TCL C6K vs Philips OLED820

TCL C6K is a moderately bright TV that can showcase its full potential under the best cinematic conditions – the maximum brightness is around 600 nits. In scenes with large, intense light sources, the HDR effect can be really satisfying, providing a sense of cinematic brilliance. However, it should be noted that when managing the backlighting zones, there are situations where some elements become dimmed and sometimes can even become barely visible. It is clear that there is a lack of proper algorithm optimization here, although looking at the technical parameters in this price range, the design itself performs very well.

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.

This year's TCL televisions feature a Filmmaker mode, and it must be admitted that it is definitely the best choice straight out of the box. This is the mode we recommend for everyday watching of movies and series. Unfortunately, as is often the case, the best doesn't mean perfect. In the case of SDR content, the image was too warm because the red was strongly emphasized in the white balance. On the other hand, with HDR content, we had the opposite impression – the image became cooler than it should have been due to excess blue. Additionally, the brightness characteristic sometimes led to highlights being blown out. In practice, this resulted in quite noticeable color test inaccuracies that are hard to accept in a mode advertised as "by the creators."

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.

Thanks to the white balance correction, it was possible to significantly reduce the C6K's tendency to distort colors, which resulted in a very good final outcome. After calibration, we will no longer observe the effect of excessive warming of scenes in SDR or overly cooling the image in HDR. However, it is worth taking a closer look at the brightness characteristics. In SDR content, there are few complaints – the image looks really good, especially in older movies, TV shows, or materials from YouTube. This is much worse for HDR content. Analysis of the EOTF curve suggests that everything is fine, but in practice (EOTF in films), the limitations of the construction become apparent. The TV tends to overly brighten the smallest parts of the frame, and in other situations, it can dim the entire scene too much. The effect of calibration is therefore evident, and in terms of color, the C6K has gained quite a lot, but certain limitations arising from local dimming and, in fact, its management by the C6K simply cannot be overcome.

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.

The TCL C6K performs quite well in terms of scaling. Lower quality materials look acceptable, and the lack of overscan issues means that the image is displayed in full, without cropping. However, one cannot expect miracles – content of very low quality will not gain new life here, as the image processor has its limitations. On thin lines or details, the characteristic tearing is visible, which reveals the absence of advanced image enhancement algorithms. It is also a pity that the C6K lacks the feature for smoothing tonal transitions – in older films or video materials, color banding can be noticeable and may be bothersome during long viewing sessions.

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.

TCL C6K features a 144 Hz panel, which is a significant advantage in this price range. This is an important step forward compared to the previous model C655 PRO, which offered only 60 Hz at 4K. The difference is especially noticeable when watching sports or playing games – the ball, athletes, or fast action in a game are displayed more clearly and without losing details. An interesting fact is also the ability of the panel to operate at 240 Hz, which the manufacturer does not mention in official materials. We will return to this topic when discussing the game mode for PC.

TCL also added a feature for movie watchers: "Motion Clarity," which allows you to adjust the image to your preferences using two simple sliders. You can keep the movie frame visible or opt for a very smooth, almost theatrical effect. This way, everyone can find settings tailored to their taste.

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 C6K is a TV that can confidently be called equipment designed for gamers. Here we have 4K at 144 Hz, VRR support, automatic game mode (ALLM), and Dolby Vision Gaming. Additionally, there's a practical Game Bar, a panel with the most important settings readily available – useful when we want to quickly change something during gameplay (e.g., screen aspect ratio: Yes, that’s possible!). The wide VRR range, reaching up to 240 Hz, deserves attention. However, this is mainly an option for PC gamers who drop below the native 4K resolution. Then the TV can spread its wings and show additional smoothness, especially in fast-paced e-sports titles. In the case of consoles, we stick to the classic limit of 120 Hz, but the possibilities are still quite broad. The only drawback is a slight ghosting that can sometimes be seen in dynamic scenes. Other than that, the C6K offers everything gamers expect from a TV.

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.