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Is CRT Burn-In Still a Problem?
coloth asks: "We've all been told for many years that monitor burn-in is a thing of the past, that CRTs use a different kind of phosphor now, and that screensavers are more toys than practical safeguards. After a few minutes with Google, nearly every PC advice site I found said as much. Well, I just realized tonight that I've got burn-in from the Seti@Home screensaver on my Dell P991. I took a picture with my digital camera. (disregard the bar of interference) I added the arrows with PhotoShop and enhanced the image a bit, but the burn in is clear. Here is the image of the "screensaver" to compare the pattern. Is my monitor sub-par? Is the conventional wisdom about burn-in untrue? Are most people doing anything specific to avoid burn-in?"
Every computer at my (ex)university had that same problem. Seti@Home (And, actually, all of the distributed-computing project 'screen savers') make extreamly POOR screen savers. If you're going to set it up like that, you should enable the "turn monitor off" option if your monitor is capable. (Saves electricity, too)
=Smidge=
Apparently plasma screens are particularly suceptible to screen burn, and the so-called 'DOG' (Don't know what it stands for, it means the logo of the station/programme you're watching) often gets burnt in if you watch one channel frequently. The displays in the BBC TV newsrooms used to show this effect, but they've either been replaced or recalibrated.
I just wish they'd stop cluttering *my* screenspace.
-Yarn - Rio Karma: Excellent
I've seen the line "PowerMenu has shut off the screen to prevent burn in" (paraphrased) burned into each of the 25 text lines on a monitor. The program moved the text between lines to prevent burning in one line, and burned in 25 lines instead.
Top two images most often burned into monitors: WinNT/Win2k "Press Ctrl-Alt-Delete for a secure login." and the BSOD. :-)
My desktop monitor has the outline of the /. main page burnt on it. o_O~
Yes, Virginia, phosphors do wear out over time. The problem used to be much, much worse.
... turn the darn monitor off for a power consumption of maybe 2 watts (off doesn't quite mean off). A friend and I went to ridiculous lengths during the California energy crisis to persuade his tech company IT dept. to tell everyone to turn off their 3,000 machines when not in use, or at least overnight, or AT LEAST over the weekends and holidays.
... they could upgrade the O/S ... but what they have works. There are cheap utilities that persuade NT to play along, but that would require getting the IT people to install it, and if they were unwilling to listen about turning monitors off, well.... you get it.
:)
I hate screensavers that run more than ten minutes -- they rarely seem clever any more, and more importantly they seduce a lot of people into thinking they are somehow saving energy. In fact, if the tube is fired up the box is consuming nearly full power and releasing nearly full heat.
MUCH better is any kind of sleep mode, which might reduce a 75-watt load to 5 watts. Or
They told workers to leave them on because of the old tale that electronics last longer that way. More research, I eventually reached a very friendly engineer with the Sony monitors operations. In short, the leave-'em-on philosophy made some sense before all solid-state surface-mount design prevailed because of thermal shock and "creep," which made IC's rise in their sockets. Now everything is soldered and the components are many times more reliable. In terms of monitor wear, it's probably a toss-up. No one would seriously leave their TV on 24 hours a day to save money, right? And even if wear were accelerated somehow with the machines on 1/3 as long, the amount of energy consumed would have bought a ton of hardware.
We calculated the excess electrical in the hundreds of thousands of dollars, and that's before factoring in the added load of the air conditioning to remove the waste heat (most of the energy used goes to waste heat). (A rough guess: the best estimate I could find suggested it takes 1 watt of A/C consumption to remove 3-4 watts of heat.) There was also a citizenship issue to energy conservation at the time, as there were rolling blackouts to ration energy the closer the system came to overload. (You all remember the stories.)
Um, anyway, I hope I made a point. Er, my point. One thing Apple did right was to support Energy Star early on. "By design," MS Windows NT 4.0, which his company uses, does not support power mgmt even though the newer monitors typically do. Yes
I think they did start telling employees to turn the monitors off just recently, maybe 18 months after our email campaign and a half-million in electricity. Could the computers be next? They're just dumb workstations and don't do anything in the off hours.
Last nail in the coffin: To give you a sense of his IT department, they sent a tech down once who could not be made to understand, by several engineers, the difference between a SCSI and a parallel port ("Well, it should fit."). No shit.
AFAIK, the screensavers in xscreensaver don't burn anything in, because they keep things moving enough.
/etc/X11/xdm/Xsetup_0 I've added the lines:
But if we're going to gripe about pollution, Big Oil, and the like, we should be using DPMS. It's not tightly linked to APM or ACPI, or other power-saving features. It's right there in X.
For my example, in
"/usr/X11R6/bin/xset s noblank s 200 60"
"/usr/X11R6/bin/xset dpms 300 1800 2400"
The first line puts the good old X screensaver into action, and the second line handles DPMS. The three DPMS numbers are the times when progressive power savings kick in. By having these lines in the xdm configuration, you get the screensaving features even at the xdm or gdm login. (Gdm symlinks to Xsetup_0, I don't know about kdm.) By the time the third powersaving mode kicks in, your tube uses about as much current as a night light.
