Samsung OLED S90D / S94D (WRGB OLED) vs TCL C6KS / C69KS / Q6CS

In the tested film scenes, the television Samsung S90D achieves impressive brightness results, exceeding the 1000 nits barrier in the first four shots, which can be considered an outstanding result. In the case of the last shot, where a full-screen flash of sunlight is visible, the brightness drops to around 500 nits, but still remains at a very good level. Additionally, the television impresses with a DCI-P3 colour gamut coverage measurement of 98%, ensuring an extraordinarily rich and realistic colour reproduction, further enhancing the picture quality. This result makes the Samsung S90D an ideal choice for those expecting high-quality images in a variety of lighting conditions.

And what about HDR? Here, the C6KS performs quite well and – as has become a recurring theme of 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 keep in mind 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 blacks. This is quite a reasonable compromise. Most viewers will definitely appreciate deep, "true black" more than additional micro-details, the display of which could cause the screen to appear greyed out. This is the nature of local dimming technology in this price range, and one must be aware of it. It is also worth noting that the TCL C69KS (C6KS) has an additional PFS coating, which is marketed under the slogan of QLED technology. 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% here.

The S90D television has been tested in Filmmaker mode, which offers good colour reproduction, although with some imperfections that may be noticeable to more discerning users. This mode may seem a bit too warm, and users who switched from Standard mode may experience a slight shock. It is worth noting that this situation is caused by poor settings, such as in the white balance, rather than the Filmmaker mode itself. In both SDR and HDR content, the device exhibits drops in blue colour, making colours warmer than they should be. In practice, this means that some shades, such as sky blue or skin tones, may appear less natural and more tinged with pink or yellow. The Colour Checker test confirms these deviations, showing shifts towards warmer tones. In SDR content, the gamma graph indicates slight fluctuations, resulting in a minimally darker image, especially in shadows. This can affect less defined details in darker scenes. Conversely, in 4K HDR materials, the EOTF curve is above the recommended line, leading to overly bright displays in certain parts of the image, which can cause clipping in the brightest areas. Overall, Samsung S90D presents a solid picture right out of the box, but for the best effects, especially with more demanding content, additional calibration is recommended.

Unlike the more expensive C6K model, the tested C6KS does not have an option in the menu labelled as Filmmaker Mode. Is this a reason to cry? Absolutely not. Our tests have shown 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 characteristic 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 gives you better colours – the answer is no, in both cases the base is the same and requires slight adjustments.

After calibration, the Samsung S90D television in movie mode looks even better than one might have expected. The white balance, for both HD and 4K HDR content, has been improved almost to perfection. Although minor flaws can still be noticed, they are minimal enough not to significantly affect the picture quality. The colours are more balanced, which translates to a natural reproduction of details, especially in scenes requiring a precise colour palette. It is worth noting that this model in this size is equipped with a WOLED panel, which has less coverage of the wide colour gamut and does not offer as rich colours as, for example, the 65-inch version, which is equipped with a QD-OLED panel.

Contrast has also seen significant improvement. The gamma graph post-calibration is much closer to the expected line, providing better balance between bright and dark areas of the image. The EOTF curve, which prior to calibration showed issues with overexposed scenes, now presents better results. This effect allows for greater detail retention in bright parts of the image, especially in HDR materials.

Thanks to the white balance adjustment, the C69KS's tendency to distort colours has been effectively limited, resulting in a very good final effect. After calibration, we will no longer see excessive warming of scenes in SDR or overly cool tones in HDR. However, it is worth noting the brightness characteristics. In SDR content, it is hard to have any objections – the image looks very good, especially in older films, television programmes, or materials from YouTube. It is significantly more challenging to evaluate the television's performance in HDR. Analysis of the EOTF curve suggests correct behaviour, but its practical variant reveals certain limitations. The C69KS can overly brighten the smallest elements of the frame, while at other times, it can dim the entire scene. Thus, calibration brought clear benefits in terms of colour quality, but certain limitations resulting from the local dimming operation and the way it is controlled by the C69KS cannot be overlooked, as we also saw in the C6K test.

Television S90D performs very well at smoothing tonal transitions. Thanks to the applied technology, the transitions between colours are more fluid and natural. There is also the option to use noise reduction, which further smooths tonal transitions, which can be useful in certain situations. However, it is worth remembering that enabling noise reduction can also lead to the smoothing of desirable film grain, which in turn could reduce the cinematic atmosphere of the image. For this reason, caution is advised when using this feature, as it is better to leave the natural grain that adds character and authenticity to the viewed content.

Samsung, as always, does not disappoint and excels in the area of scaling images from lower resolutions. The S90D Samsung television effectively processes lower resolutions, as can be seen in the visible image. The outline of the model is clear and accurate and, as a result, looks natural and detailed. Moreover, the branches of the trees are well-rendered, showing no significant jaggedness, which could diminish the image quality. Thanks to effective scaling, even materials in lower resolution present attractively on the screen, pleasing users who prefer various sources of content such as regular antenna/cable television.

The C69KS handles upscaling quite well. The tested 576p material looks surprisingly decent – a considerable amount of detail is retained, and the algorithm adds a slight "rounding" effect to sharp edges, making the image appear more cohesive. The performance in smoothing tonal transitions is less impressive. The television practically cannot improve them, leaving the image in a rather raw state. With older material, this can be quite tiring, as the lack of additional processing highlights any imperfections.

Samsung S90D TV is equipped with a 120 Hz panel, with the possibility of "overclocking" to 144 Hz with the appropriate PC configuration, providing exceptional motion fluidity. Samsung has been offering a variety of sharpness settings on a ten-point scale for years, allowing users to adjust the display to their preferences. In the UFO test, thanks to the use of an OLED panel, there's no sign of any smearing. The pixel response is instantaneous and perfectly captures dynamic movements. In this aspect, OLED technology is considered one of the best on the market. The picture is extremely sharp and detailed, even during fast actions, making the S90D TV an ideal choice for gamers and sports enthusiasts.

C69KS offers a simplified motion enhancement panel in films, allowing the adjustment of effect intensity with a slider. This makes it easy to match fluidity to personal preferences. The ability to use higher refresh rates is also a plus – although the panel operates natively at 4K at 60 Hz, lowering the resolution to 1440p enables 120 and 144 Hz modes, both on consoles and PC. This sounds like great news, however, in practice, the image at these settings exhibits significant motion blur. The effect is so pronounced that the overall presentation appears merely average and loses its appeal for everyday use.

The Samsung S90D TV is perfectly adapted to the needs of gamers, offering four HDMI 2.1 ports that support key features such as Auto Low Latency Mode (ALLM), Variable Refresh Rate (VRR), and HDR Gaming Interest Group (HGIG). With these technologies, gamers can enjoy smoother and more responsive gameplay, significantly affecting comfort and performance during intense gaming sessions. An additional advantage of the television is the special Game Bar, which allows for easy management of game settings. This functionality enables quick adjustments to parameters such as changing the TV's screen aspect ratio, which can be useful in various games and types of gameplay. Users can easily customise their preferences, making the use of the TV during gaming even more convenient and enjoyable. As for PC users, the TV pleasantly surprises. When connected to a computer, the panel is capable of achieving a refresh rate of 144Hz, and users of Nvidia or AMD graphics cards can enjoy features such as G-Sync and FreeSync. It should be noted, however, that the TV does not support Dolby Vision, which may be a drawback - but it's worth bearing in mind that Dolby Vision is not as popular for games as it is for films. Nevertheless, the S90D TV still offers excellent features for gamers, making it a great choice for gaming enthusiasts who seek top-notch picture quality and modern technological solutions.

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