Philips OLED820 vs TCL C8L / QM8L

When it comes to HDR quality, the Philips OLED820 uses the same class of WOLED panel that we find in its biggest competitors – LG C5 or Samsung S90F. This means we can count on truly solid performance. This year, mid-range OLED panels are capable of exceeding the threshold of a thousand nits, and the model tested reaches around 1300 nits in some films. This is an outstanding result that allows for an extremely precise depiction of the director's vision, as contemporary productions are mastered in such brightness ranges. Of course, there are situations where even the OLED820 has to compromise. Full-screen scenes flooded with white, like those in the movie The Meg, can drop brightness to 400–500 nits, which clearly weakens the effect. This is a characteristic of OLED technology that has not yet been fully eliminated. Despite this limitation, it is hard not to appreciate the HDR in this model – high luminance and wide coverage of the DCI-P3 color gamut at 99% make the picture simply look great.

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.

The color reproduction in the factory settings really surprised us, and positively so. The Philips OLED820, switched to Filmmaker mode, immediately showed that it was quite well tuned in terms of color. The white balance was relatively accurate, though with a slight lack in the blue hue, which sometimes gave the image a slightly yellowish tint. However, this is not a flaw that particularly interferes with everyday viewing. A larger problem arose with the brightness characteristic. The gamma chart clearly deviated from the ideal, with the line being below the expected values, causing the image to be overly brightened, and the colors looked as if they were covered with a light milky filter. This effect was also noticeable in tests using the Colour Checker pattern, where more pronounced errors appeared.

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 calibration, both the Filmmaker mode and the game mode gained quite a lot. A slight adjustment of the white balance and an improvement in brightness characteristics resulted in excellent outcomes for SDR content – the image looked almost perfect, natural and very close to the reference. In the case of HDR materials, the situation was similar; the colors looked stunning and it was hard to find anything to criticize. However, we noticed a certain feature that we had already pointed out when comparing scenes from the movie Billy Lynn. An analysis of the EOTF curve revealed that the television has a slight tendency to dim details in the blacks, which means that the darkest sections are not always displayed exactly as the director intended. Nevertheless, the effect after calibration is remarkable, and the OLED820 stands out as one of the more interesting screens in its class. It just needs a little bit of fine-tuning, and there's really nothing to be afraid of.

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.

Fortunately, the earlier effects of the aforementioned posterization can be quite effectively mitigated. The "distortion reduction" feature set to medium handles unwanted color banding, improving the smoothness of tonal transitions. It does happen, however, that it works a bit too aggressively and smooths out some details – such as minor skin imperfections of the actors – but despite this, it can be considered worth using without major compromises. The upscaling in the OLED820 also performs well. The test image with the model is exceptionally soft, sometimes even too much so, although this can be alleviated by slightly increasing the sharpness in the picture menu – it’s a matter of personal preference. The lack of overscan issues with very low-resolution content is also commendable, meaning we don't have to worry that the image will be unnecessarily cropped.

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.

Motion fluidity is an area where OLEDs always shine, and the Philips OLED820 confirms this rule. The panel itself offers a refresh rate of 144 Hz, which will mainly benefit PC gamers, but even with standard television sources or consoles, where 120 Hz is used, the motion is fast, sharp, and simultaneously smooth, without traces of ghosting. This is thanks to the outstanding response time between pixels, which ensures the image retains clarity in every dynamic scene. The manufacturer has also added its own smoothing feature called "Motion Style." In the menu, we find two sliders – the first, responsible for fluidity, allows us to adjust the amount of artificially added frames in movies. This way, we can choose a raw, cinematic character with a clearly visible film frame or a more theatrical image with smooth motion. The second slider is for reducing blurring, especially useful in sports broadcasts. Here, we definitely recommend setting it to the maximum value, as the effect is truly excellent.

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.

Philips OLED820 is one of the most complete televisions for gamers. It practically has everything you could expect: two HDMI 2.1 ports with full bandwidth of 48 Gbps (too bad there aren't four), variable refresh rate VRR, automatic game mode ALLM, support for Dolby Vision in games, and a good implementation of the HGiG mode. The television also handles lower resolutions at 120 Hz without any issues, so you can count on great flexibility when choosing different picture modes on the console. Philips also adds Game Bar – a panel that allows you to change picture modes, add a crosshair, or view parameters. Although it looks quite clunky and is less polished than that of the competition, it serves its purpose. In practice, therefore, the OLED820, besides having a full set of four HDMI 2.1 ports, offers almost everything a gamer might need.

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.