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Tom's Guide
2 days ago
- Tom's Guide
Does your OLED TV look funny? Here are 5 common issues and how to diagnose them
OLED TVs aren't perfect. Despite their reputation of being some of the best TVs money can buy, OLED displays are susceptible to some odd visual quirks that range from minor blemishes like color banding to major issues like image retention. Having been in the TV-testing business for over a decade, I've seen everything from the earliest OLED models all the way up to the latest and best OLEDs on the market today and have needed to troubleshoot a fair number of them over the years. Here's a list of the strange oddities you might encounter with an OLED TV and whether or not they're worth worrying about. Though not a prevalent issue in recent years, some OLED TVs — particularly WOLED TVs used by LG and Sony — demonstrate minor color tinting when viewed a few feet away from a head-on position. Typically, the effect is most pronounced when the screen displays white a or near-white picture, like during the broadcast of a hockey game. The white portions of the picture will subtly shift into a pale pink or green, shifting as the viewer moves. As mentioned, it's been a few years since I've seen this issue, but folks with OLED TVs from around 2021 to 2023 might notice it from time to time. The cause of the tinting isn't one for concern. Fortunately, the cause of the tinting isn't one for concern, most likely having to do with variance in manufacturing. Based on reports across the web, the severity of the issue appears to be random, and I can personally attest that I've never witnessed a case so severe as to compromise the picture entirely. Get instant access to breaking news, the hottest reviews, great deals and helpful tips. While the above photo has been edited to illustrate the issue, it's plain to see that the OLED depicted is struggling to display a dark gray screen without saddling the left and right sides of the picture with a bold, pink column. Unfortunately, in my experience, this visual artifact tends to be more noticeable than the off-axis tint detailed above. This is because it tends to rear its head during any dark scene with low color saturation. In other words, a background wall doesn't need to be gray for the discoloration to appear. Black-and-white content will bring it out almost immediately. Much like the off-axis color tinting, this problem affects OLED TVs seemingly at random. However, not once have I seen the issue manifest on quantum dot-enhanced OLEDs like Samsung's excellent flagship, the S95D OLED TV. This leads me to believe that QD-OLEDs aren't as susceptible to the root cause. In my experience, QD-OLED TVs like the Samsung S95D tend to exhibit fewer visual quirks than TVs with WOLED panels. The S95D (one of our favorite OLEDs of its year) delivers an incredible picture and a sensational suite of features for gaming, streaming and beyond. To check your OLED TV for this issue, switch off your lights and, on your OLED, pull up this Dirty Screen Effect YouTube video uploaded by Sunil Raman. This short clip will start with a 100% black screen and gradually move up the grayscale until it displays 100% white. The dark gray-colored slides at 5% to 20% are particularly useful at coaxing out the pink tint. As far as I know, if you do discover pink-colored blotches, it can't be addressed outside of replacing the TV. Above is a close-up of a QD-OLED TV panel displaying a black-and-white checkerboard pattern. If you look along the edges of the black squares, you'll notice green- and magenta-colored rows of pixels. This is a result of QD-OLED's triangular subpixel structure, which places the green subpixel above red and blue. Fortunately, this minor, near-imperceptible color fringing is not a substantial mark against QD-OLED TVs. In general, you're most likely to notice this fringing when light-colored title cards or subtitles are on screen. Unless you intend on using a QD-OLED display as a monitor (or if you plan on regularly sitting very close to a QD-OLED TV), it's not a cause for concern. On rare occasions, I've seen OLED TVs arrive out of the box with vertical or horizontal banding across most or all of the screen. They usually manifest as straight lines of varying widths. Like the localized pink tint, this banding is most noticeable when large portions of the picture are white or gray. In my experience, OLED banding tends to work itself out after about five to ten hours of use. While it's frustrating to see these imperfections shortly after setting up a brand-new TV, I've got some good news: In my experience, OLED banding tends to work itself out after about five to ten hours of use. In the past, when I've reached out to LG about one of its TVs exhibiting this banding, a representative has recommended that I run the display's pixel refresher. Known as Pixel Cleaning on LG OLEDs (or Pixel Refresh on Samsung OLEDS), this process automatically adjusts the luminance of pixels depending on whether or not an unevenness is detected. Be warned, however: I would not manually run these