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Burn In

Burn-in ... Phosphor burn ...  Screen burn.  Note that this is not the same as the "break-in" period for new equipment.  Burn in, phosphor burn, or screen burn are terms that describe cases when certain parts of the screen exhibit uneven wear from the rest of the viewing area.  An analogy/demo might help. 

Place a wide piece of paper on a window so that the paper covers the window and the excess covering the window frame/wall. This kind of mimics a 4:3 frame on a widescreen.

After a few days of exposure, remove the paper. You will notice that the area exposed is faded and the two sides not exposed are not faded. You should be able to discern the line of demarc between the faded and unfaded.... burn-in.

By making the bars gray on the set, enough energy is being sent to the unused portion of the screen to help keep up with the wear on the rest of the screen. The wear rate will admittedly be different but should still help prevent burn-in. If the bar is turned black, then you increase the difference in the wear rates which consequently would also make it more visible. 

A simple graphic is given below to illustrate the effect of burn in (exaggerated for demo purposes):


Different wear rates cause the gray/black bar areas to be a bit brighter than the rest of the screen.   

I have seen this at a local dealer and its looks very disturbing.  You can't ignore it.  It' not something you get used to over time.  Since you see it when you look at the screen, it is very very annoying/disturbing.  So, beware.

Here are a few quick notes on burn-in from video specialist Mr Bob:

  • Keep Contrast down to a max of 75% of the light level your eyes tell you your TV can do. 50% is even better, during the first 100 hours. Your phosphors are brand new, and very virgin. They need to be treated as such, with lotsa TLC.
  • CRT phosphors have very predictable lifespan, and can be nursed to be virtually as bright as ever for 10-15 years, if handled right. A brand new RPTV will have phosphors that are ultra-bright for few months, of course, and if you want to dazzle yourself silly, you can. But it will come off the brightness capacity of your TV at the other end, years down the line, if you do. Adjusting room lighting accordingly is a much better way of handling the desire for an ultra-bright picture.
  • NO FIXED IMAGES, for any length of time, EVER! This means video games with fixed borders, ticker tape bands, menu images, strong bright logos like MSNBC...
  • If these fixed images are necessary -- say you run stock ticker tapes all day on CNN or whatever -- turn you Contrast down low. If just burning in your brand new RPTV and not watching it during lengthy periods of time, turn your Contrast down to ZER0. Phosphors are not what is needed to be exercised, during burn-in.
  • To preserve your phosphors after the burn-in period, keep contrast down low when viewing non-visually-challenging material, like Jay Leno's monologue every night. You don't really need to see the picture bright and crisp and clear and dazzling in cases like this, and not constantly pushing your phosphors to be always at their brightest will increase their lifespan in later years, down the line.
  • Don't just run the TV for 100 hours straight. Expansion and contraction due to heat up and cool down are a strong part of a TV's burn-in, and must be honored. So make sure that no matter how much you run it during the daytime, let it get absolutely cold overnight before you start it up again next day.
  • Following these procedures will allow you to safely burn-in your new RPTV in a matter of days, if necessary.

Keep your contrast low for the first 100 hours, no more than 75% of what your eye tells you your TV can do, and NO EXTENDED-TIME FIXED IMAGES. EVER. No MSNBC, no fixed-image/border video games, no ticker tape reports burning that band into your phosphors. You'll have your hands full, probably, just keeping the black/grey bands from being seen on your screen while bright and white images are there after awhile, due to the mixing of standardized aspect ratios in this crossover era between NTSC and HDTV.

If you absolutely have to have fixed images up there for any length of time, turn your contrast low for the duration, and save the bright images for when you're watching something really spectacular. I even keep my contrast low when I watch Jay Leno's monologue every night, turning it up for the better parts of the program. Brightness is not the bugaboo on burn-in, Contrast is. Brightness, a misnomer, controls the background darks; Contrast controls the foreground bright areas.