TCL C8L / QM8L vs LG OLED B6

In terms of HDR, the TCL C8L turns out to be a hellishly bright television – quite literally. On a synthetic test pattern sized at 5%, our measurement equipment indicated a result exceeding 4500 nits. This is a truly astronomical result, considering that reference monitors used by directors, which we often refer to in our materials, typically operate around 4000 nits. Does this mean that the C8L breaks barriers and climbs to the technological peak of Mini-LED? Not quite. Dry synthetic tests are one thing, while real cinematic images are another. In real, varied scenes, the C8L peaks at around 1600 nits. This is still a very good result, ensuring a very high level of HDR dynamics, but it is also clearly lower than what the manufacturer boasts in the specifications. The problems begin with very small bursts of light – at that point, brightness can drastically drop to around 600 nits. The algorithm tries at all costs to maintain deep blacks and minimise the halo effect, but this comes at the expense of HDR impact. This is perfect evidence that laboratory test patterns rarely align with what we ultimately see on the screen.

However, huge praise is due for colour reproduction, thanks to the new generation of SQD (Super Quantum Dot) quantum dots. The DCI-P3 colour gamut coverage reaches 97%, but the truly jaw-dropping measurements come from the extremely demanding BT.2020 space. The C8L achieves an impressive 90% in this space, placing it alongside today's top screens equipped with RGB backlighting. Importantly, unlike some screens with Micro/Mini RGB backlighting, this effect is stable regardless of the scene displayed. Of course, it’s worth remembering that content mastered for such a wide gamut in films or series is still rare. However, the very fact that the panel has such a "colour reserve" deserves tremendous admiration.

The LG B6 is a moderately bright OLED. After calibration it reaches around 800 nits, roughly 200 nits more than last year’s B5. That’s down to the new, budget OLED SE panel from LG Display. In practice it simply gives a bit more headroom and makes HDR look fuller in many scenes than on last year’s lower‑end OLEDs. That does not mean the B6 has no limitations. In very bright shots, when a large part of the screen is strongly lit, brightness can fall below 400 nits. This behaviour is typical for OLED TVs, especially in this segment, and that’s where you see the biggest difference compared with more expensive models. Even so, we judge the B6’s results as genuinely solid. It’s still not a TV for breaking brightness records, but the HDR effect is strong enough that films truly feel like a step up from ordinary SDR. Colour gamut Using the OLED SE panel has had a slight impact on wide colour gamut coverage. Compared with last year’s model the results have fallen by a few percentage points. It covers roughly 96% of DCI‑P3 and about 71% of BT.2020. That doesn’t mean the colours on the LG B6 are weak. In most films and series they look lively, well saturated and simply pleasing to the eye. You only notice the difference in very bright, highly colourful scenes. Then colours lose some intensity compared with QD‑OLED panels. This stems from the WOLED panel structure. Besides red, green and blue subpixels it also uses a white subpixel, which helps to boost brightness. However, this comes at a price. At very high luminance some colour is effectively 'diluted' by the white light, so the saturation of certain colours can be slightly lower. In everyday use this isn’t a major issue, but in the most demanding scenes you can notice it.

We tested the TCL C8L in the best factory mode available in the TV’s menu for image fidelity. That’s of course Filmmaker Mode, which only arrived in this brand’s software relatively recently (a year ago in the "K" series). It allows the average user to achieve quite decent colour reproduction straight out of the box, though it is certainly not perfectly tuned. Looking at the unit’s out-of-the-box white balance — in both SDR and HDR material — the red component was clearly lacking, which made the image noticeably cooler and slightly shift towards blue‑green tints. The issue of brightness management also looks ambiguous, as we mentioned earlier. While the gamma linearity in SDR content is really good and stays steadily at the reference value of 2.4, the situation in HDR is much worse. Tracking the EOTF curve clearly shows the TV has a noticeably boosted brightness across the entire range, so the final image can be excessively bright and inconsistent with the creators’ intent, and this is in a mode that by definition should avoid that. Of course, as with every sample in our lab, we subjected this one to professional calibration, and you can find the results below.

We tested the LG B6 in Filmmaker Mode, the best picture setting available straight out of the box. ISF modes produce very similar results, but in our tests we always stick to Filmmaker Mode for better comparison with other TVs. Each of them is, in any case, a much better starting point than Vivid or Eco mode, where the picture is heavily boosted and noticeably less natural. On SDR material the factory settings perform really well. Colour errors are small, the gamma response is correct, and the picture during normal viewing looks natural and does not feel overly "pumped up". It's a bit worse with HDR. When such content is played you quickly see that the white balance hasn't been set perfectly. Too much blue and red gives the image a slightly pink tint. This is also confirmed by colour gamut measurements and the ColorChecker, where samples clearly shift in that direction. It's not a flaw that completely spoils the picture, but it is noticeable with HDR films. Therefore anyone who wants the most faithful image should consider calibration, which we cover further on in the review.

As you can see, the results of a professional calibration of the TCL C8L are truly promising, thanks to the comprehensive calibration controls the manufacturer has provided in the menu. Above all, we managed to fully correct the white balance, eliminating the red deficiency, so the image finally stopped drifting into unwanted cool tones. After that adjustment, the errors in the ColorChecker test fell to near-reference values, consistently sitting below a Delta E threshold of 2, i.e. below the visibility threshold for the human eye.

