TCL C7L vs TCL C8L / QM8L

TCL C7L is undoubtedly an extremely bright television. In synthetic tests on static images, it can achieve peak brightness levels of around 2800 nits. This is an absolutely phenomenal result, considering the price range it falls into. Unfortunately, the tests with real film scenes are not as spectacular as the measurements of white squares. The brightness in actual HDR shots drops to around 1200 nits in the C7L model. This is still a very good result, as the vast majority of contemporary films are mastered at such a value. However, when small, pinpoint elements appear on the screen, the brightness of those details drastically drops – even to about 400 nits – which diminishes the HDR effect somewhat. The television does this intentionally to maintain a better level of black and prevent a huge glare of light. This is somewhat explainable, but it also shows that Mini LED technology is not completely uncompromising in this regard. As for the HDR effect itself – alongside brightness, colors are obviously key here. And these, thanks to the use of new, "super" quantum dots, are simply outstanding and among the best on the market. The television can achieve around 90% coverage of the ultra-wide color gamut BT.2020 and 99% of the DCI-P3 gamut, easily matching the best RGB MINI-LED screens. Best of all, the C7L can maintain such high color saturation regardless of the scene being displayed, which is often problematic in competing RGB Mini-LED televisions.

In terms of HDR, the TCL C8L turns out to be a hellishly bright television – and I mean literally. On a synthetic chart of 5%, our measuring equipment indicated a result exceeding 4500 nits. This is a result that is downright cosmic, considering that reference director monitors, 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 exactly. Dry synthetic tests are one thing, and real movie images are another. In real, varied scenes, the C8L achieves a peak of around 1600 nits. This is still a very good result, ensuring a very high level of HDR dynamics, but also clearly lower than what the manufacturer boasts in the specifications. The trouble starts with very small flashes of light – then brightness can drastically drop to around 600 nits. The algorithm tries at all costs to maintain deep black and minimize halo effect, but it does so at the expense of HDR impact. This is perfect evidence that laboratory charts rarely correspond to what we ultimately see on the screen.

Huge applause is due for color 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 true jaw-dropper is the measurement of the extremely demanding BT.2020 space. The C8L achieves as much as 90% in it, placing it alongside today's top screens that boast RGB backlighting. Importantly, unlike some screens with Micro/Mini RGB backlighting, this effect is stable regardless of the scene displayed. Of course, one must remember that content mastered for such a wide gamut in films or series is still a rarity. However, the mere fact that the panel has such a "color reserve" deserves immense admiration.

When it comes to colors straight out of the box, what's new in TCL TVs, including the C7L model, is the addition of a picture mode called Filmmaker Mode. That's significant because until now that mode wasn't available from this manufacturer at all. In theory, as the name suggests, the image in this setting is meant to represent the filmmaker's full intent. From our tests we can confirm that it's without a doubt the best built-in mode on this TV if you care about faithful color reproduction right out of the box. However, we wouldn't say it's perfect. Like most devices on the market, this C7L also had some factory issues. The white balance in Filmmaker Mode tended toward a slightly greenish-yellow tint, caused mainly by an excess of the green channel and a noticeable lack of blue. For the average viewer this won't be a drastic flaw, but if you care about perfect whites, natural skin tones, and getting the full potential out of the structure of these new "super" quantum dots, the TV really begs for professional calibration.

We tested the TCL C8L in the best factory picture mode available in this TV’s menu for image fidelity. That, of course, is Filmmaker Mode, which appeared in this brand’s software relatively recently (a year ago in the "K" series). Thanks to it, an average user can get a pretty good color reproduction straight out of the box, although it is certainly not a perfectly tuned mode. Looking at the factory white balance of our unit, both in SDR and HDR material, the red component was clearly lacking, which made the image noticeably cooler and caused a slight shift toward bluish-green tints. The issue of brightness management is also ambiguous, as we mentioned earlier. While for SDR content the gamma linearity is actually correct and holds steadily at the reference value of 2.4, in HDR things look much worse. Tracking the EOTF curve clearly shows the TV has a significantly boosted brightness across the range, which can make the final image overly bright and inconsistent with the creators’ intent, and that in a mode that by definition should avoid that. Of course, like every sample in our lab, this one also underwent professional calibration, and its results are shown below.

After a professional calibration we were able to greatly improve the out-of-the-box Filmmaker Mode. After our adjustments, errors in the ColorChecker test and across the wide color gamut fell below the threshold of human perception, that is below a value of 3, which is a very good result. The TCL C7L definitely benefits from this treatment in terms of color accuracy, and that's hard to argue with. A bit worse, however, is the issue of brightness management in HDR content after calibration. As I described earlier, even though we set this model up correctly, when you play real movie scenes on the TV it can manage its brightness in a rather peculiar way. It often brightens certain elements on the screen contrary to the creator's intent, which can be clearly seen on EOTF charts measured in particular films. Despite this flaw, or rather a specific quirk of this TV, you can't take away one thing: after calibration the C7L was able to reproduce colors accurately.

