TCL C9K vs Samsung S85F (WOLED)

As we mentioned with black and contrast – the C9K makes a huge impression in synthetic tests. Our measurements showed that on a screen 10% filled with white, the television is capable of squeezing out... 4000 nits of brightness! It sounds cosmic, but – and here unfortunately the pattern repeats – the numbers say one thing, and practice another. In real film scenes, the situation looks different. In the best case, when the light effects occupy a large part of the image and the local dimming algorithm doesn't have to think too hard about what to do with thousands of zones – the result is really quite good. At that point, the C9K can reach about 1500 nits, which provides a pleasant, intense flash and can indeed make a positive impression.

The problem begins with smaller elements – such as stars in the sky, the moon, or individual reflections. That's when the proverbial cat comes out of the bag: the algorithms are not yet refined, and brightness drops even to 400–500 nits. This is a huge difference compared to the potential of 4000 nits that we saw in laboratory tests. Why does this happen? Most likely, the television tries to protect the black and minimise the halo effect around bright objects. Unfortunately, this comes at the cost of details – some of the intricate details simply disappear, and the scene loses its nature.

For the majority of the time, let's say in 90% of film scenes, viewers will see virtually no difference between the versions of the S85F. When small, but very bright light points appear on the screen – a lantern in a dark alley, an explosion, the sun breaking through the clouds – this WOLED panel (similar to the smaller S85F) performs exceptionally well. Our measurements indicated a peak brightness of around 750 nits. We can state with full confidence: this is a great result that guarantees fantastic HDR effects. The problem arises in a very specific, uncomfortable situation for any OLED. We're talking about the moment when the entire screen must light up at full power brightly. Examples include a scene with a white background, a skiing scene, or our test sequences (5) from the film The Meg. And here, unfortunately, the results diverge significantly to the detriment of the variant with the WOLED panel. Our measurement equipment was able to register a maximum brightness of around 250 to 300 nits in such conditions. To be clear: the same model with a QD-OLED panel in the same test is nearly twice as bright. The second matter: colours. And here, we also have to be honest – QD-OLED has a structural advantage. Why? It's simple. QD-OLED generates colours from three components (red, green, and blue) and does not require an additional white subpixel. The WOLED panel we are testing here uses that white subpixel mainly to boost overall brightness. The effect is that QD-OLED is able to show a slightly wider colour palette and the colours are somewhat "purer". But to be clear: it's not that the colours on this WOLED panel are bad! On the contrary, they are really very good. The coverage of the DCI-P3 film palette at 97% and 71% for the broader BT.2020 palette is still high-end. We just need to honestly admit that this few percentage points of advantage in colour coverage lies with QD-OLED technology and may be noticeable in very specific moments.

For colour tests, we once again reached for the Filmmaker mode – a new feature in TCL televisions for 2025. And although the direction itself is a step in the right direction, the execution leaves much to be desired. The white balance in SDR content turned out to be too warm – there was an excess of red. Conversely, in HDR, it swung in the opposite direction: the image became excessively blue. The Colour Checker test revealed quite a few colour inaccuracies that were noticeable to the naked eye. An even bigger problem turned out to be what we mentioned above – managing brightness. Regardless of whether we were watching SDR or HDR content, the image had a tendency to blow out the entire scene, giving it an unnatural, almost grotesque character. Therefore, it is hard to call this a 'director’s mode' – because the director surely has never seen such an image.

When it comes to factory colour reproduction, our test sample in SDR mode suffered from a slight deficit of red and yellow colours. This resulted in a faint yellowish tint visible in shades of white. However, this is not the biggest problem with the S85F. As with the variant with a QD-OLED panel, the main issue with this model is the way it presents HDR content. When we look at the EOTF curve chart, it is easy to see that the television has quite significant problems with strong image clipping. Such behaviour causes the final image in many scenes to become very unnatural.

After calibration, we finally managed to tame the white balance – and it immediately translated into a more natural image. Colours finally started to look as they should, and the overall presentation was incomparably better than with the factory settings. In other words – it’s worth taking a moment to improve this, as the gain is really significant. The gamma responsible for managing brightness was also brought under control in SDR content, and the effect was more than satisfactory. Unfortunately, when we switched on the HDR material, the situation quickly became complicated. No matter how we set the local dimming, the television had a tendency to do what it pleased with the image – either overexposing the whole picture or dimming the darkest parts too much. Just like we saw in the scene from the film Billy Lynn. Colour-wise, the improvement after calibration makes a great impression, but managing brightness in HDR remains the Achilles' heel of the C9K and constitutes a technological limitation.