If test patterns look so perfect, you may ask us why the final score in this category is lower. The answer lies in the brightness management described earlier. Although the menu includes sliders that let you precisely straighten the EOTF curve on synthetic signals, when faced with real film material (I recommend enabling the EOTF filter when watching films), it becomes clear that the TV, in most scenarios, still responds to HDR metadata in its own way. As a result, the picture can be slightly over-bright and not faithful to the filmmakers' intent, and it is precisely for this lack of consistency with real films that we had to take a few points off the C8L's score.

During calibration, we concentrated mainly on HDR content, because that's where the factory settings needed the most correction. We did not, however, neglect SDR mode, which after adjustment was brought almost to perfection. Colours are very accurate, and brightness is controlled as it should be. The biggest improvement in HDR came from fixing the white balance. Removing the excess red and blue eliminated the pinkish tint, and the image became much more natural. Skin tones, whites and all colours that had previously shifted towards pink improved. After calibration most errors fell below a Delta E of 2–3, the threshold at which the average viewer stops noticing differences with the naked eye. So the LG B6 can deliver a very accurate picture, particularly for the manufacturer's entry-level OLED model.

This year the C8 series and the higher-end models have probably received the biggest and most eagerly awaited upgrade in TCL’s history, and it concerns digital picture processing. The C8L is the entry-level model in the manufacturer's line-up that has been equipped with the latest flagship chip MediaTek Pentonic 800 (listed in the menu as MT9655). It is thanks to its computing power that the feature called "Gradual Smoothing" finally works as it should. The algorithm effectively removes unwanted posterization (ugly tonal transitions / colour banding) from the image, doing so intelligently enough that it does not degrade the sharpness of other details.

The processor also handles upscaling lower-resolution content to 4K very well. Although assessing this element can be largely academic, because the differences between today’s TVs in this class are very subtle. The most important takeaway is that TCL finally has nothing to be ashamed of compared with the competition.

The LG B6 handles lower-quality material very well. This is largely thanks to effective digital image processing, which can mask some of the source’s imperfections without overly smoothing the whole scene. The "Smooth Gradation" function proves particularly useful. It noticeably reduces posterisation, especially in dark parts of the image. The safest choice remains the Low or Medium setting. The function still effectively smooths out unsightly tonal banding, but does not yet interfere too much with fine details. Purists can of course leave it switched off. Upscaling to 4K also performs very well. Full HD and 720p material retain a good amount of detail, and the image is neither overly sharpened nor heavily blurred. Some limitations only become apparent with very poor sources below 720p, where the smallest text and fine elements are not always perfectly sharp, but this applies to almost every other TV on the market.

The TCL C8L is equipped with a fast panel with a native refresh rate of 144 Hz. This specification will be most appreciated by demanding PC gamers, while most users, who rely on consoles or TV broadcasts, will make use of a stable 120 Hz. It is at 120 Hz that the motion-processing algorithms take care of image processing (in films, series and sports). In the TV menu you'll find a "Motion Clarity" tab that allows you to tailor the motion smoothing to your own preferences. The algorithms cope well with both cinematic productions at 24 or 30 frames per second and with fast-paced sports broadcasts at 50 or 60 frames per second, ensuring appropriate smoothness.

One of the biggest advantages of OLED panels is the very fast pixel response time. This keeps the picture sharp and free of the visible smearing often seen on LCD TVs. However, there is a downside. During slow camera pans motion can look choppier than on LCD screens, where some of that effect is naturally masked by the slower panel. Fortunately, on the LG B6 this can be easily mitigated using the TruMotion system. With the motion smoothing set correctly you can achieve smoother motion without giving the picture an exaggerated soap opera effect.

For gamers – and especially for owners of powerful PCs and several consoles simultaneously – the TCL C8L is a true monster. It is the first model in this manufacturer's lineup to feature as many as four full HDMI 2.1 ports with a maximum bandwidth of 48 Gbps. This is directly attributable to the use of the new Pentonic 800 processor, which we discussed earlier. Additionally, the television seamlessly supports practically every gaming feature. We have an automatic game mode (ALLM) that reduces latency to minimal levels, and full frame synchronization (VRR) operating in an impressive range of up to 288 Hz. There's also talk of standards such as G-Sync or FreeSync from Nvidia and AMD. When it comes to display standards, there are no compromises either: the C8L offers complete support for HDR formats in games, including gaming Dolby Vision and the HGiG profile. We can conveniently manage all of these features from a very readable player bar (Game Bar), which we can personalise to our own preferences. From a purely gaming perspective, there's really nothing to fault the C8L on – well, maybe aside from the previously mentioned slight blurring. But other than that? It's a no-nonsense machine for gamers.

LG OLED B6 has plenty to offer gamers; it’s simply a complete base for PS5, Xbox Series X/S or a capable PC. It has four full-size HDMI 2.1 ports with 48 Gbps bandwidth, so you can avoid irritating cable swapping when connecting several newer devices at once. It offers a full suite of synchronization technologies, from standard VRR to G-Sync and FreeSync. The screen synchronises the refresh rate seamlessly with the frame output from the console or graphics card. Of course it includes ALLM: the B6 automatically recognises when a game is running and immediately reduces latency to a minimum. HDR support is also excellent. The TV supports Dolby Vision, and a correctly implemented HGiG standard means that, after initial calibration in the console settings, the image won’t suffer from blown-out highlights or lost detail in bright areas. The cherry on the cake is the Game Bar. Instead of digging through the full menu during gameplay, a single click is enough to adjust shadow visibility, tweak selected parameters or simply check the current display mode. All of this makes the LG B6 an excellent choice for gamers.