As you can see, the results of a professional calibration of the TCL C8L are really promising, thanks to the extensive adjustment tools the manufacturer put at our disposal in the menu. Above all, we were able to completely correct the white balance — we eliminated the red deficiency, so the image finally stopped drifting toward unwanted cool tones. After that adjustment, errors in the ColorChecker test fell to near-reference levels, regularly landing below a Delta E of 2, which is below the threshold of human perception.

If the test patterns look this 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 actual movie material (I recommend enabling the EOTF filter when watching movies), you can see that in most scenarios the TV still reacts to HDR metadata its own way. As a result, the picture can be slightly over-brightened and not faithful to the creators' intent, and it was precisely this lack of consistency with real films that cost the C8L a few points.

This point could, in a sense, be called the Achilles' heel of the C7L. Unfortunately, this TV uses an older MediaTek chipset, the Pentonic 700, which was never known for outstanding digital image processing. You can clearly see this in the operation of the gradual smoothing function, which is responsible for reducing jagged edges and removing digital noise. It simply performs very poorly; when set to low, its effectiveness is practically nonexistent. The only small plus is that the algorithm doesn't further degrade the image or forcefully blur details. Upscaling itself, meaning the scaling of lower-resolution content to 4K, performs a bit better. It's simply adequate and doesn't stand out compared with the competition. That said, there's no denying the C7L would gain a lot in this area if the manufacturer decided to use the newer Pentonic 800 processor, which is now appearing in an increasing number of competing models.

This year the C8 series and higher models received probably the biggest and most anticipated upgrade in TCL’s history, and it specifically concerns digital image processing. The C8L is the lowest-end model in the manufacturer's lineup to be equipped with the latest flagship chip, the MediaTek Pentonic 800 (listed in the menu as MT9655). Thanks to its processing power, the feature called "Gradual Smoothing" finally works as it should. The algorithm effectively eliminates unwanted posterization (ugly tonal transitions/color banding), 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 evaluating this element can be mostly 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 to the competition.

The TCL C7L uses a native 4K panel with a 144 Hz refresh rate, which, at lower resolutions when using a PC, can even reach up to 288 Hz. Those are obviously very high numbers and look impressive on paper, but in everyday use it's worth remembering that almost all dynamic content you play on this TV will still run at around a maximum of 120 Hz. To tame that motion, the TV's menu includes a motion smoothing system called "Motion Clarity." It offers several predefined modes, including a user mode that we strongly recommend setting manually using our tried-and-true guides on our YouTube channel. There are two key sliders available there. The first, "Blur Reduction," reduces smearing and improves sharpness in dynamic 60-fps material, such as sports broadcasts. The second slider, "Flicker Reduction," lets you add artificial frames to movies and TV series shot at cinematic 24 or 30 fps. This, of course, allows you to completely eliminate the annoying image judder during camera motion.

The TCL C8L is equipped with a fast panel that has a native 144 Hz refresh rate. That spec will be most appreciated by demanding PC gamers, while most users, who rely on consoles or TV broadcasts, will use a steady 120 Hz. It is at 120 Hz that motion processing algorithms handle image rendering for movies, series, and sports. In the TV’s menu you’ll find a "Motion Clarity" option that lets you adjust the motion smoothing to your preferences. The algorithms handle cinematic material at 24 or 30 frames per second (fps) as well as dynamic sports broadcasts at 50 or 60 fps, maintaining appropriate smoothness.

When it comes to gaming, the TCL C7L is simply an outstanding TV for gamers. Thanks to two full-bandwidth HDMI 2.1 ports at 48 Gbps, you get access to all the key features required by console owners and users of powerful PCs. It has a well-implemented ALLM mode with very low input lag and VRR frame-sync that works in an impressive range from 48 to 288 Hz. Importantly, unlike some competitors, TCL implemented the console HDR10 HGIG profile correctly and added support for Dolby Vision in games. Rounding out the package is a very well-designed player panel, the Game Bar, which even lets you edit its appearance and change the theme to perfectly match your console’s style. The only thing you can — and should — criticize is that the TV offers only two full HDMI 2.1 ports, while the other two are older HDMI 2.0. That creates a fairly significant logistical problem. Why? Because one of those fast ports also supports eARC (enhanced Audio Return Channel). In practice, that means if you connect a soundbar or a home theater system, you’ll only have one free HDMI 2.1 port left. If you have two consoles at home, or a console and a powerful PC, you’ll unfortunately have to give something up or constantly juggle cables at the back while trying to maintain convenient control of your audio system.

For gamers – especially for those with powerful PCs and several consoles at the same time – the TCL C8L is a true beast. It’s the first model in the manufacturer’s lineup equipped with four full HDMI 2.1 ports with a maximum bandwidth of 48 Gbps. This is directly thanks to the new Pentonic 800 processor we wrote about earlier. Additionally, the TV seamlessly supports virtually every gaming feature. It has 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. We’re also talking about standards like G-Sync or FreeSync from Nvidia and AMD. When it comes to image display standards, there are also no compromises: the C8L offers complete support for HDR formats in games, including gaming Dolby Vision and the HGiG profile. All of these features can be conveniently managed from a very readable game bar (Game Bar), which we can customize according to our preferences. From a purely gaming perspective, there really isn’t anything to complain about in the C8L – well, maybe aside from the previously mentioned slight ghosting. But other than that? It’s an unflawed machine for gamers.