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LCD Color Corrector?
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.)"
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.
https://www.eff.org/https-everywhere
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....)
Karnal
Sears has the tool you need right here.
This guy's the limit!
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.
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.
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.
I don't preview or spellcheck.
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 X.org has some sort of color profile support, though I may be wrong on that point.
Cthulhu Saves.
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.
But on the off chance that this isn't happening a good color corrector is Spyder2 PRO. At $250ish it may be worth buying a new monitor instead (and last I checked the competition was even more expensive), but if you're doing work that requires accurate color then it's a good investment. A lot of people doing digital photography have that kind of thing; find out who you know who is seriously into that kind of thing and ask them if they have one you could borrow.
jim frost
jimf@frostbytes.com
The ad for Whatever University forgot to end the comment.
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 under warranty. If it's not, try dropping in a replacement cable.
tasks(723) drafts(105) languages(484) examples(29106)
Found these both on digg...l cd-ghost-remedy/
this one boasts making the dead pixels alive again....
http://udpix.free.fr/
this one is for ghosting....
http://www.beginnercode.com/index.php/2005/11/16/
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.
-Rick
"Most people in the U.S. wouldn't know they live in a tyrannical state if it walked up and grabbed their junk." - MyFirs
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.
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.
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 monitor is fine, but your computer is not" test pattern.
You can also try bring up the monitor's OnScreenDisplay and look at the colors. If those images looks fine, the panel itself is probably okay, and the problem is either in the input section of the monitor (where it converts VGA back into the digital signals that go to the panel), or with the VGA output from your PC. If you monitor has DVI in, running with DVI will also help you isolate where the problem is.
Finally, if your video card has enhanced utilities to control the gamma on separate color channels, you can play with that.
Good luck.
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....
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http://www.pantone.com/products/products.asp?idSu
every day http://en.wikipedia.org/wiki/Special:Random
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).
a tion_tools.htmi l.cxsa?toolid=1086&num=37&fnd=nfound&refcode=cmmea sure&PID=11713
Read more here:
http://www.drycreekphoto.com/Learn/monitor_calibr
http://www.chromix.com/ColorGear/Shop/productdeta
and of course:
http://en.wikipedia.org/wiki/ICC_profile
Animoog.org
Eeeeew. You want to edit photos with that ???
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 forget its settings. Actually, try everything the OSD will let you. Finally unpinked itself.
On the bright side, I've been using it for two years since then, without it pinking out on me, UNTIL YESTERDAY!! Hitting auto-adjust worked that time.
The latest Slashdot meme.
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 LCD monitor doesn't fall into that category. While you may be able to get near accurate colors, spending too much time calibrating the display (or being too finicky about the accuracy) will just result in a head ache.
Sounds like either your LCD is defective, or that perhaps you set the color temperature without realizing it. If your color temperature (ViewMatch Color on Viewsonics) isn't set to 9300K, then your going to get a redder screen. If that isn't the problem, and brightness/contrast settings don't have an effect, return the monitor of get it serviced, it could be a problem with the backlighting.
Doing a quick search on Google for reviews of this monitor shows it to not have great image quality and middling overall appeal. It may be cheap, but it looks like you get what you pay for in this case.
I haven't thought of anything clever to put here, but then again most of you haven't either.
I'd be willing to bet that its not software. Somewhere in the connection to the actual LCD component, there is a bad connection. It could be the VGA or DVI cable, but it sounds to me more like one "bit" of the RGB level signal is stuck low, which means that at the point where it connected to a parallel connection to the LCD component via a ribbon cable, the connection is bad. If you dont mind risking your warranty I would open up the monitor, look for any flat ribbon cable connections, carefully undo them and redo them.
You might not be able to solve it this way as it could be the ribbon cable connector soldering to the PCB, which can be very fine pitch. You might do more harm if you pull on the ribbon cable or if you dont work out how to release it from the connectors, there is often a little latch. But most things can be fixed by taking them apart and putting them back together, I should know as a qualified electronics engineer with a lifetime of doing this sort of repair. The explanation for why it worked when it was moved was because its a loose connection, so ignore the guys that say its a backlight problem, its not.
Its a ribbon cable connection problem inside the monitor.
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 back only to have the same problem when it returns.
Many display devices are sensitive to external radiation.. high levels of electro-magneticism can distort the electron flow causing all sorts of funkiness.
A fool throws a stone into a well and a thousand sages can not remove 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 extra equipment, you might want to try and switch the LCD with another monitor which you know for sure is working fine and see if the same problem shows up. If the problem is there with the second monitor which you know works when plugged into another system, the monitor is probably not the problem. Keep in mind that if the problem doesn't show up in the second monitor that it doesn't rule out driver problems, different monitors use different drivers unless you leave them on the defaults, and even then if the monitor has different capabilities, the operating system might be using a different driver for it. This part of my comment is obviously targeted mainly towards Windows which will attempt to find the 'best' driver for a device with minimal interaction with the user.
The fact that the monitor worked fine when you took it home and plugged it into a different system (I'm assuming this is the case) suggests to me that it is more likely maybe the cord, a port, video drivers, other display software, video card, some outside influence on the LCD, or, worst case scenario, the port or controller on your motherboard which deals with the video card.
Hence, if you have an extra cord you can swap in, see if it makes a difference.
Download and install the latest video drivers for your hardware to make sure the drivers aren't the problem.
Do you have a video color or gamma correction program running? i.e. for a printer or graphics software (I know adobe has one, several printer manufacturers have their own). If so see what happens when you disable it, perhaps it's not configured correctly.
Did you change your video resolution? Some video cards will have unanticipated distortion when you change resolution, though it's usually with older video cards and also usually the brightness and contrast which are changed, not color hue, it's worth switching resolutions a couple times to make sure.
If it was a CRT I would tell you to make sure you didn't have magnets, speakers, or other unshielded electronics right next to it, but magnets don't seem to affect an LCD like they do a CRT. I don't know what prolonged exposure might do to them, but just putting a magnet up to an lcd usually won't distort the display like it will with a crt. Never the less, see what happens if you move your monitor to a different part of your desk, away from other electronics, the wall, power ports, again, nothing lost in trying and if it's environmental interference, it can be the hardest to pinpoint.
Even those with good senses of humor, honor, and saintly intentions must occasionally require the use of a strong shield
- 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 digital interface (DVI) and use a card with a DVI connection
Good luck.
That hurts my eyes (on an Optiquest Q95 CRT)
Terrorists can attack freedom, but only Congress can destroy it.
This must be a common problem as Sears is already out of stock on that one!
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 Matrox card and connected by an UltraSpec cable.
Moral: Don't buy the crappy, overpriced video cables sold at your local big box store. Don't buy the cheap garbage either.
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 waste your time with analog LCD.