Quote:
Originally Posted by Eric H
I would expect that given time it will leave a mark on the phosphors, not so much damage as it is normal wear, the black areas won't wear at all.
Does it really matter though if the set will never have to show a 4:3 picture again?
|
I was referring to a CRT TV (not HD) with no cable box that is left on, showing a 4:3 image (with the black bars above and below, of course), some 13+ hours a day. Of course, the image would burn itself into the screen if it were stationary and left on the screen any length of time, but with moving images such as football games and other normal programming, I would think the chances of screen burn are quite slim. The TV networks would not leave their logos showing at the lower right or left corner of the screen if there was a chance said logos would burn themselves into that screen. I once asked a representative at Time Warner Cable (my area's cable provider) about this issue and was told that there is no danger of the logo burning itself onto the screen, since the TV picture itself is constantly moving even if the logo isn't.
VK member RCA2000 brings up a valid point regarding LCD screens. Yes, it is possible to burn an image into these screens if a stationary image is left on said screen any extended length of time (this is why the small "no signal" info box on most HDTVs is set to move around the screen after a very short period of time with no input signal); however, with normal programming where the images are moving, I don't think there is a problem.
DVD players also have screen savers that cause the manufacturer's logo to move around the screen if there is no video signal, again to prevent or at least minimize the possibility of a screen burn. My LG Blu-ray player has such a screen saver, and I am sure most other makes of Blu-ray and even standard DVD players have them as well. Imagine the public outcry that would result if these safeguards were not present in DVD/Blu-ray players and flat-screen HDTVs--most manufacturers would be facing lawsuits that could put them out of business in a hurry as soon as the complaints of burned screens started coming in. Most instances of screen burn in FP HDTVs are the result of leaving stationary images on the screen and forgetting about them, the same as the old CRT sets. The latter also had problems with ion burns which would damage the screen; however, once again, the main cause of screen burn with these sets was leaving stationary, bright images on the screens for extended periods of time.
Four-by-three TV programming, made long before HDTV, 4K, etc. were even thought of, is still shown on the retro TV networks (Antenna TV, RTV, MeTV) and even some independent broadcast channels, which often results in a picture with black bars above and below the image. With a flat screen this can be compensated for by the zoom function; just press the button on the remote or the set itself until the image fills your screen. However, with an older CRT set, of course, this is impossible. TVs built for the 4:3 NTSC broadcast standard do not have provisions for increasing the raster size; even Zenith sets with "Zoom" or older sets with a picture-size switch to expand the picture vertically cannot hide the black bars, and even fiddling with the height and linearity adjustments won't cause a 16:9 image to fill the screen, due to the nature of high-definition. Some stations show programs that are presented in 16:9 format that cannot be zoomed in on. I have seen this on the NBC affiliate here in northeastern Ohio; the picture will not fill the screen horizontally, and no amount of pressing the zoom button on my TV remote will bring in a full picture. These are regular TV programs, mind you, not commercials. I don't care what the TV programmers do with the commercials, but when I see a TV program that cannot be zoomed to the size of my screen, I wonder what they must have in mind.