I have scouted all over the internet to read literature about Image Retention and Screen Burn from the past few days as i bought 51D550 plasma and here is what i found out from experts and also analyzing comments of normal users :-
1) First 100 to 200 hours break in is a "necessity" for any plasma as it fundamentally necessary for the way plasma technology works. (Newer plasmas are have a lot less risk but still its better to do atleast 100 hours)
2)IR and Screen burn in modern plasmas occur only by "extremes" and not normal use. Thats why most people never notice it.
3)"Extremes" in plasma terminology means having a static image for hours and hours at end and doing the same for days. Static image might be just one part of the screen like the network logo or HUD in a video game or worse the welcome screen of a dvd player left on by mistake. Also to some extent the black bars in top and sides when watching a 2.35:1 movie in letterbox mode or 4:3 in letterbox mode.
4) Screen burn in risk is reduced by more than 90% after "break in" period of the plasma
5) Newer plasmas might sometimes have Temporary Image Retention but almost never Permanent burn in !
6) All companies including Samsung & Panasonic DO NOT COVER IN WARRANTY THE DAMAGE TO PLASMA TV DUE TO SCREEN BURN IN OR IMAGE RETENSION (It is specified in the first page itself of the manual which came along with my 51D550 Plasma TV)
Break in Method:-
(Very simple but takes a couple of weeks or a month max, then we can enjoy 10-15 years life of the panel)
* Reduce the brightness and contrast below 50 and choose "movie" mode or equivalent ( Burn in and IR almost never occurs when contrast and brightness is low)
* 80% of the time watch 16:9 content. (Do not watch 4:3 letterbox mode and try to avoid 2.35:1 as much as possible and stretch all videos to 16:9)
* Run the Scrolling screensaver(built in almost all modern plasmas) or other break in screensavers all through the night so that you can reach 100-200 hours fast.
* Ideally 10 hours break in a day would be gr8 (8 hours scrolling screensaver at night and 2 hours of viewing)
*Do not spend more than than 10% of time playing video games, watching CNN,NDTV etc or channels having Ticker or ESPN etc having fixed scoreboard until 100 hours and 30% until 200 hours.
*Even if watching above, switch channels during advertisements and while playing video games take a break for 5 minutes after every 20 mins.
*Use as much of 3D as possible(Except 3D gaming) for 200 hours !! 3D has a lot of activity and gives a lot of exercise for the phosphors as it has to display 2 frames in the time of 1 and also because 2 slightly different images are being displayed, the possibility of burn in is drastically reduced.
* Avoid using it as a PC monitor. icons, taskbar etc not good for plasma. ( If you want to use tv as a pc monitor much of you time then avoid plasma altogether )
I know this is seems a bit technical but once we do all this and break in the plasma in 2 or 3 weeks or a month max then we can enjoy incredible picture and gr8 3D and big screen and gr8 value for money !!!
Note:- Do not let people who do not know about these things handle your plasma during initial 200 hours, also educate your family members. Most simple thing is to tell them to change channels during an advertisement so that network logo does not get retained. Tell them to change to Doordarshan as it has logo on the left side while most channels have on right side, so changing to it during advertisement automatically gives protection against burn in.
