Why grey (not black) bars on plasma TV?

[admin_exported]

Newbie alert.... my first post so...

Helped my mother in law pick out a new TV recently, settled on a 37" Panasonic plasma. Nothing fancy, 1024x768 res but she only watches SD so it's does the job.

But, when watching 4:3 content and not streching it to fit the 16:9 screen, the sidebars are distinctly grey, not black - why?

When the screen is off it is much more deep dark grey so clearly these sidebars are not pixels in total "off" mode. Now considering the never ending "screen burn" discussion, would it not be better to have black bars (i e pixels off) than grey which I assume means they are activated, displaying this grey shade?

Can the side bars be forced to black? Is this is a setting on the TV?

Again, sorry of this is 'dumb' questions but I have searched all around for a straight answer and found none.

EmKay

 

[Andrew Everard]

Sounds like the brightness and/or contrast are set incorrectly. I'd adjust them until the bars were as near to black as you can get them. Could also be that you've got some picture-enhancement on - TVs tend to come out of the box set to 'dynamic' or something similar. Try going into the picture modes and selecting 'natural' or the equivalent.

 

[Anonymous]

I think that comes under p.33 of the manual under display settings "side panel". Manual says the recommended setting is high to prevent panel image retention, which I think is the grey bars. You should be able to set to off so it just displays black bars at the side when watching 4:3. If it's not that I'd give Panasonic a ring and they should be able to talk you through it...

 

[Sorreltiger]

This came up on another thread yesterday. ÿI have just looked up the definitive answer for my Pioneer PDP-4280, which can be set to 'Auto' for side masks:

" The "Auto" setting adjusts the brightness of the side masks according to the brightness of the screen and can reduce the possibility of image retention."

ÿIn other words, the aim is to reduce the contrast between the picture and the bars, avoiding sharply defined 'active' and 'inactive' portions of the screen. ÿPerhaps your Panasonic has something similar?ÿ

 

[Anonymous]

Hmm... this seems counter intuitive.

How can the plasma panel retain something that isn't there? It would seem to me that grey bars (activated pixels) would be more prone to retention than black bars (non active pixels).

Very puzzling indeed.

EmKay

 

[Anonymous]

do the black bars represent the deepest possible blacks a tv can produce?

 

[tvmog]

EmKay:

Hmm... this seems counter intuitive.

How can the plasma panel retain something that isn't there? It would seem to me that grey bars (activated pixels) would be more prone to retention than black bars (non active pixels).

Very puzzling indeed.

EmKay

I think it is nore about long term iimage retention (if that is the technical term) in the actual 4:3 picture area. If you watch a lot of 4:3 with the side panels switched off (ie black) then the pixels in the picture area are used more than the pixels at the side. As the pixels fade with use over a long period of time a difference in the intensity of the two ares will eventually become noticable when watching in widescreen mode.The grey side bars ensure that all ares of the screen are active for approx the same length of time - at least thats my laymans understanding of it.

 

[D.J.KRIME]

EmKay:

Hmm... this seems counter intuitive.

How can the plasma panel retain something that isn't there? It would seem to me that grey bars (activated pixels) would be more prone to retention than black bars (non active pixels).

Very puzzling indeed.

EmKay

The reason the side bars are set to grey is to help reduce any possiblity of permanent image retension, if they were black then the differance in contrast between the unused side aera and the viewing area is far greater than if they are set to grey. A possible result if they are set to black could lead to a visible "center box" where to 4:3 image is displayed permantly being visible on the screen.

A simular but temporary result can sometimes be seen after viewing a movie in 2.35:1 where on a black screen you can make out on screen where the the black bars were but this clears very quickly and is nothing to worry about.

IMHO in normal use if you wish to set the side bars when viewing 4:3 to black rather than grey you should be ok but this is dependant upon just how long you view 4:3 material for at a time, the longer the time the higher the risk.

 

[Anonymous]

EmKay:
Hmm... this seems counter intuitive.

How can the plasma panel retain something that isn't there? It would seem to me that grey bars (activated pixels) would be more prone to retention than black bars (non active pixels).

