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LCD Color Corrector? 75

colorContrast asks: " I've currently got a Viewsonic VG700b, and as of recent, it has been giving me some trouble. Instead of showing real black, i'm now getting a red hue for black, and the pixels on the screen have become more pronounced than they used to be. The odd thing is that when I brought my monitor home over vacation, the problem was fixed for a short while, but now it appears to be broken again. Does anyone have any suggestions on if its time to get a new LCD, or if they know of a fix for this problem? (I have attempted to manually correct it by changing the colors but that did little.)"
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LCD Color Corrector?

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  • by Anonymous Coward
    Have you tried using tinted sunglasses? It might be kind of awkward, but if you can find the right shade, it would be cheaper than replacing the screen :p
  • For starters, take off your rose tinted glasses.
  • I think your monitor is broken. Save yourself the trouble of trying to "fix" it through color corrections or otherwise and either get it professionally repaired, or buy a new one.

    Of course, you could just have a bad cable (thinking along the lines of a broken VGA cable... can wash out colors when you lose 1 of the 3....)
  • Sears has the tool you need right here. []
  • Don't bother. (Score:4, Insightful)

    by Pig Hogger ( 10379 ) <pig.hogger@gmail.NETBSDcom minus bsd> on Tuesday February 14, 2006 @06:15PM (#14719836) Journal
    LCDs are notoriously poor colour renderers, compared to CRTs.

    It is nearly impossible to have uniform backlight illumination, so you will always have colour variation problem. And the pixel intensity response is not gammaifiable like CRTs, and is bound to vary along the screen.

    If you expect your LCD to do photo-edition, you're SOL.

    • He wasn't asking whether to get an LCD or CRT monitor. He already made that decision. He is currently having a problem with his LCD monitor that he didn't have previously, so obviously the problem is not something intrinsic to all LCD monitors or his monitor would have displayed those symptoms consistently from first use.
    • by r00t ( 33219 ) on Tuesday February 14, 2006 @11:31PM (#14721886) Journal
      Try your CRT on a monitor test [] and see how bad it really is.

      Eeeeew. You want to edit photos with that ???

      • That hurts my eyes (on an Optiquest Q95 CRT)
      • Eeew.

        You edit photos that consist of black and white lines???

        Unless your family members are all referees, that's the most absolutely fucking worthless tool with which to evaluate a display that I've ever. It has no semblence to any photographic editing task, and is designed to demonstrate (not "test") precisely two flaws inherent in CRT monitors design: Imprecise pixel placement, and limited bandwidth, while also demonstrating none of the LCDs flaws.

        Anyway: Your test looks fine at a perfectly reasonable
  • bad cable? (Score:5, Informative)

    by dnamaners ( 770001 ) on Tuesday February 14, 2006 @06:18PM (#14719852) Journal
    Sounds like the exact problem had with an old CTR, it when all green. In the end it turned out to be a shorted cable, if you bent it one way it would go normal again. A new cable fixed that. I bet your A.) are using a 25 pin sub-D cable and B.) its cable (or its plug) has gone bad. The fact that it "got better" for some time may indicate this. Check it out.
  • I have one (Score:2, Interesting)

    by Gyga ( 873992 )
    like this I think the cable is messed up try wiggling the cable to see if the connection is bad (colors will change when wigling). If it does I found placing on leg on the cable keeps it in place, you might be able to replace it though.
  • by awing0 ( 545366 ) <adam&badtech,org> on Tuesday February 14, 2006 @06:19PM (#14719871) Homepage

    It could also be your VGA card. I have seen VGA boards go bad in such manners that the make darkened streaks across the screen, off color to complete wrong or missing colors and artifacting/flickering picture. Monitors sometimes go bad in the exact same way! I've been fooled into thinking a display was bad before.

    Also, this is a very slight possibility, but your VGA cable might be bad. If the cable is crimpled or damaged, there may be cross talk among the signal wires. This usually leads to a ghosted image, but may cause color problems.

