TCL C9K vs TCL C8L / QM8L

As we mentioned regarding black levels and contrast – the C9K can make a huge impression in synthetic tests. Our measurements showed that on a screen 10% filled with white, the television can achieve... 4000 nits of brightness! It sounds out of this world, but – and here's where the pattern unfortunately repeats – the numbers say one thing, and the practical experience says another. In real movie scenes, the situation looks different. In the best-case scenario, when light effects occupy a large part of the image and the local dimming algorithm doesn't have to ponder too much about what to do with thousands of zones, the effect is really quite good. At that point, the C9K can hit around 1500 nits, which delivers a pleasant, intense burst and can indeed leave a positive impression.

The problem arises with smaller elements – such as stars in the sky, the moon, or individual reflections. That's when the proverbial cat comes out of the bag: the algorithms are not yet refined, and brightness drops to as low as 400–500 nits. That's a huge difference from the potential 4000 nits we saw in lab tests. Why does this happen? Most likely, the television is trying to protect the black levels in this way and minimize the halo effect around bright objects. Unfortunately, this comes at the expense of detail – some details simply vanish, and the scene loses its nature.

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.

For colour tests, we once again reached for the Filmmaker mode – a new feature in TCL televisions for 2025. While the direction is a step in the right way, the execution leaves a lot to be desired. The white balance in SDR content turned out to be too warm – there was an excess of red. On the other hand, in HDR, it swung in the opposite direction: the image became excessively blue. The Colour Checker test revealed quite a few colour inaccuracies that were noticeable to the naked eye. An even bigger problem turned out to be what we mentioned above – brightness management. Regardless of whether we were watching SDR or HDR content, the image tended to wash out the entire scene, giving it an unnatural, almost grotesque character. Therefore, it’s hard to call this a "director's mode" – because no director has ever seen such an image.

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.

After calibration, we finally managed to tame the white balance – and it immediately translated into a more natural image. Colours finally started to look as they should, and the overall presentation was incomparably better than on the factory settings. In other words – it’s worth taking a moment to improve this, as the gain is really significant. The gamma responsible for brightness management also managed to be brought into order in SDR content, and the effect was more than satisfactory. Unfortunately, when we turned on HDR materials, the situation quickly became complicated. No matter how we set the local dimming, the television had a tendency to do what it liked with the image – either it overexposed everything or darkened the darkest parts too much. Just like we saw in the scene from the movie Billy Lynn. Colour-wise, the improvement after calibration makes a great impression, but brightness management in HDR remains the Achilles' heel of the C9K and presents a certain technological limitation.

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.

Digital image processing on the TCL C9K is rather average. The smooth tone transition feature seems to be present, but activating it practically changes nothing – colour bands are still visible, and it can unintentionally highlight elements we’d rather keep hidden, such as object textures. Fortunately, it doesn’t remove film grain, but that’s poor consolation given that the effects are still meagre. It’s therefore hard to recommend using this option.

On the other hand, image scaling presents itself much better. Lower quality materials look quite decent – characters and backgrounds are rendered clearly, although of course, with sources like 576p, the laws of physics cannot be fooled. Occasionally, there’s characteristic edge distortion of objects, but that’s the fault of the source itself, not the algorithm. A plus for not having issues with overscan – the image isn't artificially cropped or enlarged.

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.

Similar to the C8K, the C9K is also a really fast TV – both figuratively and literally. It features a 4K panel with a refresh rate of 144 Hz, and at lower resolutions, the panel can even ramp up to 288 Hz. Such speed translates into practice – while watching sports or playing games, the image looks very smooth and clear. Additionally, in movies, we get an extra motion smoother called Motion Clarity, which allows you to adjust the smoothness to your own preferences – from cinematic "judder" to almost theatrical smoothness.

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.

From a gaming perspective, the TCL C9K is a complete tool. It features two (out of four) full bandwidth 48 Gbps HDMI 2.1 ports, so all the key technologies work: VRR (Variable Refresh Rate) and ALLM (Auto Low Latency Mode). Additionally, the manufacturer has included a really intuitive Game Bar that allows you to quickly check the most important parameters and adjust settings without fumbling through menus. Also, TCL's policy is a plus – the TV isn’t afraid of any HDR formats, even in game mode. Whether it's HGiG or Dolby Vision for the Xbox Series S/X console – everything works as it should, giving the player plenty of freedom.

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.