First, lets define just what "burn in" is. CRTs and Plasmas both use phosphors to display an image. What actually happens is that an area that is comstantly used for the same static image for a long time will tend to burn out those phosphors and the image will not be as bright as the rest of the screen. Given that, if you displat 4:3 all the time with black bars, the center of your screen will age faster than the sides. That is why they have the neutral gray bars that you can put up to prevent this. Do not confuse burn-in with image retention that you see when going from a bright scene or a menu to a very dark scene. THis is much like a fluoressant bulb does when you turn it off. This goes away in a few seconds and in not at all harmful-irritating, but not harmful.
Most plasmas have some sort of circuitry built in to reduce the chance of burn in. I do not know where that 100 hour thing came from, but even after 100 hours, you will still use the center of your screen more than the edges if you display a lot of 4:3 and that part of the screen will age faster. I have read that if you do no more than 15% of your viewing as s static image like bars and banners, that burn in is never a problem. Personally, when viewing 4:3, I use the gray bars or stretch it. On DVDs that are not 1.85:1 aspect, I just do not worry about it since it is such a small portion of my viewing.
...Only way to go. Pretty much confirmed what I think it's fair to say we all knew. nothing comes even close except for huge direct view CRT sets that max out at 36" and weigh over 200 lbs.
Best plasmas rated at 70.
Best "microdisplays" (including DLP, LCoS, LCD-RP) rated at 61.
Best direct view LCD's (and here was the biggest surprise) rated only 52(!!!).
This report (in this month's CR) alludes to the presence of "rainbow effect" in pretty much every DLP and the horrible viewing angle limitations in all but direct view CRT and (of course) plasma.
Simple conclusion here. Anyone looking for a screen between 42" - 55" would be insane to get anything but a plasma.
I was going to add "unless absolutely forced by budget to consider alternatives" but I decided that the truth is if that's the case, just wait a couple of more months until you can afford the plasma.
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