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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
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.
And then jiggle the cable on the back. And make sure its firmly connected.
Occam's razor is the blind faith in the natural selection of least resistance and in universal oversimplification. -- EF
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.
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.
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).
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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 ???
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