    So, I'd check your display out on a different PC, with a new cable just to rule out those issues before buying a costly replacement. The case is probably going to be that your display is just bad. Viewsonic isn't a great name in monitors, but then again no one makes a good display anymore.

    As a long shot, but Windows and Mac OS X support color profiles. You might be able to compensate with software depending on your video card. I'm pretty sure has some sort of color profile support, though I may be wrong on that point.

    • Color profiles for LCDs are very hard to set up. The response curve for an LCD is decidedly non-linear, and it can't be described by a CRT's black point/white point/gamma curve parameters. Plug the display into another computer to make sure it isn't the video card, replace the cable to make sure that's not going bad, and if neither fixes it, replace the screen.
  • Many options (Score:4, Informative)

    by dr00g911 ( 531736 ) on Tuesday February 14, 2006 @06:21PM (#14719881)
    Sounds to me like how my screen looks when the VGA cable gets knocked a little out of whack with the video card. It might be a short in the monitor cable as well.

    Don't think I've ever seen an LCD panel drift in color unless it was a cabling issue. CRTs, on the other hand, generally either drift to red or green as they die in my experience.

    There's lots of software-based gamma/color correction fixes that you can apply to the monitor depending on your OS. The 'advanced' display driver panel should have some color/gamma adjustments if you've got an nVidia or ATI card under Win, and there's a big ass "calibrate" button on your display preference pane on the Mac that'll let you get stuff back in whack.

    If you're running any Adobe apps under Win or Mac OS 9, there's the Adobe Gamma control panel -- which I personally used when I had an old CRT that decided to go pink and dark on me.

    When you start talking calibration hardware, on the other hand, you're starting to talk about stuff like the Gretag-Macbeth EyeOne series or a Spider, which are probably more pricey than the new LCD you've got your eye on.
    • CRTs, on the other hand, generally either drift to red or green as they die in my experience.

      Off-topic, but also watch out for random distortions. Had a 17" CRT that I used as a backup when I was home from school that started to have random distortions on boot, and sometimes in Windows. Thought it was just an issue with a wonky cable or possibly some form of interference. Well, started the box up one day, monitor kicks on, and as I'm about to log in, I hear a horrible sizzling/squealing noise. I ripped t

    • Thinkpad LCD panels are notorious for color drift, usually toward green.
  • I am inclined to agree with one of the other respondants that the issue is that your LCD is broken. When the backlight starts to die it tends to cause a red shift in the LCD. I have had a few of them do that. As they start to die the red shift will be apparent when the display is first turned on, then become more accurate as it warms up. But as it continues to die it will remain more and more red.

    But on the off chance that this isn't happening a good color corrector is Spyder2 PRO. At $250ish it may

  • You didn't say which OS you were using.

    If you're using Windows, I assume you checked the more advanced features offered by your video driver. If not, try going to the advanced properties for your display.

    If that doesn't work, I know Adobe has a color profiler tool that comes with Photoshop. (It may come with the free Elements version; I don't know.) It may or may not help.

    In any case, do what everyone else is suggesting, and check your video cable. If it's built-in to your display, you're SOL unless it's
    • No color profiler in Elements 3, at least...and I've heard enough negative about Elements 4 not to "upgrade" to it to find out if there's one included.
  • Found these both on digg...
    this one boasts making the dead pixels alive again.... []
    this one is for ghosting.... cd-ghost-remedy/ []
  • by RingDev ( 879105 ) on Tuesday February 14, 2006 @06:56PM (#14720215) Homepage Journal
    I'm going to go with the Cable issue theory. I have seen similar issues come from a crimped cable and they're not that expensive to replace. And on that note, mark up on cables is freaking insane. I put in a few years of retail sales (CompUSA) and I assure you, cost on that $60 belkin cable is under $15. Do yourself a favor and buy a cheap-o cable or a rebranded store version.