pixel-cleaning features with any regularity. They can be aggressive over time — akin to scouring your display — and there's a good chance your OLED TV is already running a lighter, preventative version of the feature automatically when it's off. If none of these measures eliminates the TV's banding issue, I would brush up on the warranty and reach out to customer service. Burn-in is the only one of these issues that happens as a direct result of how an OLED TV is used. It describes the ghostly image of previously viewed content, now embedded within the display after many hours of use. Due to the organic nature of OLED displays, they're particularly susceptible to burn-in — or at least they were. Burn-in was something of an OLED boogeyman in the early days of the technology, but brands have built up plenty of defense against the issue in the years since. For instance, all major OLED-makers offer a pixel-shifting feature that occasionally (and subtly) moves the picture to ensure that each pixel is switching things up from time to time. The aforementioned pixel refreshing cycle remains an option, too, if you're noticing some image retention taking place. In general, the OLED TVs of today are far better equipped to prevent burn-in than earlier models. In general, the OLED TVs of today are far better equipped to prevent burn-in than earlier models. However, it still wouldn't hurt to give your TV a rest every now and then, particularly if you play games with static HUDs, or watch content with chyrons and/or tickers. If your OLED TV is exhibiting burn-in, it might be covered by the brand's standard warranty. LG, for instance, offers a one-year warranty on most of its OLED TVs which ought to cover burn-in, but the likelihood that you'll be dealing with OLED burn-in that soon is very, very low. Personally, I wouldn't let the prospect of burn-in stop me from shopping for an OLED TV. Nor would I let any of these issues dissuade me. The truth is, no TV is perfect — regardless of display technology. Due to the nature of their hardware, OLED TVs certainly need to be coddled a bit more relative to their LCD/LED counterparts, but those TVs come with their own potential quirks, too.
Tom's Guide
25-05-2025
- Entertainment
- Tom's Guide
What is the Dirty Screen Effect and how can you tell if your TV has it?
If you've spent enough time immersed in the world of TV — and I sure have — you might've heard about something called the Dirty Screen Effect, or DSE for short. Despite the name, the Dirty Screen Effect has nothing to do with busting out the microfiber towel and cleaning your TV screen (though you should probably do that soon). Given the amount of misunderstanding that surrounds the Dirty Screen Effect, I've put together a crash-course. It's DSE 101 — and class is officially in session. Depending on how you watch TV and what type of TV you're shopping for, however, you might want to familiarize yourself with DSE before buying for a new set. To put it simply, the Dirty Screen Effect describes hardware-level imperfections in an LCD/LED TV's display that are visually apparent under certain conditions. These visual blemishes typically manifest as blotchy shadows, darkened corners and vertical or horizontal banding. In some cases, there may be a lack of luminance alongside the edges of the picture. In other words, stuff just looks weird. Get instant access to breaking news, the hottest reviews, great deals and helpful tips. In most cases, DSE tends to be subtle, only calling attention to itself when large swaths of the picture are light in color and free of detail. A hockey game, for instance, is difficult for DSE to disguise itself behind. To keep things in perspective, it's worth noting that the Dirty Screen Effect will not be noticed by the vast majority of TV-owners — even under the punishing visual conditions of a televised hockey game. In rare, extra-severe cases, though, it'll rear its ugly head during every-day content. If you're not primed to spot the telltale signs, you may never see the Dirty Screen Effect. If you're not primed to spot the telltale signs, you may never see the Dirty Screen Effect or even think about it at all. You should count your blessings, as this is the sort of blissful ignorance I want after a decade of testing everything from the best TVs on the market to the worst. For the keen-sighted picture purists whose eyes are liable to twitch at the smallest of imperfections, the specter of Dirty Screen Effect looms large. The more you know about it, the more you fear it. Now that I've cursed you with this knowledge, let's talk about how we can put it to good use. I've got good news and bad news: The good news is that getting a sense of your TV's panel uniformity isn't that difficult. The bad news is that you can't do it until the TV is unboxed and set up in your home. If you want to see how your TV fares, you don't need a complicated array of testing equipment like what we use to test TVs at Tom's Guide. In fact, you can test the so-called dirtiness of your screen right now. Switch off your lights and, on your TV, pull up this Dirty Screen