LG UT8100 (IPS) vs TCL C8L / QM8L

Unfortunately, the LG UT8100 television does not meet expectations in the HDR effect category. With a peak brightness of only 300 nits on the luminance chart, it is well below the required value to fully enjoy the HDR effects. In practice, the image resembles SDR quality more than true HDR, which is particularly evident in demanding high-contrast scenes. The coverage of the DCI-P3 colour palette is only 82%, further limiting the ability to present vibrant and rich colours. Instead of impressive visual experiences, we receive a muted and lacklustre image. For those looking for a television to fully utilise HDR content, the LG UT8100 model proves to be quite disappointing.

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 Filmmaker Mode in LG UT8100, although theoretically the best for watching films, has significant flaws. The biggest problem is the white balance – drops in blue colour cause a noticeable yellowing of the image, evident in both HD and 4K content. These errors are confirmed by the measurement results in the Colour Checker test, which indicate significant deviations in colour reproduction.

Regarding brightness characteristics, both HD and 4K content feature a substantial tonal boost. The gamma curve in both cases remains significantly below the reference value of 2.4, leading to excessive brightening of darker elements of the image. A similar issue is noticeable in the EOTF curve – for 4K content, the television struggles with properly managing brightness, which results in problems with screen brightness. This means that the factory settings of this model require significant adjustments to achieve better image quality.

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.

After calibrating the Filmmaker Mode, the gamma has been aligned to practically ideal, reference values, which has significantly improved the overall tonal characteristics of HD content. 4K HDR content also looks better, although certain issues are still visible at the extreme ends of the graph, where the curve deviates from perfection. The EOTF curve performs worse, as the television has difficulty maintaining appropriate brightness values. As a result, the image in some scenes may be overly bright or slightly dimmed, which is due to the very design of the device. Nevertheless, the calibration has brought considerable improvement, especially for HD content, where tonal balance and colour reproduction are now at a much higher level.

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.

The fluidity of tonal transitions is also correct, although the effect depends on the settings. The update has improved the performance of the smooth gradation function, smoothing transitions better than before, but it has introduced minor issues with detail loss, e.g. on textures.

The image scaling on LG UT8100 performs very well. The image looks decent, without significant issues with edge aliasing. Details are preserved at a satisfactory level, which makes lower resolution materials look truly solid on this television. This allows users to enjoy watching older content without noticeable flaws in quality.

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.

LG UT8100, equipped with a 60 Hz panel, is particularly suited for those watching films. The television offers the TruMotion system with de-judder effect adjustment, allowing you to customise the smoothness of the image – from more choppy to exceptionally smooth, resembling a soap opera effect, depending on the user's preferences.

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.

LG UT8100 offers basic features for gamers, such as ALLM and Game Bar, which makes access to settings easier. The television also supports HGiG, which improves image quality in HDR games. Unfortunately, the lack of support for Dolby Vision and VRR limits the capabilities of the device, as does the 60 Hz panel, which excludes support for 120 Hz resolution. This model is more suitable for less demanding gaming applications.

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.