Very puzzling indeed.

EmKay

I have it on GOOD authority that the black pixels are indeed active.

So the grey bars would be a better option I guess.

 

[Anonymous]

I'd thought it was so that screen fade was uniform. Thought that over time (albeit many many many hours of viewing) the screen would fade. And if you'd watched lots of 4:3 with black side bars then the middle section of the tele would have a duller image than the outside edges. So that when you did watch 16:9 progs you may find the edges brighter than the middle. Not sure where I read that, or if it's true. But I can't quite see how you'd get image retention from black bars?

 

[Anonymous]

piobob:

I have it on GOOD authority that the black pixels are indeed active.

So the grey bars would be a better option I guess.

OK - well I am still puzzled how a black pixel (not emitting any light) can be considered active but hey I'm no rocket scientist

My very personal opinion is that the grey bars distract tremendously. Perhaps I am the only feeling that way but I doubt it. I am about to buy a new large (46-50") TV for the living room and this one major issue for me with plasma screens. I don't think I could get used to looking at images framed by grey bars, either on the sides (4:3 content) or at the top and bottom (2.35:1).

EmKay

 

[Anonymous]

D.J.KRIME:
The reason the side bars are set to grey is to help reduce any possiblity of permanent image retension, if they were black then the differance in contrast between the unused side aera and the viewing area is far greater than if they are set to grey. A possible result if they are set to black could lead to a visible "center box" where to 4:3 image is displayed permantly being visible on the screen.

OK - sounds very plausible, thanks!

But I still dislike seeing those grey rectangles... Guess it's shaping to LCD for me.

EmKay

 

[Anonymous]

EmKay:piobob:

I have it on GOOD authority that the black pixels are indeed active.

So the grey bars would be a better option I guess.

OK - well I am still puzzled how a black pixel (not emitting any light) can be considered active but hey I'm no rocket scientist

My very personal opinion is that the grey bars distract tremendously. Perhaps I am the only feeling that way but I doubt it. I am about to buy a new large (46-50") TV for the living room and this one major issue for me with plasma screens. I don't think I could get used to looking at images framed by grey bars, either on the sides (4:3 content) or at the top and bottom (2.35:1).

EmKay

I've had my Pioneer for 5 months, and I must admit I was concerned about the grey bars too. I don't think about them now.
It's surprising how soon you get used to it.

 

[D.J.KRIME]

EmKay:D.J.KRIME:

The reason the side bars are set to grey is to help reduce any possiblity of permanent image retension, if they were black then the differance in contrast between the unused side aera and the viewing area is far greater than if they are set to grey. A possible result if they are set to black could lead to a visible "center box" where to 4:3 image is displayed permantly being visible on the screen.

OK - sounds very plausible, thanks!

But I still dislike seeing those grey rectangles... Guess it's shaping to LCD for me.

EmKay

Why on earth would there be any differance on a LCD over a Plasma? As I have said if you dont like the sides being Grey then simply set them to Black.

The side boxes are there for 4:3 on either a Plasma or LCD the same as the black bars at the top and bottom of the screen are when viewing 2.35:1 , these bars if on the side or top and bottom are there due to the ratio of the image not matching the ratio of your screen and not due to what type of technology your TV is made from.

On a Plasma the side bars can be set to black on most LCD sets you will be able to see the backlight shining through on the sides when viewing 4:3 in its native ratio. When watching 2.35:1 the bars are black not grey.

 

[Anonymous]

D.J.KRIME:
Why on earth would there be any differance on a LCD over a Plasma? As I have said if you dont like the sides being Grey then simply set them to Black.

OK OK.... I was assuming it was more "safe" to use LCD as this would totally eliminate any potential burn issues.

EmKay

 

[D.J.KRIME]

EmKay:D.J.KRIME:

Why on earth would there be any differance on a LCD over a Plasma? As I have said if you dont like the sides being Grey then simply set them to Black.

OK OK.... I was assuming it was more "safe" to use LCD as this would totally eliminate any potential burn issues.

EmKay

How long roughly at a time would you watch programs in the 4:3 ratio?