Effect YouTube video uploaded by Sunil Raman. This short clip will start with a 100% black screen and gradually move up the grayscale until it displays 100% white. If you look closely as your TV showcases the mid-tones, you might notice DSE. I had a few of my colleagues run this test themselves at home, and while I wouldn't call the example above severe, you can still get a sense of how DSE manifests on LED TVs. There is obvious vignetting in the corners, while shadowy, horizontal bands cover the left side and middle section of the picture. Before playing the video, make sure that your TV's ambient light sensor is disabled, and that you've taken steps to disable Eco Mode altogether (if available). Any high-quality video that showcases a single, light-colored image for an extended period of time is a decent candidate for demonstrating DSE. For clearest results, be sure that your TV is playing the video on the video's highest-quality setting. While certain assumptions can be made about panel uniformity across an individual TV series, DSE is ultimately a panel-by-panel phenomenon. In other words, we can assume that, as a mid-range TV with an above-average price tag, the TCL QM7K Mini-LED ought to offer a certain level of quality when it comes to panel uniformity. That said, we can't assume that the QM7K my colleague reviewed will demonstrate the same amount of DSE as any other QM7K. Key performance aspects will undoubtedly line up from one set to the next, but there's more variance when it comes to panel uniformity. You're more likely to encounter DSE in more-affordable, entry-level LED TVs. As much as bargain-hunters might not want to hear this, I must emphasize that you're more likely to encounter DSE in more-affordable, entry-level LED TVs. (For instance, I recently dealt with a fair amount of DSE on the Samsung DU7200, one of the cheapest TVs I've reviewed in the last year.) It still varies from one cheap set to another, but the likelihood of there being any amount of DSE is higher on TVs that were engineered and manufactured at a lower price point. Nevertheless, I've seen my fair share of mid-range and high-end LED TVs that were saddled with some amount of DSE, so it ultimately comes down to luck. If you're concerned about DSE to the extent that it might cut into the enjoyment of your new TV, I recommend using the method outlined above while you're still within the seller's return window. Keep in mind that an average amount of DSE won't be noticeable during most content, like basic cable, streaming shows and movies. No TV is perfect, and if you're not careful, you could find yourself dissatisfied with every TV you see. Typically, when we talk about DSE in TVs, we're describing visual blemishes brought on by hardware issues associated with LCD/LED TVs. Many of these issues revolve around the way LED backlighting is implemented at the manufacturing level. Because OLED TVs don't rely on a backlight — leveraging self-lit pixels instead — what we refer to as Dirty Screen Effect doesn't quite line up with what we see on OLEDs. That doesn't mean that OLEDs aren't susceptible to their own issues on a panel-to-panel a few occasions, I've seen some of the best OLED TVs arrive with vertical banding across most or all of the screen. Like LED-related DSE, this banding was most noticeable when large portions of the picture were white or gray. Fortunately, it's also been my experience that these visual artifacts can be treated by an OLED's built-in pixel refresh feature. Known as Pixel Cleaning on LG OLEDs (or Pixel Refresh on Samsung OLEDS), this process automatically adjusts the luminance of pixels depending on whether or not an unevenness is detected. I would not manually run these pixel-cleaning features with any regularity, however. They can be aggressive in their effect on your OLED TV over time, and there's a good chance your TV is already running a lighter, preventative version of the feature automatically when your TV is off. One OLED-related issue that was seemingly more prevalent just a few years ago was pink tinting, particularly along the sides of an OLED TV's picture. Like garden-variety DSE, this faint, sometimes-magenta-colored tint was most noticeable when neutral tones were displayed. This is a panel issue I was never successful at fixing with a pixel-cleaning session. Fortunately, in my experience, it seems as though newer OLED TVs (like the LG G4) aren't saddled with this issue as often as the OLEDs of years past. If you're worried about the Dirty Screen Effect taking the fun out of your next TV purchase, an OLED TV is probably your best bet. If you're worried about the Dirty Screen Effect taking the fun out of your next TV purchase, an OLED TV is probably your best bet, given their reputation for top-notch uniformity. If you'd prefer an LED TV but still want to minimize the randomness that comes with an LED panel lottery, I recommend starting with a mid-range model like the aforementioned TCL QM7K. I hate to put it into terms like this, but the higher-end the TV, the less likely it'll be that corners were cut during the manufacturing process.
