panasonic is going to do anything other than offer me a replacement LED or a refund (neither is acceptable). And this is after convincing a repair guy that it's even an issue (Best Buy thought I was crazy for returning the first set and it's already back up for sale on their clearance website).


I was just surprised to see any unformity issues AT ALL since this is my first plasma and that is supposed to be one of their strengths. But then I'll see a random comment on the internet like 'Panasonic hasn't made a completely uniform panel in years' that seems to associate the marketing need for thinner panels that use less power as the root of the issue I'm seeing. So it's hard to know what to believe.


But the voltage issue makes sense. The panel looks great otherwise and if I get a smaller white patch in the center of the screen it has no red push. I can even watch black and white films without any visible issues.
 

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You sound like you are a lot more handy than me
Congrats, for you it is probably good advice but for the average owner it is irresponsible advice imo. As David mentions uniformity issues seen on color slides is alot different than something you can see in real world content. According to the internet there is a Chupacabra roaming Kentucky and killing livestock
I put more weight on the experience of actual owners vs others that have an agenda against one company or the other. The calibration solution is a valid one too since abl does alter gamma response and color balance, if it is already out of whack abl is going to make it worse in some cases.
 

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Discussion Starter · #12 ·
No worries either way. There is a lot of old talk on this issue in the VT50 forums and it sounds like the ST60 is just a trickle down VT50 panel from the previous model year. Not that I mean this as a knock on Panasonic...it was nice of them to bring the previous flagship to the mainstream. . I just never associated it with ABL because they didn't really suggest that connection from what I saw in those other threads.


As far as being more handy I don't know about that. Maybe enough to be dangerous. I collect pinball machines and I had to learn to fix them becaause they are collector items that aren't really manufactured anymore. Kind of like a Panasonic plasma is becoming.
I've also worked in tech support and found that a dedicated enduser may often be more aware of issues than the 'professionals'. They certainly have more incentive to resolve issues than a customer service rep might.



I may play around a bit with the calibration but I don't think it's something that can easily be adjusted for. If it only shows up when the ABL kicks on then I can't really calibrate to that since it's never going to happen with a windowed calibration slide. And it would be foolish to calibrate to peak load on the panel. I think I will look for a few more patterns that have white around the screen without enough to kick in the ABL though. If I get uniformity there I'll just leave it alone.


Ultimately I'm pretty pleased with the set. I think it's the best 50 inch available for the price I paid ($600). The only other one I would consider would be the F8500 and not at their current retail price.
 

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I had the VT50 with the blobs btw so as a point of refererance I know what to look for and thus far nothing like that on my particular ST60. Pinball machines that's a cool hobby
 

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Discussion Starter · #14 ·

Quote:
Originally Posted by chunon  /t/1520120/can-the-abl-kicking-in-cause-unformity-problems#post_24417575


I had the VT50 with the blobs btw so as a point of refererance I know what to look for and thus far nothing like that on my particular ST60. Pinball machines that's a cool hobby

The VSUS adjustment is supposed to be a pot on the circuit boards. Considering the fact that no one can be bothered to make a sidelit LED that doesn't have light bleed around the edges that it is within reason that these small knobs are not perfectly adjusted at the factory on all sets. So your set is probably adjusted within proper tolerances and mine is a hair off. It wouldn't surprise me...gadgets are such a race to the bottom nowadays. And manufacturing tolerances aren't what they used to be.
 

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Discussion Starter · #15 ·
So I booted up my copy of AVSHD709 and ran the contrast test pattern under the ColorHCFR section. Alternating white and black chessboard. Doesn't look like enough to get the ABL going and the white squares are uniform all over the screen. To the eye at least. I haven't tested with a meter.
 
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