Ditto Impaqt's comment. I have seen the 4:3 burn-in on a set less than six months old. I have not seen logo burn-in, but I am sure that is just because my clients generally include several family members, so the channels and inputs get switched quite often.

Left at factory contrast settings, plasma monitors will suffer premature phosphor aging. 'Burn' is relatively rare, but aging that causes the phosphor moloecule to be less efficient, or less bright, is very common.

I've seen it act 'temporarily' overnight on a few sets, were you can faintly see an impression on a black or white field, but then it recovers...as if the phosphor has a slight memory of the static image.

I've seen it 'permanent' on sets used in the 1.33:1 mode over an extended period of time.

ANY company that claims some sort of correction is merely accelerating the aging of the phosphors outside the 1.33:1 image by reversing the polarity of the image...if you can watch it, the image is like an old film negative...and the side bars are unused, or black...so they don't age along with the inner rectangle. It does NOT fix the problem, only average the wear and tear so it is not as noticeable. Most times, a line at the edge of the 1.33:1 image still exists...

I don't know where those 30k hours halflife come from...I'd LOVE to see the official document on that one, but a Hollywood insider (SMPTE color expert) told me that he got a half life figure of 4k hours on a popular Japanese brand...I don't want to be vague, but will NOT publish figures that I haven't confirmed.

Cheers,
John

John

30,000 hours, here it is in print. Zenith also prints this number in consumer lit.

[Link: plasmavision.com]

we fitted 4 nec plasmas to a bar 5 years ago, which are running 15 hours a day, 7 days a week, (that's about 19-20,000 hours) and so far we haven't seen any screen burn and have had no problems at all.
Haven't got any permanent screen burn in any of the plasmas we've fitted yet