LG OLED C4 vs TCL C6KS / C69KS / Q6CS

The HDR performance of the LG OLED C4 is impressive, firmly placing it in the higher tier. Most films exceed 700 nits, delivering a highly realistic image. While none surpass the 1,000-nit mark, the combination of these results with the TV’s infinite contrast and perfect blacks significantly enhances the visual experience. The final scene, with a full-screen flash of sunlight, is slightly less bright than the others but still maintains a solid level of brightness. Another highlight is the excellent DCI-P3 colour gamut coverage, which ensures incredibly vibrant colours. The HDR technology in the LG OLED C4 delivers exceptional colour and detail reproduction. The dynamic tone mapping feature optimises brightness levels, ensuring ideal light reproduction in every scene, even in the most demanding high-dynamic films.

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.

The best factory mode on the tested television was "Filmmaker," which served as the basis for all evaluations. In terms of colour reproduction, this mode performed reasonably well; however, certain flaws significantly detracted from the overall viewing experience. The most fundamental issue was the white balance, which exhibited a noticeable dominance of red, skewing the image characteristics. This resulted in a pronounced yellow tint to whites and a general shift of all colours towards warmer tones.

The gamma, an equally crucial—if not more important—aspect, was notably lowered, leading to a marked reduction in contrast. Additionally, the television frequently lost detail at the start of the gamma curve. These issues were most apparent in SDR content.

When examining HDR materials, the same yellowing effect in the white balance was observed, as seen with SDR content. However, the EOTF curve, which replaces the gamma curve for HDR, was near perfect and left little room for criticism.

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.

As mentioned, LG televisions come with advanced tools to facilitate an accurate calibration process. By utilising these tools, we meticulously adjusted the image to align with the director’s original vision. Without overstating, the results were outstanding. Both SDR and HDR content now achieve a level of visual fidelity that reflects how films are intended to be seen.

Examining the colour accuracy on the "ColourChecker" palette reveals impressive results, with almost all colour errors falling below a delta of "1," aside from two minor exceptions. Post-calibration, the LG OLED C4 demonstrated a marked improvement in colour reproduction, particularly in SDR and HDR modes. Testing the TV after calibration highlighted its capacity for delivering exceptionally accurate colours, underlining the high calibre of this model. The LG C41LA offers a stunningly precise colour palette, sure to satisfy even the most discerning viewers.

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.

Let us revisit the function responsible for smooth gradation and consider its role in improving lower-quality materials. The default smoothing of tonal transitions, while decent, can be further enhanced. The feature includes a slider for adjusting its strength, and we recommend selecting the first option. This setting strikes a balance, offering excellent results without compromising important details through unnecessary blurring.

The image scaling on the LG C4 is commendable, though not entirely without flaws. By default, the image appears slightly sharper, though not to an intrusive degree. While jagged edges on elements like trees are occasionally visible, this issue is relatively minor compared to similar offerings from other manufacturers.

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 LG G4 supports a maximum refresh rate of 144 Hz, achievable only when connected to a high-performance PC. Otherwise, the television operates at a maximum of 120 Hz, the recommended setting for viewing sports or content with fast-paced motion. For those prioritising smooth image quality, LG has included a versatile motion smoothing feature called "TrueMotion." This function is split into two adjustable sliders: De-Blur, which sharpens moving images, and De-Judder, which reduces jitter. Both sliders offer a range of settings from 0 to 10, enabling users to fine-tune the motion smoothness to their preference.

The LG OLED C4 boasts an impressive average response time of less than 1 millisecond, as confirmed by our measurements. This results in exceptional image clarity, far surpassing LCD televisions, which often have response times of several milliseconds. This clarity is evident in tests like the "UFO Test," where no trailing blur is visible behind moving objects.

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.

The LG C4, like nearly all OLED televisions from the manufacturer, excels in its compatibility with consoles and PCs. With the inclusion of four full-bandwidth HDMI 2.1 ports supporting 48 Gbps, the TV incorporates a range of features to enhance the gaming experience. Notably, it offers simultaneous support for FreeSync and G-Sync, making it an ideal choice for gamers using AMD or Nvidia graphics cards. For those seeking the best possible gaming quality, the integration of HDR Dolby Vision and HGIG mode is particularly impressive. HDR Dolby Vision operates with remarkably low input lag across all settings, ensuring smooth and responsive gameplay.

A standout feature in LG's televisions is the GameBar, which allows users to adjust settings in real-time without leaving the game. This includes options for customising the image for viewers with visual impairments, a thoughtful addition. Additionally, enabling VRR (Variable Refresh Rate) does not result in a loss of contrast—a benefit of the OLED panel's self-emissive technology, eliminating the need for conventional backlighting. While some slight flickering of grey tones may occur, this is a characteristic of VRR technology across all manufacturers.

In summary: The LG C4, like the brand's other OLED models equipped with high-refresh-rate panels and HDMI 2.1, provides a seamless and immersive gaming experience. For gamers demanding top-tier performance, this TV is an outstanding choice.

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.