After conducting calibration in Filmmaker mode, we managed to eliminate most of the unwanted effects. In SDR content, the television performs excellently, with its colour reproduction errors not exceeding a value of 2, which is an outstanding result. HDR content looks slightly worse, though still very good. Although we were able to eliminate the significant unnaturalness of the image caused by the excessively high EOTF curve, the most discerning observers may notice that it is not perfectly aligned. It runs slightly below the reference curve, which would suggest that the S85F has minor difficulties in showcasing all the details in the image. We must emphasise here that it is very unlikely that the average viewer will notice any shortcomings in the image. The final effect after calibration is evaluated as exemplary.

The digital image processing in TCL C9K is rather mediocre. The tone transition smoothing feature is supposedly present, but activating it hardly makes any difference – colour banding is still visible, and it can inadvertently highlight elements we would prefer to hide, such as textures of objects. Fortunately, it does not remove film grain, but that's scant consolation considering the effects are still poor. Thus, it's hard to recommend using this option.

On the other hand, image scaling performs significantly better. Lower quality materials look quite decent – characters and backgrounds are represented clearly, although of course, with sources like 576p, the limitations of the physics cannot be disguised. Sometimes, there's characteristic aliasing of objects, but that's due to the source itself, not the algorithm. A plus for the fact that there are no overscan issues – the image is neither artificially cropped nor enlarged.

The processing of tonal transitions (gradients) in the S85F is at a high level. The television effectively handles posterisation (the "banding" effect of colours), even with heavily compressed content, e.g., from streaming services. However, using this feature requires a certain compromise. We noticed that the noise reduction algorithm is quite aggressive – even at the lowest setting, it can eliminate natural film grain, which for many viewers is part of the film's aesthetics. The "Standard" setting seems to be a happy medium, not causing a noticeable loss of important details, which is why we can recommend it. However, we advise against using the "High" level, which, in addition to noise, also removes desirable details such as texture or structure of objects on the screen.

The upscaling process of lower resolution content works very well in the S85F. The image is sharpened and clear. The only minor imperfection we managed to observe is occasional, subtle aliasing on the edges. The television still exhibits characteristics typical of this manufacturer, namely active "overscan" (slight image enlargement). It is worth keeping this in mind, especially when watching older content, as it may result in minimal clipping of the original frame.

Similar to the C8K, the C9K is also a really fast television – both figuratively and literally. On board, we have a 4K panel with a refresh rate of 144 Hz, and at lower resolutions, the panel can even ramp up to 288 Hz. Such speed translates into practice – while watching sports or playing games, the picture looks very smooth and clear. Additionally, in films, we get an extra motion smoothing feature called Motion Clarity, which allows you to adjust the smoothness to your own preferences – from the cinematic "stuttering" of frames to nearly theatrical smoothness.

S85F is a model with impressive speed. The use of a 120 Hz OLED panel ensures that dynamic scenes, both in games and during sports broadcasts, meet expectations: smoothly, sharply, and without loss of clarity. A key role here is played by the instant response time of the pixels, which is a natural advantage of OLED technology. Frame transitions are instantaneous, and the image remains clear even during the fastest camera movements. Moving objects, such as a ball on the pitch or a car in a chase scene, are clear and devoid of the characteristic motion blur associated with LCD panels (the so-called "ghosting").

For gaming, the TCL C9K is a complete tool. Here we have two (out of four) HDMI 2.1 ports with full bandwidth of 48 Gbps, so all the key technologies work: VRR (Variable Refresh Rate) and ALLM (Auto Low Latency Mode). Additionally, the manufacturer has included a really intuitive Game Bar, which allows you to quickly check the most important parameters and adjust settings without rummaging through the menu. Also worth noting is TCL's policy – the television does not shy away from any HDR formats, even in game mode. Whether it's HGiG or Dolby Vision for the Xbox Series S/X console – everything works as it should, giving the player a wide range of freedom.

The 85F has practically everything on board to become the dream screen for gaming. It features four full-fledged HDMI 2.1 ports with a bandwidth of 48 Gb/s, support for VRR (Variable Refresh Rate) and ALLM (Auto Low Latency Mode). Additionally, there's a super-detailed Game Bar, which clearly shows all the key parameters. However, the real gem is the Game Motion Plus feature. This motion smoother dedicated to games makes the animation more visually pleasing, while only slightly increasing input lag. This is a rare and well-functioning combination for which Samsung deserves great applause.

Now comes the moment where we must do a bit of complaining. The lack of Dolby Vision in Samsung TVs has become standard, so there's no point in hoping (unless something changes in the future). Unfortunately, it is much harder to explain the disappearance of support for HGiG after one of the software updates. HGiG (HDR Gaming Interest Group) is a key mode that allows for accurate reproduction of brightness in HDR games, according to the creators' intent. Without it, HDR calibration on the console becomes less precise, which can lead to an image that is too dark in the shadows or overly washed out in bright areas. Perhaps Samsung will fix this in the next update – we have high hopes for that. Because if HGiG returns, the S85F will become an almost perfect television for gamers.