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LCD Monitor Gradiant Issues

Last response: in Graphics & Displays
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July 27, 2010 9:59:44 AM

I recently purchased a Asus VH242H LCD monitor. It has been working fine so far, except for one annoyance. On videos or games with gradients on a black background (words that pop out, fades, etc.) I notice clearly defined borders and blockiness around the gradient. It does not smoothly transition into the black background and is almost as though the monitor can not display enough colors to fully display the gradient (it looks kind of 16-bit colorish).

Are there any settings changes that I can make to fix this issue? Here is a screenshot of the type of image that makes my monitor mess up. On my monitor (when viewed at full resolution), the lighter parts of the gradient have a clearly defined and annoying border.

a c 359 U Graphics card
a c 195 C Monitor
July 27, 2010 3:25:20 PM

What you are describing is the limitation of nearly all monitors that uses TN panel technology. These types of panels are cheap to manufacture therefore monitors built using these panels are relatively in expensive; like your Asus. TN panel monitors probaby accounts for around 60% - 70% of LCD monitors sold to consumers because of the fact they are inexpensive.

The "inexpensiveness" comes at a price. TN panel technology is not capable of displaying 16.7m colors. Instead they can only truly display 256k colors. Thru the use of temporal dithering (flashing between two colors) they can imitate up to 16.7m colors.

I purchased the Asus VK246H for limited usage, basically connected to my HTPC to review processes from time to time. I probably use it about 3 hours per month now. Here's my review if you are interested:

http://www.tomshardware.com/forum/54250-3-asus-vk246h-r...

The VK246H also uses a TN panel and I have noticed some display issues similar to what you have describe; most notably in Batman: The Dark Knight (DVD version). In the scene where the hospital was blown up by the Joker, the black smoke was highly pixelated (blocky) and reveals on of the weaknesses of TN panel tech.

There are other panel techs around which does not have this "defect", but they are generally more expensive to manufacture. They are S-PVA, P-MVA and the various types of IPS panels; IPS being amongst the most expensive. When watching The Dark Knight on my other two LCD monitors and HDTV (all of which use IPS panels) I do not notice the pixelation issue.

However, gradient issues are not limited only to TN panels. For example, I believe I've read a couple that a few owners of the Dell U2410 has some minor gradient issues; it uses an IPS panel, not a TN panel. But that's just a few owners, not all owners.


At this point you have two options:

1. Live with it because there is nothing you can do to get rid of the issue. Not even driver updates.

2. Buy another LCD monitor that does not use TN panels.
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July 27, 2010 10:25:27 PM

Thanks for your detailed reply. One of the reasons that I am especially curious is because my old monitor (a ViewSonic VA1912wb) didn't seem to have this issue until the very end of its life. Now that the issue seems to have followed me to a new monitor, I am worried that my video card may be having issues.

Still, I am aware that TN technology has its issues. Any color tweaks to make the issue less obvious?
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a c 359 U Graphics card
a c 195 C Monitor
July 27, 2010 11:49:38 PM

Looks like you did a Print Screen to get that image. You need to take a picture of your LCD screen with a camera to show everyone the gradient issue you are having.

"PrtScrn" merely captures what the video card is displaying. Say for example you have a black and white LCD monitor that is only capable of displaying shades of gray, you do a "PrtScrn" an post it on the web, that image will be in color.
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August 2, 2010 4:03:06 AM

Sorry for taking so long to respond.

This is a PrtScn of the image being displayed:


Here are four pictures of the monitor displaying the above screenshot:






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a c 359 U Graphics card
a c 195 C Monitor
August 2, 2010 5:19:14 AM

Yep. I would have to say it is the result of your monitor being built around a TN panel.

Which Star Wars movie / game is that?

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August 2, 2010 6:04:51 AM

It is a trailer for Star Wars: The Old Republic. It has to stretch to fill the screen, which exacerbates the issue somewhat.

So there is no chance that it is the video card? Are all TN panels this bad?
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Best solution

a c 359 U Graphics card
a c 195 C Monitor
August 2, 2010 1:27:59 PM

There is nothing you can do about it short of replacing your LCD monitor. I looked one of the trailers for Star Wars: TOR on a monitor with an IPS panel (NEC LCD2690WUXi) and one with a TN panel (Asus VK246H). I can definitely say it is an issue with TN panels in general.

All TN panels uses some form of dithering to create around 16m colors. TN panels can only create 256k colors by itself. Through a process called dithering those colors are blended together to make up the rest of the colors. The gradients or color banding is one side effect of this process.

You need to purchase a monitor built around a S-PVA, P-MVA or IPS panel to get rid of that issue.
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August 2, 2010 10:58:19 PM

Best answer selected by zapas.
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August 2, 2010 10:59:18 PM

jaguarskx said:
There is nothing you can do about it short of replacing your LCD monitor. I looked one of the trailers for Star Wars: TOR on a monitor with an IPS panel (NEC LCD2690WUXi) and one with a TN panel (Asus VK246H). I can definitely say it is an issue with TN panels in general.

All TN panels uses some form of dithering to create around 16m colors. TN panels can only create 256k colors by itself. Through a process called dithering those colors are blended together to make up the rest of the colors. The gradients or color banding is one side effect of this process.

You need to purchase a monitor built around a S-PVA, P-MVA or IPS panel to get rid of that issue.

Thank you very much for your time and effort. I doubt they I can afford a better panel technology--what's the best that I can buy for $200?
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a c 359 U Graphics card
a c 195 C Monitor
August 3, 2010 12:56:44 AM

Nothing at $200. That's too low of a price point.

To get something that's close to the size of your current monitor, you need to save up approximately $350 for the Dell U2311H which uses a 23" e-IPS panel. I am not endorsing that particular monitor because I have not read any reviews of it; I'm just stating that's the best one given the size and your current budget.
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