LG UR781 vs TCL C6KS / C69KS / Q6CS

In HDR mode, LG UR781 unfortunately does not impress with its brightness. In tests on five screens, the television achieved only around 200 nits, which is quite a low value for HDR standards. This brightness is comparable to levels typical for SDR, which means that HDR effects are not sufficiently vivid, and the picture may look less impressive, especially in dynamic, bright scenes. In HDR mode, it has certain limitations in colour reproduction. This means that colours may not be as intense and rich as in televisions that handle a wider colour gamut better. In practice, this can make the image less vibrant and dynamic, and HDR effects may not be as spectacular as one might expect. Additionally, UR781 LG has some issues with accurate colour representation in HDR mode, which makes content look less lively.

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%.

Colour reproduction in LG UR781 in Filmmaker Mode, which although it is the best mode available from factory settings, is not without its flaws. First and foremost, the issue is with white balance, where the graph shows dips in the blue colour level. This phenomenon results in a shift towards yellow hues, making the image warmer than it should be. Such deviation means that the colours on the screen are not reproduced naturally, which may be particularly noticeable in scenes with white or neutral backgrounds. This can be confirmed by the Color Checker Test, which showed that some colours "escape" into other shades, indicating that the LG UR781 TV does not display colours accurately. This distortion can affect visual experiences, making film scenes seem less realistic and details may be displayed in incorrect colours, negatively impacting overall picture quality.

In terms of contrast, analysis of the gamma graph revealed drops to a level of 2.0, while the optimal value should be 2.4. This means that the TV may display darker parts of the image brighter in some scenes, reducing their depth and dynamism. Additionally, on the EOTF curve, which is responsible for brightness reproduction, an unnatural spike was noticed at the beginning. This phenomenon may result in excessive brightness boosting in the brightest parts of the image, leading to a loss of details in very bright scenes.

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 calibration, colour reproduction in SDR content is quite good. The white balance has been effectively improved, resulting in natural, balanced hues across different scenes. The gamma has also been adjusted, providing a more precise representation of details in the shadows and bright areas of the image. As a result, the LG UR781 TV performs well in everyday use, offering solid colour quality and clear, well-balanced images in SDR mode.

However, the situation is less favourable for HDR content. The LG UR781 TV does not support a wide colour gamut, which limits the depth and richness of colours that HDR can provide. The EOTF curve deviates from the ideal, leading to excessive highlighting of details in the bright areas of the image. Unfortunately, this approach results in significant colour reproduction errors, as confirmed by tests on the Colour Checker. Additionally, the low brightness level of the panel further negatively impacts HDR image quality, causing the effects of dynamic range to not be fully realised and colours to appear washed out.

Despite some shortcomings in HDR mode, the TV has significantly improved after calibration, especially in SDR content. The enhancement of white balance and gamma has notably increased image quality, providing a more natural and cohesive colour reproduction. Compared to its pre-calibration state, the difference is clear, and the LG UR781 TV now offers better performance in everyday use, particularly in standard dynamic range.

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.

Let's now address the function of smoothing tonal transitions and its impact on overall picture quality. As illustrated by the photo on the left, this function performs exceptionally mediocre; we chose the "low" level, which does not enhance quality but also does not blur the film grain. There is a possibility to increase the strength of this function, which could soften this gradation, but one must consider that the image will be too softened in certain scenes.

On the other hand, regarding image scaling, the television does not perform outstandingly, which may be particularly noticeable with lower resolution content. The LG UR781 television applies a slight, artificial sharpening boost, making the image appear sharper; however, this mainly results from the application of artificial contours. For some users, this may be an advantage, as they prefer more vivid, pronounced details. However, this is a subjective matter—such an effect may not appeal to everyone, especially if they desire a more natural appearance of the image.

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.

The LG UR781 TV offers quite decent smoothness for movies, thanks to the "True Motion" option, which allows users to adjust the motion smoothing level on a scale from 0 to 10. Users can choose whether they want to maintain a more traditional, cinematic effect with a slight stutter (lower settings) or prefer a smoother image with a theatrical quality, which, although slightly deviating from the cinematic standard, may appeal to many.

In dynamic sports content and gaming, the LG UR781 TV performs worse. The TV has a 60Hz panel, which limits its interpolation capabilities to these values; therefore, smoothness can be improved in films, but motion blur cannot be reduced. Additionally, the lack of support for 120 Hz and BFI (Black Frame Insertion) technology means that fast-moving objects become blurred, and the panel's response time is too slow, negatively affecting clarity in fast scenes. As a result, the TV may not meet the expectations of gamers and sports fans who are counting on a smooth, clear image without motion blur.

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.

When playing on a console, the LG UR781 TV offers several significant features that can affect the gaming experience, but it also has some limitations. On the plus side, it includes ALLM (Auto Low Latency Mode), which automatically optimises the picture settings by switching the LG UR781 TV to low latency mode, which is beneficial for gamers. The TV also supports correct implementation of HGiG, meaning HDR games look as intended by the creators.

Unfortunately, it lacks support for Variable Refresh Rate (VRR), which can result in worse gameplay smoothness, especially in more dynamic games. It also does not support Dolby Vision mode for gaming, which limits HDR picture quality in games using this format. The TV has a 60Hz panel, so it does not support higher frequencies at other resolutions, such as 1080p@120Hz, 1440p@120Hz, or 4K@120Hz, which is a significant downside for gamers expecting smoother gameplay at higher resolutions. There is also no support for G-Sync technology, which limits image synchronisation in games.

On the positive side, the presence of a Game Bar feature allows for quick access to settings for gamers and makes it easier to adjust picture parameters during gameplay.

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.