Panasonic 50VT50B ( Dithering or Sparkles? )

[Moreno83]

Hey guys ,

First of all , what a tv! Picture quality is amazing and its not even calibrated.
Im having some "problems" with it though....

Is this plasma dithering or are these sparkles? Pictures are made from close range but its everywhere on the screen , not just some area.
Vsus voltage using potmeter is 114V , have not changed it as i dont want to ruin my tv.
Vsus in service menu is set to low ,im afraid to change it.

Sparkles are not viscible from a normal distance , I know this is the way that plasma's work but if you look closely it looks "bad". Is this the beginning of the end?
Or does this tv need a little tweaking?

[Moreno83]

Re: Panasonic 50VT50B ( Dithering or Sparkles? )

When i choose AV1/AV2 the picture is perfectly black.
Changing it back to HDMI and the sparkles return. Going to buy a new HDMI cable and see if that changes anything.

Also downloaded a blu ray and played it via USB. On dark scenes the sparkles are visible from a normal viewing distance.....
Going to open the back cover of the TV tomorrow and change the voltages.


Any thoughts?

[tw2005]

Re: Panasonic 50VT50B ( Dithering or Sparkles? )

well i highly doubt Vsus is 114V but if that's what your meter says I would not trust the meter.

Is this the VT50 with a ST50 main?

[Moreno83]

Re: Panasonic 50VT50B ( Dithering or Sparkles? )

I was thinking the same , it should be like 128v right? Cant find anything about it in the SM but im sure i measured 114V with my Fluke meter.

Service manual says Vsus Low = 110V , Vsus high = 115V , what does this mean?
Im going to open the back cover of the TV tonight and see if i can adjust it. There is no sticker with the Vsus/Zsus. ( or its covered somewhere ).

Will let you know what im measuring.

[tw2005]

Re: Panasonic 50VT50B ( Dithering or Sparkles? )

I was thinking the same , it should be like 128v right? Cant find anything about it in the SM but im sure i measured 114V with my Fluke meter.

Service manual says Vsus Low = 110V , Vsus high = 115V , what does this mean?
Im going to open the back cover of the TV tonight and see if i can adjust it. There is no sticker with the Vsus/Zsus. ( or its covered somewhere ).

Will let you know what im measuring.

serious, let me have a look at that manual first because that's about 100v shy of any panasonic plasma I've worked on

[tw2005]

Re: Panasonic 50VT50B ( Dithering or Sparkles? )

on a ST50 I see 210-215V, very much doubt your info.

and this is the Vt50

[Moreno83]

Re: Panasonic 50VT50B ( Dithering or Sparkles? )

Sorry , your absolutely right. Took another meter and its 213V.

[Moreno83]

Re: Panasonic 50VT50B ( Dithering or Sparkles? )

It does look like sparkles right? Its mostly visible on black area's.

[tom66]

Re: Panasonic 50VT50B ( Dithering or Sparkles? )

This is dithering and is normal. I have the same on my 9G Kuro although it's more noticeable.

[Moreno83]

Re: Panasonic 50VT50B ( Dithering or Sparkles? )

So its normal to see those sparkles on meter distance? Its not like , ow lets look very closely and search for sparkles. Its really visible....

I downloaded Interstellar Blu-ray ( 15GB ) and played it via USB and the black area looked really bad. Alot of sparkles/dithering.
Dithering is normal but not THIS much?

[Moreno83]

Re: Panasonic 50VT50B ( Dithering or Sparkles? )

Vsus was 214V and changed it to 210V. Vda a little higher and dithering is back to normal.
The dithering still looks bad when i watch a movie via USB. ( dark area's and you see sparkles ).

[tw2005]

Re: Panasonic 50VT50B ( Dithering or Sparkles? )

Vsus was 214V and changed it to 210V. Vda a little higher and dithering is back to normal.
The dithering still looks bad when i watch a movie via USB. ( dark area's and you see sparkles ).

I don't think playing with vda is a good idea as that goes to the C boards and those lower panel ribbons with the chip on film which if damaged will write the tv off

[Moreno83]

Re: Panasonic 50VT50B ( Dithering or Sparkles? )

Changed it back but it was almost set to the max already.

The sparkles/dithering is only visible on "normal" mode. Its not there on Professional1/2 or Cinema/THX mode. But i dont like the picture on the other settings , they are all very dark or a yellow tint. In normal mode the colours are really nice and punchy but its something in "normal" mode that causes the dithering.

Will try and tweak the profesional mode and see what happens.

[tw2005]

Re: Panasonic 50VT50B ( Dithering or Sparkles? )

Changed it back but it was almost set to the max already.

The sparkles/dithering is only visible on "normal" mode. Its not there on Professional1/2 or Cinema/THX mode. But i dont like the picture on the other settings , they are all very dark or a yellow tint. In normal mode the colours are really nice and punchy but its something in "normal" mode that causes the dithering.

Will try and tweak the profesional mode and see what happens.

I don't recall seeing a max for vda, factory set, would not adjust. not even sure if they give that voltage in the manuals these days.