    • Another vote for the cable, I've seen it before and I'm sure I'll see it again. Just go DVI ;)
    • I've seen my share of crappy video cables. If you're doing analog 1280x1024 or better, you really need to have a cable with individually shielded R, G, B, and perhaps even H and V sync. The best cables have thin coax cables for those 5 lines inside the VGA cable. I only buy UltraSpec cables for VGA [] (and 13w3) and SCSI. It's worth the added cost. And where else can you get a video cable that's thicker than your thumb for $30? :)

      You haven't seen good CRT graphics until you've seen 2048 x 1536 driven by a Matr
      • Wow. OK, I got so wound up on my analog CRT vga cable rant that I forgot that this whole article is about LCD color correction...

        My rule of thumb is stick to DVI for LCD, period. With DVI you don't have to muck around with sync, phase, geometry, etc. It just works. Color correction is a must if you're doing any sort of print work, there are great calibrators available. Digital LCD has been great ever since the Silicon Graphics SGI 1600SW LCD monitor + ColorLock calibrator from way back in early 1999. Don't
  • red hue for black (Score:3, Insightful)

    by Mysteray ( 713473 ) on Tuesday February 14, 2006 @07:09PM (#14720318) Homepage
    Instead of showing real black, i'm now getting a red hue for black

    That's the symptom to focus on.

    Unfortunately, no externally-applied color correction can make your blacks blacker. Possibly gray instead of red, but you would lose serious amounts of contrast.

    Loose/broken internal/external cable/connector. Very common problem for all electronics, but usually on monitors it shows up as a problem with white tints rather than black. A broken signal would usually tend towards zero volts (darker).

    I would think it's probably not a backlight issue either because, again, you are complaining about black rather than white.

    Does your monitor have DVI and VGA inputs? Have you tried the other one?

    Does it have an on-screen display mode? Is that mode equally affected by the distortion?

    Have hope, it might be possible to repair without surface-mount component-level repair.

  • I had the same problem with one of my ViewSonic VP171b. After you have done the requisite trouble shooting (jiggling/swapping cables, swapping vid cards) you can call ViewSonic for help. I mailed mine to them, they fixed it for me, and they mailed it back to me. Took all of two weeks. I think I paid for shipping to them, but they paid for the return shipping.

    Good luck.
  • by Sycraft-fu ( 314770 ) on Tuesday February 14, 2006 @07:42PM (#14720565)
    There are devices that can help. I'm with most of the others in that it's likely damage, and check that out first. Cable, obviously first since it's cheap, but might be the backlight or actual LCD array too. Could also be a video card.

    At any rate, if you want something that will do colour correction, what you are after is called, unsupprisingly, a Colorimeter. Basically it's a little device you stick on your monitor that measures colour values from the monitor, helps you change settings, and then builds a mapping table for your video card.

    The good news is they work great. On a good monitor they will get you slightly better, more neutral colour and a good match to properly calibrated printers. On bad moniotrs they can take a horrible image and make it acceptable.

    The bad news is that they are expensive. Not super expensive, but enough that it'll put a dent in your wallet.

    If you decide to go this route, I recommend the Spyder 2 from ColorVision (aka Datacolor). While it doesn't get the best results on some monitors, it always gets good results on all monitors. Also has good, easy to use software. The normal Spyder 2 is like $150, the Studio version is $250. Both use the smae hardware sensor, the Studio version just has better software which lets you do things like multiple monitors with different profiles, custom colour temp and gamma targets, and so on.

    However, I more recommend this for doing the fine tuning of a good monitor, rather than fixing a bad one. For the price, you can pretty much get a new monitor, which is more worth while. It's only really worth it as a fix-it tool for like a large lab or something. If you have a ton of compuers with various old monitors that you can't necessiarly replace, they work well for getting the best out of them.
    • I'll put in a vote for the puck that I use - monaco optix xr (pro).

      it even will do dualhead (if each head has its own gfx card - OR each head has its own gfx engine).

      it will also do laptops (ie, things that don't have r/g/b settable parms in hardware).

      mine was $240 back in december. yes, expensive - but you buy it once and then keep your screen updated (yes, they do drift over time). I suppose you could even sell the service of doing one-time calibrations, although that may exceed what is intended by 'sit
  • Assuming that your panel isn't broken, I would suepct that you need to adjust your contrast setting. (And then adjust backlight brightness to suit it.)

