Samsung QN990F vs TCL C6KS / C69KS / Q6CS

Samsung QN990F is one of the bright televisions, and this is immediately apparent in tests. In measurements, it achieved around 1300 nits, which in practice allows you to enjoy films as their creators intended. Bright scenes have the right strength, lights shine, and the impression is truly cinematic. In standard test patterns, sequences number 1, 3, and 5 performed the best – there, brightness remained around 800-1000 nits, and the image looked very natural. In more difficult segments, it could dip to around 600 nits, but the level was still sufficient for details to be clearly visible. However, it should be added that with such highly contrasted shots, the halo effect returns – the same one we mentioned regarding blacks. Bright elements can leave a glow on dark backgrounds, and this is immediately noticeable. As we are dealing with a QLED, the colour palette is expanded, and the colours present themselves impressively. The problem is that with such a flagship model, we expected better numbers. 91% coverage of DCI-P3 and about 67% BT.2020 are results that can be considered solid but not outstanding. This gives an image that is vibrant and appealing; however, the competition in this and lower price ranges can show even more.

And what about HDR? Here the C6KS performs quite well and – as is becoming the theme of this review – just like in the C6K model. The maximum brightness generated by this television is around 600 nits. In bright scenes, this translates to a really solid, cinematic effect and generally, video materials look good here. However, it's important to keep in mind the specifics of the dimming algorithm in this model. When very small, bright points (e.g. stars) appear on a dark background, the television can quite significantly dim them. The goal is simple: to eliminate blooming and maintain the best possible black. It's a reasonable compromise. Most viewers will definitely appreciate deep, “true black” more than additional microscopic details, the display of which could cause the screen to appear greyed out. Such is the nature of local dimming technology in this price range, and one must be aware of this. It’s also worth noting that the TCL C69KS (C6KS) has an additional PFS coating, which is marketed under the QLED technology slogan. Thanks to this, the colours are saturated and vibrant – our measurements showed that the coverage of a wide colour gamut reaches as much as 92%.

We tested the QN990F in Filmmaker mode, which is the best out-of-the-box setting available. Right from the start, we noticed a few significant issues. The biggest problem was with white balance. Due to too little blue, as well as incorrect ratios between red and blue, the image—especially in scenes with a lot of white—appeared too yellow, and at times even orange. On the Color Checker palette, these errors didn't look dramatic as they hovered around a value of 4, but in everyday viewing, especially with strong whites, they were most noticeable. We also noticed problems with brightness management—the TV struggled to maintain details in the smallest parts of the image, mainly due to how it manages backlight zones. Fortunately, Samsung provides plenty of room for adjustment when it comes to setting corrections. We know that with proper calibration, much more can be extracted from this screen.

In contrast to the more expensive C6K model, in the tested C6KS we don't find an option in the menu labelled as Filmmaker Mode. Is this a reason to cry? Absolutely not. Our tests showed that in practice, in terms of colour reproduction, the lack of this specific label makes virtually no difference. The best available Film/Cinema mode here offers an almost identical picture profile to the aforementioned Filmmaker in the more expensive model. So we get a very similar image, just under a different name. Therefore, if you were wondering whether paying extra for the C6K would give you better colours – the answer is: no, in both cases the base is the same and requires slight adjustments.

After carrying out the calibration, we managed to bring the white balance into order and eliminate the earlier shortcomings in shades of blue. As a result, the picture no longer looked like it had a slight yellowish filter – the whites are cleaner, and the whole thing presents itself much more naturally. We also managed to tame the brightness characteristic in HDR content to some extent. The television now handles maintaining detail in blacks much better and does not lose them as much as before. However, when we look at the EOTF curve and how the QN990F reproduces brightness in films, it is evident that it still tends to accentuate details in dark areas more strongly. This is a characteristic feature of Mini-LED technology and, more specifically, how it is managed by the QN990F, which is practically impossible to eliminate completely. Despite this, after calibration, the picture looks significantly more natural, mainly due to the correct exposure of white light. The final effect is definitely more pleasant to the eye and closer to what we expect from a flagship television.

Thanks to the white balance adjustment, the C69KS's tendency to distort colours has been effectively limited, leading to a very good final effect. After calibration, we will no longer see excessive warmth in SDR scenes or overly cool tones in HDR. However, it is worth noting the brightness characteristic. In SDR content, there are hardly any objections – the image looks very good, especially in older films, TV shows, or YouTube materials. Evaluating the television's performance in HDR is much more difficult. Analysis of the EOTF curve suggests correct behaviour, but its practical variant shows certain limitations. The C69KS can overly brighten the smallest elements of the frame, while at other times it can dim the entire scene. Calibration has therefore brought clear benefits in terms of colour, but certain limitations resulting from local dimming and the way it is controlled by the C69KS cannot be avoided, which we also observed in the C6K test.

