Samsung QN990F vs TCL C6KS / C69KS / Q6CS

The Samsung QN990F belongs to the bright televisions and this is immediately evident in the tests. In measurements, it achieved around 1300 nits, which in practice allows you to enjoy movies as their creators intended. Bright scenes have the right impact, lights shine, and the feeling is truly cinematic. In standard test patterns, sequences number 1, 3, and 5 performed the best – there the brightness remained around 800-1000 nits, and the image looked very natural. In more challenging segments, it could drop to about 600 nits, but still the level remained sufficient for details to be well visible. However, it should be added that with such highly contrasted shots, the halo effect returns – the same one we mentioned regarding the blacks. Bright elements can leave a glow on dark backgrounds, and this is immediately noticeable. Since we are dealing with a QLED, the color palette is expanded and the colors look impressive. 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 results in a vibrant and attractive picture; however, competition in this and lower price segments can show even more.

And how does the issue of HDR look? Here the C6KS performs quite well and – as is becoming a recurring theme in this review – identically to 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, the video materials look good here. However, one must remember the specifics of the dimming algorithm in this model. When very small, bright points (e.g., stars) appear against a dark background, the television can dim them quite significantly. The goal is simple: to eliminate blooming and maintain the best possible black levels. It’s a reasonable compromise. Most viewers will definitely appreciate deep, “true black” more than additional micro-details that could cause grayness on the screen. Such is the nature of local dimming technology in this price range, and one must be aware of it. It’s also worth noting that the TCL C69KS (C6KS) has an additional PFS coating, which is marketed under the tagline of QLED technology. Thanks to this, the colors are saturated and vibrant – our measurements showed that the coverage of a wide color gamut reaches 92% here.

We tested the QN990F in Filmmaker mode, which is the best available right out of the box. Right from the start, we noticed several significant errors. The biggest issue was with white balance. Due to too little blue and also incorrect proportions 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 issues with brightness management – the television had difficulty maintaining details in the smallest parts of the image, mainly due to the way it controls the backlight zones. Fortunately, Samsung offers a lot of room for adjustment when it comes to setting corrections. We know that with proper calibration, you can definitely get a lot more out of this screen.

Unlike the more expensive C6K model, the tested C6KS does not have an option labeled Filmmaker Mode in the menu. Is this a reason to cry? Absolutely not. Our tests have shown that in practice, in terms of color reproduction, the absence of this specific label makes virtually no difference. The best available Film/Cinema mode here offers nearly identical picture characteristics to the aforementioned Filmmaker mode in the more expensive model. So we get a very similar image, just under a different name. So if you were wondering whether paying extra for the C6K gives you better colors – the answer is: no, in both cases the base is the same and requires slight adjustments.

After performing calibration, we managed to bring the white balance into order and eliminate the previous deficiencies in blue tones. As a result, the image no longer appeared as if it had a slightly yellowish filter – whites are cleaner, and the overall presentation looks much more natural. We also managed to some extent to tame the brightness characteristic in HDR content. The television now handles maintaining details in blacks significantly 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 emphasize details in dark scenes 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 completely eliminate. Nevertheless, after calibration, the image looks much more natural, primarily due to the correct exposure of white light. The final effect is definitely more pleasant to receive and closer to what we expect from a flagship television.

Thanks to the white balance adjustment, the tendency of the C69KS to distort colors has been effectively reduced, leading to a very good final effect. After calibration, we won't see excessive warmth in SDR scenes or overly cool tones in HDR. However, it's worth noting the brightness characteristic. In SDR content, there are hardly any objections – the image looks very good, especially in older films, television programs, or materials from YouTube. It is much more difficult to evaluate the performance of the television in HDR. Analysis of the EOTF curve suggests correct behavior, 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 color reproduction, but certain limitations arising from the operation of local dimming and the way it is controlled by the C69KS cannot be avoided, as we also saw in the C6K test.

