LG OLED G4 vs TCL C8L / QM8L

LG G4 guarantees an incredibly vibrant HDR effect, placing the television firmly at the top of the rankings. The highest model in the manufacturer's 2024 portfolio, equipped with the second generation of microlens technology (MLA), has achieved a maximum brightness level of 1474 nits in real scenes. The only area where the product of the Korean manufacturer may fall short compared to LCD televisions with Mini LED backlighting is during a full-screen scene featuring a lot of white. If we were to disregard the latter scene, the average result would be even higher. It's also worth mentioning scenes with very fine details, where each one shone at full intensity, which is not as evident in non-OLED televisions. The combination of such brightness and wide coverage of the DCI-P3 color space ensures that HDR materials are more engaging than ever before.

When it comes to HDR, the TCL C8L turns out to be a hellishly bright television – and I mean that literally. On a synthetic test pattern of 5%, our measuring equipment indicated a result exceeding 4500 nits. That's an almost cosmic result, considering that reference director's monitors, which we often refer to in our materials, usually operate around 4000 nits. Does this mean the C8L breaks barriers and climbs to the technological peak of Mini-LED? Not quite. Dry synthetic tests are one thing, and real film images are another. In real, varied scenes, the C8L hits around 1600 nits at its peak. That's still a very good result, ensuring a very high level of HDR dynamics, but it's clearly lower than what the manufacturer boasts in the specifications. The trouble begins with very small bursts of light – then the brightness can drastically drop to around 600 nits. The algorithm does everything it can to maintain deep blacks and minimise halo effect, but it does so at the cost of HDR impact. This is ideal evidence that laboratory test patterns rarely correlate with what we ultimately see on the screen.

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

The best factory mode in terms of colour reproduction was "Filmmaker". This is the one we used during our tests. Let's check how its characteristics looked before the calibration process. Taking a closer look at the white balance first, we can notice a significant dominance of red and green colour. As a result, the image had a warm yellow tint. This is the kind of characteristic we usually observe in "Cinema", "Filmmaker", or similarly named modes. The effect of such a colour balance was clearly visible in both SDR and HDR content, which, after switching from "Standard" mode, was distinctly yellowed. Now let's move on to two graphs that are responsible for brightness characteristics, and consequently, image contrast. The first one (Gamma), representing materials with a standard colour palette, performed decently. For most of the time, the midtones and bright whites were represented very accurately, however, it noticeably lost the darkest details which blended into a black patch. On the other hand, HDR materials, represented by the EOTF curve graph, exhibited a significant drop in contrast due to a strong boost in brightness. There was also an issue with the colours themselves as seen on the "ColorChecker" graph since they were noticeably undersaturated.

We tested the TCL C8L in the best factory mode available in the TV's menu for picture fidelity. I’m of course talking about Filmmaker Mode, which was introduced into this brand’s software relatively recently (a year ago in the K series). Thanks to it, the average user can get pretty good colour reproduction straight out of the box, although it’s certainly not perfectly tuned. Looking at the factory white balance of our unit, in both SDR and HDR content, there was a clear lack of the red component, which made the picture noticeably cooler and slightly shifted towards bluish‑green hues. The issue of brightness management is also ambiguous, as we mentioned earlier. While in SDR content the linearity of the gamma parameter is really good and consistently holds the reference value of 2.4, things are much worse in HDR. Tracking the EOTF curve clearly shows the TV’s brightness is considerably boosted across the range, which can make the final image overly bright and inconsistent with the creators’ intent, and that is in a mode that by definition should avoid this. Of course, like every unit in our lab, this one was also subjected to professional calibration, and you can find the results below.

The manufacturer has been implementing extensive support for the calibration process in their LG televisions for many years. Therefore, we used 2- and 20-point grey scale adjustments along with an advanced CMS (Color Management System) and got to work. As you can see, thanks to the procedure carried out, each of the parameters has significantly improved. The use of tools has resulted in extremely beneficial effects, which include: studio colour reproduction, recovery of details in dark areas of the image, appropriate brightness characteristics, and proper colour saturation. Thus, we have maximised our approach to the reference image, or the one that the film director saw on the preview monitor. It is worth noting that the LG G4 televisions are the only ones that allow for even deeper intervention in image quality due to the capability to calibrate with 3D LUT matrices. However, this solution is recommended only for post-production or graphic studios.

As you can see, the results of a professional calibration of the TCL C8L are genuinely promising, thanks to the extensive adjustment tools the manufacturer made available in the menu. Most importantly, we were able to fully correct the white balance, eliminating a lack of red so the image finally stopped drifting into unwanted, cool tones. After this step, errors in the ColorChecker test fell to near-reference values, regularly sitting below a Delta E threshold of 2, which is under the level noticeable to the human eye.

Since the test patterns look so perfect, you might ask: why then the lower final score in this category? The answer lies in the brightness management discussed earlier. Although the menu includes sliders that let you precisely straighten the EOTF curve on synthetic signals, when confronted with real film material (I recommend turning the EOTF filter on 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 image can be a touch too bright and not in line with the creators' intent, and it was precisely for this lack of repeatability with real-world films that we had to dock the C8L a few points.