The flipside of burn-in is cathode poisoning. That happens, or happened, when the tube is blanked, but still active. I don't know if it's still a problem with modern tubes. But it takes so little to avoid, why not. That's why I kick the X screensaver in, and turn off blanking.
The living have better things to do than to continue hating the dead.
They should put a button on the front of the monitor that would make the screen turn off. It would save electricity and prevent any screen burn in too!
Glonoinha the MebiByte Slayer
Note that the shape of the burn in matches that big, bright blue diving bar thing in the SETI@HOME screensaver screen capture.
Karma: Excellent (fuck, even in the future moderation doesn't work!)
SETI@home has a built in option to blank the screen (without turning off the monitor or doing any fancy Energy Star stuff) after a certain amount of time. They even recommend this because the video code takes some time away from the CPU. There's no excuse for not using this.
Omnes arx vestrum sunt adiuncta nobis.
I've seen an entire lab of computers with the Windows 2000 login box burned into the monitor of every single one. This may be something of an extreme case, since the displays were left on 24x7, even on nights and weekends and they were relatively cheap monitors to begin with, but burn-in is certainly still a reality.
The bottom line is that it probably doesn't matter if you leave the same thing up for a little while, but the screen should definitely be blanked/turned off the it isn't going to be used for any significant period of time - say, a half hour or more. Besides eliminating the problem of burn-in, simply turning the display off when it isn't in use will save a significant amount of energy.
If you really want to burn something in to a monitor, follow these instruction.
:)
NOTE: These instructions should not be done by anyone with an IQ under 100. This will damage your monitor! That's the whole point! Permanantly! In fact, no one should ever do this. Except maybe cats. Cats are weird like that.
1. Boot into a console (or DOS on a differently-abled system) I think you Mac users are out of luck (yet again), seeing as you can't exit your GUI.
2. Write a batch file or script or something that clears the screen and puts out ANSI codes for high intensity white, and your message wherever you want it on the screen.
3. Open up your monitor*. Find the flyback transformer. It has a big red wire coming out of the top of it most likely. That red wire has 20,000 or so volts running through it, be careful, it bites.
4. That transformer likely has two adjustment knobs on the side of it, which probably have screwheads for phillips head screwdriver. They are called focus and screen adjustments, they are variable resistors.
5. Use whiteout to carefully mark the original position of the focus and screen. If you don't know which is which, it's OK, you will find out as soon as you turn one of them.
6. Slowly and carefully turn one of them while the monitor is running*, and make sure you can see the screen. If it goes out of focus, you have the wrong one. Slowly turn it back to your white-out marked position. If it gets brighter or darker, that's the one you want.
7. Turn up the front panel brightness all the way. Then turn the screen knob up slowly until the black part is pretty light too. The white text should be extremely bright right now, and may bloom some. Don't turn the knob up so much that the X-ray protection kicks in*. If the CRT turns off, you went too far, dipshit. Try rebooting the monitor if you didn't fry anything.
8. Once you have the black level so it is pretty bright, and the text is nice and bright but not blurred out completely, let that thing sit for a few hours. Keep an eye on it, but don't hang out in front of it, X-rays, remember?
9. Try turning the monitor off and see if the phosphers are cooked yet. If you can see the text with the monitor off, then you have succeeded.
10. Undo all the changes you made to the settings. Put the cover back on. Any leftover screws are a bonus from the Gods. Sell the monitor to your enemy, etc.
*In case you havn't noticed, if you screw up, you might die. This whole thing is dangerous for someone who doesn't know their way around electricity. Don't be a dipshit, and don't do this on a monitor you don't want to destroy. In fact, just don't do this... ever!
Oh BTW... to the original poster, you can't reverse burn in by displaying a reverse image. All you will do is burn the rest of the phosphers to the same darkness as the burned ones, and your monitor will get too dark to use sooner.
I've had enough abrasive sigs. Kittens are cute and fuzzy.
Let me get this straight.
Until recently you didn't believe in CRT burn-in, but you became a believer while looking for freaking space-men?
Your system of beliefs is totally fucked.
-Peter
Even on old world machines (beige G3 etc) Mac OS X ignores the GUI code in the ROM as it is a completely different architecture (QuickDraw rather than Quartz) and it would be pretty impossible to use from a Unix environment anyway.
Logging in as >console drops you into a text console. No GUI. Is that so hard for you to believe? If you hold down command+v, Mac OS X will boot in verbose mode ie. it dumps pages of text to the console just like linux does. Command+s will boot you into single user mode, which is sh with nothing else running and / mounted as read only.
Here's a trick: install XFree86, login as >cosnole, run startx. No Apple GUI code in sight. Hell, if you had half a clue you'd know that Apple releases Darwin free without Quartz et al. The console is all you have unless you install XFree86.