    I've seen many LCD's, especially lower-costing ones, have terrible linearity, and the problem is exacerbated when you dial in a contrast setting that does not map the full range of input values to your display panel's output full range.

    Another thing you can do to test is to try run the monitor with the PC disconnected -- many monitors bring up a "the monito
  • by way2trivial ( 601132 ) on Tuesday February 14, 2006 @08:44PM (#14721027) Homepage Journal
    plugs into usb, color corrects your monitor, and bonus- if you leave it plugged in and pointing out, as the room gets lighter/darker it adjusts the screen acording to room lighting conditions.... Area=0&idArea=2&idProduct=103&idArticleType_Produc ts=0 []
    • note: this MAY be a dongle. you MIGHT need it connected at all times, for the profiling to work.

      still not clear, but some language in the company advertising indicates that you need to always have this connected - and not just to get ambient light, either.

      I have the monaco optix xr and I use it on XP (sigh). but since I use vnc viewer on XP (works really well as a viewer platform) - and then my vncserver runs on freebsd - I have color profiling on all apps that start on bsd (or linux or solaris or ...) an
  • by Lord Satri ( 609291 ) <alexandreleroux&gmail,com> on Tuesday February 14, 2006 @09:28PM (#14721250) Homepage Journal
    Any computer user would be **surprised** the difference is makes to calibrate your monitors (thus creating an ICC profile). It allows you to synchronize your monitors, scanners, printers, etc. It works better with macs, but also works with windows (I'm in the process of making it work with Debian).

    Read more here: tion_tools.htm [] l.cxsa?toolid=1086&num=37&fnd=nfound&refcode=cmmea sure&PID=11713 []

    and of course: []
  • Samsung SyncMaster 570s TFT, which turned very pink. Using the built-in controls, I adjusted the colors back to somewhat normal, but it happened again. After doing this a few times, I realized that the color levels for RG&B sometimes went from 0-100, and sometimes from 0-255. So the red was at 255 = 100% and G&B were at 100 == much less%.
    So, it's some kind of firmware problem, and it can't be updated. Set all color levels to 0, unplug it, shake it like an Etch-a-Sketch, try anything to make it forge
  • While this is unusual and I wouldn't say typical, it does pay to look around and determine if the monitor you got was the best for the money, or if you should have spent a little more money.

    Color calibration is important for those in the printing and graphics industry, but then, your talking about calibrating $1000 displays, ones designed and certified to offer highly accurate color display. There is a reason why those Apple displays are so pricey, they are certified for the graphics industry.

    Any sub $500
  • The fact that it worked when away from your room.... I'm assuming your in school since you mentioned going home for vacation...leads me to believe that there is an environmental factor in play.

    I'm surprised no one else has at least mentioned it.

    Anyways, try repositioning it somewhere else in the room. Try turning off any other electronics (unplug them) in the area... all except your PC and Monitor.

    I could be wrong but it's worth a try, rather than replacing it or sending it off to be 'fixed' and getting it
  • Something to keep in mind when you're troubleshooting something is not to make assumptions, if you are going to rule out a possibility, make sure the reason for doing so is based on solid, non-circular reasoning, logical and valid. Also keep in mind that several things in a computer work together to make something happen, so just because the monitor is where you first see the evidence that something is wrong, it doesn't necessarily mean that the monitor itself is the problem.

    In this case, if you have the e
  • As many other have suggested, try basic troubleshooting:
    - Does it look the same on another computer (try PC or laptop)
    - Does it change if you wiggle the cable? Can you replace the cable?
    - Does changing the monitor color setting affect it? (If you were using 6500k try 9700k; try shifting the red down)
    - Have you tried something like the Adobe gamma utility to adjust the settings?

    Best suggestion I can offer is when you buy your next LCD monitor...
    1) Make sure it's a Samsung
    2) Make sure you get a digita

...there can be no public or private virtue unless the foundation of action is the practice of truth. - George Jacob Holyoake