The QN990F deserves the highest praise for its upscaling. The processor responsible for "pulling up" classic TV to 8K resolution performs quite well. While watching content in a 576p signal, we had no illusions that we would suddenly see a marketing-style miracle where the image magically transforms into crystal-clear 8K. Nevertheless, the final effect was surprisingly good; the image looked clean and clear. It's just unfortunate that the TV, like most Samsung models, has an overscan issue, which slightly cuts off the edges of the screen on the left side.

Regarding image processing, Samsung provides a feature called "noise reduction," which in theory should improve tonal transitions in older materials, where they are usually more noticeable. Unfortunately, we felt quite disappointed here. The feature works poorly – it struggles with unwanted bands and can even introduce its own artifacts. On the plus side, the TV does not eliminate film grain when using this feature, but in practice, that's little consolation since the noise reduction itself proves to be practically useless.

C69KS handles upscaling quite well. The tested 576p material looks surprisingly decent – a significant amount of detail is preserved, and the algorithm adds a subtle "rounding" effect to sharp edges, making the image appear more cohesive. However, the smoothing of tonal transitions is lacking. The television practically cannot improve them, leaving the image in a somewhat raw state. With older materials, this can be simply exhausting, as the lack of additional processing highlights all imperfections.

The QN990F can easily be called one of the fastest televisions in the world. In 4K mode, it can display images at a frequency of up to 240 Hz, which until now has been more associated with gaming monitors than with televisions in the living room. However, in everyday viewing, what matters more is how it handles 8K signals at 120 Hz – and it performs very well here too. Motion remains smooth, and the television manages without a hitch even with the most demanding content. Additionally, there is a motion smoother, called "Picture Clarity." With it, you can adjust the image to your own preferences – leave a slight cinematic stutter or switch to maximum smoothness, which works great, for instance, in sports broadcasts.

C69KS offers a simplified motion improvement panel in movies, allowing you to adjust the intensity of the effect using a slider. This makes it easy to match the smoothness to your own preferences. The possibility of using higher refresh rates is also a plus – even though the panel operates natively at 4K at 60 Hz, lowering the resolution to 1440p allows you to enable 120 and 144 Hz modes, both on consoles and PC. This sounds like great news, but in practice, the image at these settings suffers from significant motion blur. The effect is noticeable enough that the overall experience feels simply mediocre and loses its appeal in everyday use.

It must be said directly – the QN990F is one of those TVs that screams it was designed with gamers in mind. Samsung has been developing its gaming solutions for years, but here we have a true package. Sure, the lack of Dolby Vision support in games is a downside that will always come up in discussions. However, apart from that, the list of features is truly impressive. To start, we have Game Bar – a handy menu that allows you to quickly check and change game-related settings. You can see, for example, VRR is turned on, the frame rate, or the aspect ratio settings. It's like a small "dashboard," allowing you not to dig deep into the menu to make adjustments. Speaking of VRR: yes, variable refresh rate is present here and works flawlessly. Additionally, there's ALLM, which automatically switches the TV 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 number of ports makes the biggest impression. Four wireless HDMI 2.1 ports are already great news because you don't have to choose whether to connect the console, the receiver, or maybe even the PC. There's plenty of room here for everything. And if we add an additional micro HDMI (which we recommend connecting directly to consoles), hidden in the housing, we practically have five inputs in full 2.1 standard. Add to that support for high refresh rates – 120 Hz in 8K or even 240 Hz in 4K – and we get a TV that not only keeps up with the new consoles but also feels ready for consoles that are yet to come.

If we overlook the smearing and lack of native 4K at 120 Hz, the C69KS impresses with how well it performs during gaming. We get everything you can expect from a gaming television: variable refresh rate (VRR), automatic switching to game mode (ALLM), Dolby Vision Gaming mode, and a reasonably functioning HGiG. The TV can also operate at 120 and even 144 Hz at lower resolutions, allowing for smoother gameplay on console or PC. Additionally, there is a clear Game Bar that lets you quickly glance at key settings during gaming. As a result — despite a few limitations — the C69KS can be a truly successful screen for gamers.