TCL C9K vs Samsung S85F (WOLED)

As we mentioned with black and contrast – the C9K can make 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 astronomical, but – and here, unfortunately, the pattern repeats – the numbers say one thing, and practice says another. In real movie scenes, the situation looks different. At best, when the light effects occupy a large part of the image and the local dimming algorithm does not have to think too hard about what to do with thousands of zones – the effect is really good. At that point, the C9K can reach around 1500 nits, which provides a pleasant, intense flash and can indeed make a positive impression.

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

For most of the time, let's say in 90% of film scenes, viewers won't see practically any difference between the S85F versions. When small but very strong light points appear on the screen – a lantern in a dark alley, a gunshot, the sun breaking through the clouds – this WOLED panel (like the smaller S85F) performs wonderfully. Our measurements showed peak brightness at around 750 nits. We can confidently state: this is an excellent 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 has to shine at full power brightly. Examples include a slide with a white background, a ski jump scene, or our test sequences (5) from the movie The Meg. And here, unfortunately, the results diverge quite significantly to the detriment of the WOLED panel variant. Our measurement equipment was able to measure a maximum of about 250 to 300 nits of brightness in such conditions. Just to be clear: the same model on a QD-OLED panel in the same test is almost twice as bright. The second issue: colors. And here we also have to be honest – QD-OLED has a design advantage. Why? It’s simple. QD-OLED creates colors from three components (red, green, and blue) and does not need an additional white subpixel. The WOLED panel we are testing uses this white subpixel mainly to boost overall brightness. The effect is that QD-OLED is able to show a slightly wider color palette, and the colors are a bit "cleaner." But let’s be clear: it’s not that the colors on this WOLED panel are bad! On the contrary, they are actually very good. Coverage of the DCI-P3 film palette at 97% and 71% for the wider BT.2020 palette is still a high standard. We just have to honestly admit that this few percent advantage in color coverage is on the side of QD-OLED technology and may be noticeable in very specific moments.

For color tests, as always, we reached for the Filmmaker mode – a new feature in TCL TVs for 2025. And while 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. On the other hand, in HDR, it went in the opposite direction: the image became excessively blue. The Colour Checker test revealed quite a few color errors that were noticeable to the naked eye. An even bigger problem turned out to be what we mentioned above – brightness management. Regardless of whether we were watching SDR or HDR content, the image tended to blow out the entire scene, giving it an unnatural, even grotesque character. It's hard to call this a "director-created" mode – because the director has certainly never seen such an image.

When it comes to factory color reproduction, our test sample in SDR mode suffered from a slight deficiency in red and yellow color. This resulted in a subtle yellowish tint visible in the shades of white. However, this is not the biggest problem with the S85F. Similar to the QD-OLED panel variant, the biggest issue with this model is the way it presents HDR content. When we look at the EOTF curve graph, it is easy to see that the television has quite significant problems with overly brightening the image. This causes the final picture 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. Colors finally started to look the way they should, and the overall presentation was incomparably better than in the factory settings. In other words – it’s worth taking a moment to improve this, as the gain is truly significant. The gamma responsible for managing brightness was also brought into order in SDR content, and the effect was more than satisfying. Unfortunately, when we turned on HDR materials, the situation quickly became complicated. No matter how we set the local dimming, the television had a tendency to do what it liked with the image – either it overexposed everything or dimmed the darkest parts too much. Exactly as we saw in the scene from the movie Billy Lynn. So, the color improvement after calibration makes a great impression, but brightness management in HDR remains the Achilles' heel of C9K and presents a certain technological limitation.

After calibrating in Filmmaker mode, we managed to eliminate most of the unwanted effects. In SDR content, the television performs exemplary, and its color reproduction errors do not exceed a value of 2, which is an excellent result. A bit worse, although still very good, are the HDR quality contents. While we were able to eliminate a significant unnaturalness in the image caused by too high a positioning of the 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 slight issues showing all the details in the image. We must point out right away that it is highly unlikely that an average viewer would notice any shortcomings in the image. The final effect after calibration is rated as exemplary.

Digital image processing in TCL C9K is quite mediocre. The tonal smoothing feature seems to be present, but turning it on practically changes nothing – color bands are still visible, and it can unintentionally highlight elements we would prefer to hide, such as textures of objects. Fortunately, it doesn’t remove film grain, but that’s small comfort since the effects are still poor. Therefore, it's hard to recommend using this option.

On the other hand, image scaling performs much better. Lower quality materials look quite decent – characters and backgrounds are presented clearly, although, of course, with sources at 576p, physics cannot be fooled. Sometimes, characteristic aliasing on objects appears, but that’s the fault of the source itself, not the algorithm. A plus for not having issues with overscan – the image is not artificially cropped or enlarged.

The processing of tonal transitions (gradients) in the S85F is at a high level. The television effectively handles posterization (the "stepping" effect of colors), even with heavily compressed materials, such as from streaming services. However, using this feature requires making 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 the golden mean, not causing visible loss of important details, so we can recommend it. However, we advise against using the "High" level, which removes not only noise but also desired details, such as texture or structure of objects on the screen.

The scaling (upscaling) process of lower resolution content works very well in the S85F. The image is sharp and clear. The only minor imperfection we observed is occasional, slight aliasing on the edges. The television also still exhibits characteristics typical of this manufacturer, such as active "overscan" (slight magnification of the image). This should be kept in mind, especially when watching older materials, as it may result in a minimal cropping of the original frame.

Like the C8K, the C9K is also a really fast television – both figuratively and literally. It features a 4K panel with a refresh rate of 144 Hz, and at lower resolutions, the display can even ramp up to 288 Hz. This speed translates into practice – when watching sports or playing games, the image looks very smooth and clear. Additionally, in films, we get an extra motion smoother called Motion Clarity, which allows us to adjust the fluidity to our own preferences – from the cinematic "judder" frame to almost theatrical smoothness.

The 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 instantaneous pixel response time, which is a natural advantage of OLED technology. Transitions between frames are instantaneous, and the image remains clear even during the fastest camera movements. Moving objects, like a ball on the field or a car in a chase scene, are clear and devoid of the characteristic motion blur typical of LCD panels (the so-called "tail").

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 key technologies work: VRR (variable refresh rate) and ALLM (automatic low latency mode). Additionally, the manufacturer added a really intuitive Game Bar, which allows you to quickly preview the most important parameters and adjust settings without digging through the menu. Also, TCL's policy is a plus – the TV is not afraid of 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 wide freedom.

85F has practically everything on board to become the ultimate screen for gaming. It features four full HDMI 2.1 ports with a bandwidth of 48 Gb/s, support for VRR (Variable Refresh Rate), and ALLM (Auto Low Latency Mode). Additionally, it includes a super-detailed Game Bar that clearly displays all key parameters. However, the true gem is the Game Motion Plus feature. This motion smoother dedicated to games makes animations more pleasant to the eyes while only slightly increasing input lag. This is a rare and well-functioning combination, deserving of high praise for Samsung.

And now comes the moment when we have to complain a bit. The absence of Dolby Vision in Samsung TVs has become standard, so there's no use hoping (unless something changes in the future). Unfortunately, it's much harder to explain the disappearance of support for HGiG after one of the software updates. HGiG (HDR Gaming Interest Group) is a crucial mode that allows for precise brightness representation in HDR games, according to the developers' intent. Without it, HDR calibration on the console becomes less precise, which can result in images that are too dark in the shadows or overly bright in the highlights. Perhaps Samsung will fix this in the next update – we have high hopes for that. Because if HGiG returns, S85F will become an almost perfect gaming TV.