When shopping for a new TV, you may experience poor color uniformity on a black background, also known as the “dirty screen effect” or DSE for short. So what is causing it and is there any way to fix it?
What is the dirty screen effect?
Dirty screen effect refers to the uneven appearance of solid colors, especially gray, black, or white backgrounds on display panels. It can affect anything with thin, modern displays, from TVs and monitors to smartphones and laptops. The effect is named because, under the right conditions, it resembles a kind of clouding on the display, as if the screen needs cleaning.
You can find the dirty screen effect on your TV with a full screen solid color. Under normal viewing conditions, you may only notice this effect in very dark or very bright scenes. It may only be visible in very dark rooms. Sometimes motion like camera panning (especially on solid colors, like the green field of a sports game) can make the effect stand out.
@SamsungUK Can you tell me how this vertical banding/dirty screen effect defect falls within the framework of your product specs? ! I’m pretty sure you won’t be using these images to promote your 2021 QLED lineup. Image movement on my TV (eg camera pan) is even worse! pic.twitter.com/lmC9pQYFo2
— Matt Francomb (@FrancombeMatt) October 3, 2021
DSE primarily affects LED-illuminated LCD panels, but a similar effect to DSE may also be visible on OLED displays. On LCD screens, this is caused by manufacturing issues with the panel itself or by uneven backlighting. In some cases you may see a grid of LED backlights using full array local dimming.
On OLED, this effect is either indicative of a faulty panel or a banding often noticeable on near-black content. Taking pictures of the display with a smartphone will almost always exacerbate this effect compared to real-world viewing conditions.
You’ve probably heard the term “panel draw” used to describe the purchase of a new TV. If your unit is showing signs of DSE, the “good” news is that very few panels look perfect when examined on full-field gray, white, black, or even color slides.
What can you do for this?
Before you rush to test the uniformity of your TV panel, consider this: if you don’t see any difference under real-world viewing conditions, your panel is probably good enough. Many TV owners don’t notice a problem until they look for it, at which point they notice a defect or problem area that’s hard to ignore. The same goes for OLED units with stripes and dark spots.
If you absolutely must test every aspect of your TV, do it when you first buy it so you can file a warranty claim right away. In the case of OLED, you might be asked to “run” for a few hundred hours or run a pixel refresh cycle on it to alleviate the banding problem before your request is fulfilled.
You can’t reduce the appearance of DSE on the LCD since the problem is with the manufacturing. Sites like RTINGS test each group of phenomena and post their findings online, but differences can arise between different products of the same model, made in the same year, and in the same factory. It’s a panel lottery!
New TV Review: @samsung america Q900/Q900R 8k QLED. Excellent 8k TV with impressive picture quality. It has wide viewing angles, but a similar contrast ratio to the Sony Z9F. Unfortunately, a lot of dirty screen effects are noticeable. https://t.co/tWXsRRrTLq pic.twitter.com/ENlJq31qQz
— RTINGS.com (@rtingsdotcom) March 27, 2019
If your TV does show some DSE under test conditions or your OLED has visible banding, try to forget about it. If you don’t pay attention to it, you may find it easily overlooked or even not obvious when watching a movie, streaming a TV show, or playing a game.
If it really bothers you and your TV’s warranty has expired – well, always buy a new TV. Of course, you will try again in the group draw.
Buying a new TV?
If you want a new TV, be sure to read our modern TV buying guide (as well as our gaming TV buying guide). We’ve also created a buying guide for the best TVs you can buy.