The QN990F deserves the highest praise for its upscaling capabilities. The processor responsible for 'lifting' classic TV to 8K resolution does a really decent job. Watching footage in 576p, we had no illusions that we would suddenly see a miraculous transformation like in an advertisement, where the image magically turns into crystal-clear 8K. Nevertheless, the final effect was surprisingly good; the picture looked clean and sharp. It's just a shame that the TV, like most Samsung models, has an overscan issue, which slightly cuts off the edges of the screen from the left side.

When it comes to image processing, Samsung offers a feature called "noise reduction," which in theory should improve tonal transitions in older materials, where they are usually more noticeable. Unfortunately, here we felt quite disappointed. The feature performs poorly – it struggles with unwanted banding and can even introduce its own artifacts. On the plus side, it’s worth noting that the TV doesn’t remove film grain when using this feature, but in practice, that’s a poor consolation when the noise reduction itself turns out to be practically useless.

The C69KS handles upscaling quite well. The tested 576p content looks surprisingly decent – a considerable amount of detail is preserved, and the algorithm adds a subtle ‘rounding’ effect to sharp edges, making the image appear more cohesive. However, it doesn't perform as well when it comes to smoothing tonal transitions. The television practically cannot improve them, leaving the image in a rather raw state. With older materials, this can be simply exhausting, as the lack of additional processing highlights all imperfections.

QN990F can easily be called one of the fastest TVs in the world. In 4K mode, it can display images at a frequency of up to 240 Hz, which until now was more associated with gaming monitors than with living room TVs. However, in everyday viewing, what's more important is how it handles an 8K signal at 120 Hz – and it performs very well here too. Motion remains smooth, and the TV handles even the most demanding content without breaking a sweat. Additionally, there's the motion smoother, or "Image Clarity." Thanks to this, you can adjust the picture to your preferences – leave it slightly cinematic with a bit of judder or switch to maximum smoothness, which works brilliantly for things like sports broadcasts.

C69KS offers a simplified motion enhancement panel in movies, allowing users to adjust the intensity of the effect using a slider. This makes it easy to tailor the smoothness to personal preferences. It also deserves credit for the ability to utilise higher refresh rates – even though the panel operates natively in 4K at 60 Hz, by lowering the resolution to 1440p, modes of 120 and 144 Hz can be enabled, on both consoles and PC. This sounds like great news, however, in practice, the image at these settings trails exceptionally badly. The effect is so pronounced that the overall experience simply appears mediocre and loses its appeal in everyday use.

It has to be said straightforwardly – the QN990F is one of those televisions that scream they were designed with gamers in mind. Samsung has been developing its gaming solutions for years, but here we have a true package. Sure, it lacks Dolby Vision support in games, which is a downside that will always come up in discussions. However, aside from that, the list of features is truly impressive. To start, we have the Game Bar – a handy menu that allows you to quickly check and change game-related settings. You can see things like VRR enabled, frame rate, or aspect ratio settings there. It's like a little “dashboard” so you don’t have to dig deep into the menu to fix something. Since the word VRR was mentioned: yes, variable refresh rate is present here and works flawlessly. Plus, there's ALLM, which automatically switches the television to game mode as soon as the console is turned on. These may seem like small details, but together they make using the QN990F simply convenient and hassle-free.

However, the greatest impression comes from the number of ports. Four wireless HDMI 2.1 ports as standard is already great news, as there's no need to choose whether to connect the console, the receiver, or maybe even the PC. There's comfortably enough room for everything here. And if we add another micro HDMI (which we recommend connecting directly to the console), hidden within the casing, then in practice we have five inputs in full 2.1 standard. Let’s also add support for high refresh rates – 120 Hz in 8K or even 240 Hz in 4K – and we get a television that not only keeps up with the new consoles but also feels ready for consoles that aren’t even out yet.

If we overlook the smudging and lack of native 4K at 120 Hz, the C69KS is impressive in how well it performs for gaming. You get everything you would expect from a gaming TV: Variable Refresh Rate (VRR), Auto Low Latency Mode (ALLM), Dolby Vision Gaming mode, and a consistently functioning HGiG. The TV can also operate at 120 or even 144 Hz at lower resolutions, making gameplay on console or PC smoother. Additionally, there's a clear Game Bar that allows you to quickly check key settings while gaming. As a result — despite a few limitations — the C69KS can be a genuinely successful screen for gamers.