LG OLED C4 vs Samsung Q6F (IPS)

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.

Unfortunately, the Samsung Q6F is a very dark model. Its peak brightness in HDR does not exceed 250 nits, which is definitely too low to even speak of any "high dynamic range" effect, or HDR. In practice, it's better to stick to content in SDR format, which simply looks more predictable on this TV. Another problem is the global dimming technique – in scenes with a lot of black, the TV drastically dims the entire panel to artificially improve the black levels. This causes the image to become even darker, and brightness can drop below 100 nits. The only consolation is the QLED technology, but even here it's average. The applied quantum dot layer is not top-notch, as the coverage of the DCI-P3 color gamut does not exceed 90%. As a result, colors in HDR content may just seem under-saturated.

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.

We tested the television in Filmmaker mode, which showed us two completely different faces of this model. Looking at SDR content, we were honestly shocked at how good this TV looks straight out of the box. It was really hard to nitpick anything here. Despite a slight “haze” in the white balance or somewhat brightened details in the blacks (which directly results from the IPS panel's design), color errors hovered around the “2” level. This is surprisingly good, even outstanding, considering the price of this device.

On the other hand, what the Q6F displayed in terms of colors after switching to HDR mode was a very unpleasant surprise. The errors in color reproduction and palette were so huge that our charts literally ran out of scale. Of course, since Samsung even in such an inexpensive model offers very advanced calibration possibilities, we decided to approach the subject professionally and check what could be done about it during calibration.

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.

After our calibration, the colors in SDR mode looked even better – the result is quite surprising, as color errors at level "1" are something usually seen in devices costing several thousand dollars. In this regard, the Q6F is really a great screen for everyday television, less demanding series, or movies. Unfortunately, our interference in HDR mode did not bring about a noticeable improvement. The television, due to its poor black levels and low coverage of a wide color gamut, still has significant problems with proper color saturation, especially red. This is an example of a device where HDR mainly exists as a label on the box – for everyday use, we definitely recommend watching content in SDR format.

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.

The Q6F handles upscaling lower resolution content to native 4K very well. The scaling is surprisingly good here, even for such a budget TV from the QLED series. The only downside is when we watch very low-resolution material, like 576p (typical for old DVD players) – then the image may be slightly cropped. This is because the TV does not allow for the Overscan feature to be turned off, which is a common issue with Samsung devices.

The situation is completely different when it comes to digital processing, which is the attempt to smooth the image from unwanted artifacts. Here, the TV completely fails. Although we find a function in the menu called "Noise Reduction", it yields no visible results regardless of the slider setting. The only thing it seems to do is introduce unwanted errors into the image. Despite its presence in the system, we definitely do not recommend using it.

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.

The 60 Hz panel in the Samsung Q6F is the standard in this price range, which makes it a rather average model for dynamic sports or gaming. However, in the case of movies, the TV performs quite well thanks to the smoothing feature. The "Motion Smoothing" option allows you to adjust the fluidity of motion to your own preferences – from maintaining a cinematic feel to full fluidity.

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.

We won’t beat around the bush – the Q6F is not a television designed with gamers in mind. While it does have features like ALLM (Auto Low Latency Mode) and VRR frame synchronization for consoles, the list of benefits pretty much ends there. Besides these basics, the TV offers nothing more that might satisfy those who spend a lot of time in front of a console. It’s a real shame that such a useful tool as Game Bar is missing here, which in Samsung’s higher models allows for quick control of game parameters. In terms of gaming, this is an absolutely basic model and is only suitable for "casual" gamers.