TCL C6K vs Philips OLED770

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.

The Philips OLED770 doesn't try to compete with the brightest OLEDs on the market, and it's actually hard to expect that, as it's the entry-level model in Philips' range for 2025. In our measurements, it reached a maximum of around 700 nits, which allows for enjoyment of HDR effects in scenes where light appears in spots – for instance, in the flash of headlights or a starry sky. In such moments, the picture can truly amaze. However, it's different when there are more bright elements on the screen. The TV, like many cheaper OLEDs, restricts luminance at that point, and the entire image noticeably dims. This was best seen in a scene from the movie The Meg, where the sun rises behind an oil platform – the brightness dropped to around 250 nits, which is almost three times less. The HDR effect remains pleasing to the eye, but it's worth being aware that this model performs best in scenes with less intense light. Fortunately, the OLED770 also has an ace up its sleeve – the coverage of the DCI-P3 colour palette is as high as 99%, so colours in movies and games are vibrant and very close to what the creator intended.

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 first measurements already show that the factory settings of the Philips OLED770 have a lot to improve, even in Filmmaker mode. The white balance chart clearly indicates a lack of blue, giving the image a slightly yellowish tint. In practice, white is not snow-like, but leans towards warmer hues – which some may even find appealing, but from a precision standpoint, this is a deviation from the norm. The gamma, on the other hand, tends to be on the darker side – the average value is around 2.6 instead of the reference 2.4. In mid-tones, the image appears muted and more saturated, which can look too "cinematic" but detracts a bit from the naturalness. However, the most significant issues are visible in colour reproduction. The average error is relatively high, and some colours – particularly shades of grey – deviate significantly from what should be seen. In everyday viewing, this means that sometimes colours may look less natural than we would wish.

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.

Philips OLED770 had shown signs from the start that it harboured significant potential, but it was hard to fully appreciate this in its factory settings. The image was often too warm, and some colours appeared as if they had lost their naturalness along the way. Calibration revealed that this television was very amenable to work – it responded to every adjustment and almost immediately unveiled another layer of its capabilities. The white balance was set in both SDR and HDR so that the yellowish haze disappeared and a neutral, clear white emerged. Gamma stabilised closer to perfection, which helped restore the naturalness of mid-tones, while shadows ceased to be artificially darkened, perhaps even with a slight brightening effect. The result was obvious... Movies are watched with greater ease; the image has cinematic depth without the feeling that something is overly darkened. However, the most interesting aspect was working on the colours. Factory errors were not dramatic, but slightly noticeable – skin tones could be too warm, and grey wasn’t always the shade we expected. After calibration, the error values dropped to around 2, and in many cases even below 1. This is a level that is definitely lower than the threshold of discernibility for the human eye. In other words, after correction, the colours finally “clicked” into place. Looking at the screen, we felt like the television had begun to speak with a full voice. Like an instrument that had finally been properly tuned.

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.

The problem of the previously mentioned colour connections can largely be mitigated thanks to the "distortion reduction" function, which is an algorithm for smoothing tonal transitions in Philips. It works best at a low level – effectively eliminating unwanted colour bands while not introducing strange artifacts or losing image detail. This is one of those features that is truly worth keeping on.

The issue of upscaling is somewhat less impressive. Images from lower resolution can be too soft, while in some parts the characteristic "jaggies" appear. The impression is that the algorithm is trying to reconcile two contradictory directions – smoothing and sharpening – and ultimately fails to find the golden mean. As a consolation, it's worth noting that the television does not have problems with overscan, meaning it does not cut off the edges of the image, which can sometimes happen in other competing models.

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.

The issue of the panel in the Philips OLED770 is not entirely straightforward. The manufacturer claims a 120 Hz panel, but our measurements showed that the screen can accept a 4K signal even at 144 Hz. This sounds like great news – because who wouldn't want an additional mode for PC gamers at this price? However, the reality turned out to be more complex. With 120 Hz content, the television behaves like most OLEDs – the image is absolutely clear, with no trace of blurring or smearing, ideal for both dynamic games and sports broadcasts. The problem only arises at 144 Hz. Unlike models with official support for this frequency, here we see the phenomenon of so-called frame skipping. This means that the television is unable to display all the frames – some of them are skipped, causing motion to lose smoothness and double outlines to appear on the screen. The effect resembles the operation of the BFI function, which Philips does not offer in this model anyway.

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.

If someone is looking for a TV for gaming, the Philips OLED770 is a candidate that's hard to overlook. The mere fact that this is an OLED gives it a great starting point – perfect blacks and infinite contrast make evening sessions in atmospheric games look like they've been taken straight out of a cinema. Added to that is the Ambilight system, which uses LEDs on the back of the TV to extend the image onto the wall behind the screen. The effect is such that even just playing FIFA can look like a small spectacle, and in horror games, the atmosphere becomes really thick. On the technical side, it's also quite decent. The Philips OLED770 supports variable refresh rate (VRR) up to 120 Hz, has an automatic mode for gamers (ALLM), and for those using an Xbox Series X, Dolby Vision support in games is also available. You just need to know that in this mode, the input lag is slightly higher than standard, although still at an acceptable level. As a bonus, we also get the 'Game Bar', which is a special tool strip for gamers. It's not the most conveniently designed solution, but it allows for a quick view of key parameters without exiting the game. Overall, this gives a picture of a TV that has all the most important gaming features on one hand, and on the other can add something unique – Ambilight. And it's this mix of technology and visual effect that makes the OLED770 one of the better screens for gaming in a home environment.