The tested television did not perform well with content rich in tonal transitions, resulting in a strong posterisation effect. However, there is a partial remedy for this ailment. The manufacturer has equipped the LG G4 with a smoothing system called "Gentle Gradation," which we can apply at three levels: Low, Medium, and High. Each of these options guarantees quite high smoothing effectiveness on bright colours, though low on darker ones. We recommend primarily using the first one due to the fact that the other two interfere with directorial intentions, removing film grain.

When watching lower-quality content, the efficiency of the television during upscaling is extremely important. The image from the tested television is sharp and clear. However, attention should be paid to the jagged edges of fine details and minor issues around characters, such as the creation of a halo effect, which occurs due to the sharpening imposed by the LG G4 even when the slider is set to the lowest value, which is 0. It is worth noting that this is a change in relation to the LG G3, which did not impose such strong image sharpening, even when the appropriate slider was set to position 0.

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's to do with digital image processing. The C8L is the entry-level model in the manufacturer's line-up to be fitted with the latest flagship MediaTek Pentonic 800 chipset (shown in the menu as MT9655). It is thanks to its processing power that the feature called "Gradual Smoothing" finally works the way it should. The algorithm effectively removes unwanted posterization (ugly tonal transitions / colour banding) from the picture, 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 judging this element can be purely academic, because the differences between today's TVs in this class are very subtle. The most important point is that TCL finally has nothing to be ashamed of compared with the competition.

The maximum refresh rate that we can set on the LG G4 is 144 Hz. Naturally, this is only possible by connecting the LG G4 to a very powerful PC. Otherwise, we will be operating at a maximum refresh rate of 120 Hz, which is recommended if we primarily want to watch sports or content with high motion dynamics. For those who require high fluidity of image, the manufacturer has implemented a multi-level motion smoother called "TrueMotion". It has been divided into two separate sliders that adjust the sharpness of moving images (De-Blur) and judder (De-Judder). Both sliders can be set in the range from 0 to 10, with each increment affecting the degree of smoothing, so everyone can find their sweet spot.

The LG OLED G4 panel features an average response time of 0.78 ms (which directly results from our measurements), allowing for an incredibly clear image, unattainable by LCD televisions, which have response times of even several milliseconds. This is clearly visible in the "UFO Test" images, showing the absence of any trailing blur behind the object. Furthermore, the LG OLED G4 test showed that the television offers the ability to precisely adjust motion smoothing functionality, allowing users to choose the ideal level of image interpolation. We particularly appreciated this during fast-paced action in video games, where the LG G4 performed exceptionally well, minimising any blurriness. Thanks to OLED technology, this model eliminates so-called ghosting, ensuring that the image remains sharp even in the most dynamic sports or movie scenes.

The TCL C8L is equipped with a fast panel with a native 144 Hz refresh rate. That spec will be most appreciated by demanding PC gamers, while most users, relying on consoles or TV broadcasts, will use a steady 120 Hz. And it is at 120 Hz that the motion-processing algorithms take care of image processing for films, series and sports. In the TV's menu you'll find a "Motion Clarity" option that lets you customise the motion smoothing to your preferences. The algorithms handle both cinematic productions at 24 or 30 frames per second and fast-paced sports broadcasts at 50 or 60 frames per second, maintaining the right level of smoothness.

The LG G4 television supports all features that make up the HDMI 2.1 standard. During testing, each feature activated without any issues, which allows us to consider the television as designed for gaming. Its performance will certainly be appreciated by both console users and those connecting the LG G4 to a computer. It’s also worth mentioning the proper implementation of the HGIG (HDR Gaming Interest Group) mode, which ensures that games mastered to brightness levels beyond the maximum luminance of the LG G4 will correctly map tones, keeping the game image true to the original.

A nice touch is the presence of a special GameBar that we can bring up at any moment to check game parameters, but most importantly, to change them quickly. More importantly, turning on VRR technology does not degrade contrast, which is often a problem in televisions with local dimming or Mini LED backlighting. Of course, this is thanks to the OLED panel itself, characterised by pixel self-emissiveness. As a journalistic note, we will only mention a slight grey flicker, which, however, is somewhat normal when VRR is enabled.

In summary, the LG G4, like practically all OLED televisions, is an ideal product for all kinds of gaming and online competitions. With full HDMI 2.1 ports with a complete bandwidth of 48 Gbit, features such as VRR, ALLM, G-Sync, FreeSync, or HDR Dolby Vision gameplay will bring a lot of joy.

For gamers – especially for owners of powerful PCs and multiple consoles simultaneously – the TCL C8L is a true beast. This is the first model in this manufacturer's lineup that is equipped with four full HDMI 2.1 ports with a maximum bandwidth of 48 Gbps. This is directly due to the use of the new Pentonic 800 processor, which we've mentioned before. Additionally, the TV seamlessly supports practically every gaming feature. It has an automatic game mode (ALLM) that reduces latency to minimal levels, as well as full variable refresh rate (VRR) operating in an impressive range of up to 288 Hz. It also supports standards such as G-Sync and FreeSync from Nvidia and AMD. When it comes to image display standards, there are no compromises either: the C8L offers complete support for HDR formats in gaming, including gaming Dolby Vision and the HGiG profile. We can conveniently manage all these features from a very readable gamer bar (Game Bar), which we can customise according to our own preferences. From a purely gaming perspective, the C8L really has no flaws – well, maybe apart from the previously mentioned slight ghosting. But other than that? It’s a no-nonsense machine for gamers.