TCL C6K vs Philips OLED820

TCL C6K is a moderately bright television that can showcase its full capabilities in the best movie conditions – the maximum brightness is around 600 nits. In scenes with large, intense light sources, the HDR effect can be truly satisfying, providing a sense of cinematic sparkle. However, it's important to remember that with local dimming management, there are situations where some elements become dimmed, and sometimes even barely visible. It is clear that there is a lack of proper optimization of the algorithms, although looking at the technical parameters in this price range, the build quality performs very well.

When it comes to HDR quality, the Philips OLED820 uses the same class of WOLED panel found in its biggest rivals – the LG C5 and the Samsung S90F. This means we can expect really solid results. This year, mid-range OLED panels can exceed the threshold of a thousand nits, and the tested model reaches around 1300 nits in some films. This is an outstanding result, allowing the director's vision to be conveyed with incredible precision, as this is the brightness range in which modern productions are mastered. Of course, there are situations where even the OLED820 has to compromise. Full-screen scenes flooded with white, like those in the film The Meg, can drop brightness to 400–500 nits, which clearly diminishes the effect. This is a characteristic of OLED technology that has not yet been fully eliminated. Despite this limitation, it's hard not to appreciate the HDR in this model – high luminance and a wide coverage of the DCI-P3 colour palette at 99% make the image look simply fantastic.

This year's TCL televisions have introduced the Filmmaker mode, and it must be said that it is definitely the best choice right out of the box. This is the mode we recommend for everyday viewing of movies and series. Unfortunately, as is often the case, the best does not mean perfect. In the case of SDR content, the image was too warm, as the red was quite prominent 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 an excess of blue. There is also the brightness characteristic, which at times led to overexposure. In practice, these issues combined resulted in quite noticeable errors in colour tests, which are hard to accept in a mode advertised as “by the creators”.

The colour reproduction in the factory settings really surprised us, and in a positive way. The Philips OLED820, switched to Filmmaker mode, immediately showed that it was quite well tuned in terms of colour. The white balance was relatively accurate, although there was a slight deficiency in the blue hue, which sometimes gave the image a slightly yellowish tint. However, this is not a drawback that particularly interferes with everyday viewing. A bigger problem arose with the brightness characteristics. The gamma chart clearly deviated from the ideal, as the line was below the expected values, causing the image to be excessively brightened, and the colours 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 adjustment, we were able to significantly reduce the C6K's tendency to distort colours, which resulted in a very good end result. After calibration, we won't 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, it's hard to have major objections – the picture looks really good, especially in older movies, TV shows, or material from YouTube. It performs significantly worse with HDR content. An analysis of the EOTF curve suggests that everything is fine, but in practice (EOTF in movies), the limitations of the construction become apparent. The television tends to excessively brighten the smallest fragments of the frame, and in other situations, it can overly dim the entire scene. The effect of calibration is therefore noticeable, and regarding colourimetry, the C6K has really gained a lot, but certain limitations resulting from local dimming and actually from its management by the C6K simply cannot be overlooked.

After calibration, both the Filmmaker mode and the gaming mode improved quite a bit. A slight adjustment of the white balance and enhancement of the brightness characteristics yielded excellent results with SDR content – the image looked nearly perfect, natural, and very close to the reference. For HDR material, the situation was similar; the colours looked fantastic, and it was hard to find fault with anything. However, we did notice a certain characteristic, which we had already pointed out when comparing scenes from the film Billy Lynn. The analysis of the EOTF curve showed that the TV has a slight tendency to dim details in the blacks, meaning that the darkest parts are not always displayed exactly as the director intended. Nevertheless, the effect after calibration is superb, and the OLED820 is emerging as one of the more interesting screens in its class. A little bit of fine-tuning is all that’s needed, and there’s really nothing to worry about.

TCL C6K performs quite well in terms of upscaling. Lower quality materials appear acceptable, and the absence of overscan issues means the image is displayed in full, without cropping. However, one cannot expect miracles – very low quality content won't come to life here, as the image processor has its limitations. On thin lines or details, there is characteristic tearing visible, which indicates a lack of advanced image enhancement algorithms. It is also a shame that the C6K lacks the function of smoothing tonal transitions – in older films or video materials, colour banding can be noticeable and may be distracting during longer viewing sessions.

Fortunately, the earlier effects of the mentioned posterisation can be quite effectively mitigated. The "distortion reduction" feature set to medium handles unwanted colour banding well, improving the smoothness of tonal transitions. It does sometimes work a bit too aggressively and smooths out some details – such as the minor imperfections of the actors’ skin – but despite that, 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 perhaps too much, although this can be remedied with a slight increase in sharpness in the picture menu – that's a matter of individual preference. The absence of overscan issues with very low-resolution content is also commendable, allowing us to not worry about the image being unnecessarily cropped.

TCL C6K uses a 144 Hz panel, which is a significant advantage in this price range. It's an important step forward in comparison to the previous model C655 PRO, which only offered 60 Hz in 4K. The difference is especially noticeable when watching sports or playing games – the ball, players, or fast action in the game are displayed more clearly and without losing detail. An interesting fact is the panel's ability to operate at 240 Hz, which the manufacturer doesn't mention in official materials. We will return to this topic when discussing the PC gaming mode.

TCL has also added a feature for movie watchers: "Motion Clarity," which allows users to adjust the image according to their preferences with two simple sliders. You can either keep the visible film frame or opt for a very smooth, almost theatrical effect. This way, everyone can find settings that match 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 TV sources or consoles, where it operates at 120 Hz, motion is fast, sharp, and simultaneously smooth, without any signs of smearing. This is thanks to the remarkable response time between pixels, which ensures the image maintains clarity in every dynamic scene. The manufacturer has also added their own smoothness enhancer called "Motion Style." In the menu, we find two sliders – the first, responsible for smoothness, allows for the adjustment of the number of artificially added frames in films. This way, we can choose a raw, cinematic character with clearly visible film frames or a more theatrical image with smooth motion. The second slider is for motion blur reduction, particularly 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 television that can confidently be called equipment designed for gamers. We have 4K at 144 Hz, VRR support, an automatic gaming mode (ALLM), and Dolby Vision Gaming. On top of that, there's a practical Game Bar, which is a panel with the most important settings handy – useful when we want to quickly change something during gameplay (e.g. screen ratio: Yes, you can!). Notably, it has a wide range of VRR, reaching up to 240 Hz. However, this option is mainly for PC gamers who drop below the native 4K resolution. In that case, the television can spread its wings and show additional smoothness, especially in fast e-sport titles. For consoles, we stick with the classic limit of 120 Hz, but the possibilities are still quite broad. The only slight drawback is some minor motion blur that can occasionally be seen in dynamic scenes. Other than that, the C6K offers everything gamers expect from a television.

The Philips OLED820 is one of the most comprehensive TVs for gamers. Onboard, we find practically everything one could expect: two HDMI 2.1 ports with full bandwidth of 48 Gbps (shame there aren't four), Variable Refresh Rate (VRR), Auto Low Latency Mode (ALLM), support for Dolby Vision in games, and a good implementation of the HGiG mode. The TV also handles lower resolutions at 120 Hz without issue, so you can count on great flexibility when choosing different picture modes on your console. Philips also adds a Game Bar – a panel that allows you to change picture modes, add a crosshair, or preview parameters. Although it looks a bit clunky and is less refined than its competitors, it gets the job done. In practice, therefore, the OLED820, in addition to a full set of four HDMI 2.1 connections, offers almost everything a gamer could need.