LG OLED C4 vs Samsung QN90F / QN92F

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.

The Samsung QN90F can truly shine in brightness. In our measurements, it achieved over 2200 nits, which directly translates to the viewing experience. Practically, this means that when a very bright scene appears in a movie – for example, the sunrise in The Meg – the screen looks as if natural light is actually shining on us. This isn’t just a number from a chart, but a real sense of image intensity! However, the TV cannot always deliver that full power. With smaller details, such as headlights or lamps, the brightness drops to 500–700 nits. This is a conscious decision by the algorithms – this way, the contrast between large and small elements is better controlled, and the image does not lose balance. Importantly, this is still a huge improvement compared to last year's QN90D, where similar details were almost invisible, shining at just 200 nits. Here, the HDR effect is much more consistent and credible. The only downside is the colors. The coverage of the DCI-P3 palette stopped at 91%, which can be considered a rather average result in this price range.

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 color reproduction in the QN90F in Filmmaker mode, and as usual with Samsung TVs, this mode proves to be the best starting point right out of the box. However, this does not mean that the image is free from flaws. The white balance in SDR and HDR content was surprisingly good – the colors didn’t shift in any direction, and even in the factory setting, it looked solid. However, a problem arose with the gamma and EOTF curves, which are responsible for how the TV manages brightness. Here, the QN90F significantly brightened the entire image, causing black levels and colors to lose their intensity, and the overall effect resembled a milky filter being applied. Fortunately, Samsung, unlike many competitors in the miniLED world, provides users with a lot of tools to control the settings that we don’t find with other manufacturers, such as Chinese brands. Therefore, we decided to check if it was possible to extract the full potential of the QN90F because we know that such a high series can deliver much more.

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 adjustment of the settings, the QN90F showed what it is really capable of – and it must be admitted that it has one of the best images we have seen on a miniLED screen this year. As we mentioned earlier, the white balance was not a major issue even in its factory version, but only after the gamma calibration were we able to get close to nearly reference values. The same is true for HDR content, where the EOTF curve after correction presents mature and consistent results. Indeed, in some films, it can be noticed that the smallest elements of the image are slightly brightened, and with a limited number of dimming zones, there is still a risk of the halo effect. It should be remembered, however, that such phenomena are characteristic of all miniLED televisions, and it's hard to expect miracles even from the QN90F. The most important thing is that after calibration, the television shows an image that, in terms of conveying the director's vision, confidently competes even with many OLED screens available on the market.

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.

QN90F handles upscaling very well. Materials in lower resolution, even SD, are boosted to a clear and sharp image, showcasing plenty of details in the background. This is a significant advantage because the television makes older content or everyday TV look much better than on most budget screens. However, the issue of overscan remains, which is the trimming of the edges of the screen that cannot be turned off in Samsungs. This can cause some subtitles on the screen to disappear or a relative's face from a wedding on a VHS tape to be slightly cropped. 😉

The digital image processing also works well. In the menu, we find a feature called "noise reduction," which can smooth out tonal transitions and improve the reception of lower-quality materials, such as from YouTube. In medium setting, the effect is the most beneficial – it does not heavily interfere with details while eliminating the "stair-stepping" problem in colors. However, it is important to remember that the feature can be quite aggressive and can also remove natural grain in older films, so it's best to use it in moderation.

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 QN90F is equipped with a panel that has a maximum refresh rate of 165 Hz, and while primarily PC gamers will appreciate this advantage, it is still worth highlighting. In movies or sports broadcasts, we are limited to the classic 120 Hz, but this is not a cause for concern. In practice, the additional motion smoother plays a more significant role here. With the "Motion Clarity" setting, we can adjust the image to our own preferences. The blur reduction option is responsible for smoothness and trailing in sports. Meanwhile, the "judder reduction" function improves motion smoothness in productions recorded at 24 frames, such as movies and series. If we set it high, the film looks smoother and more fluid than it was actually filmed. Lower values, on the other hand, maintain its cinematic "rawness" with the visible film frame.

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.

QN90F has nearly everything to become the perfect television for gamers. Things like four HDMI ports, VRR, ALLM, and refresh rates reaching up to 165 Hz are probably well-known. It deserves high praise for the Game Motion Plus mode, which is a proprietary motion smoothing technology for games. Thanks to this, it can add a few “artificial” frames and make the image generated from the console look smoother than it should. This is a very unique solution in the world of televisions – competitive systems usually do not offer this – which is why Samsung has had a strong bargaining chip among gamers for years, even despite the lack of support for the still niche Dolby Vision in games.

[UPDATE] We have updated our tests of Samsung televisions from the 2025 model year due to the release of software version 1131, which restored the crucial gaming feature HGiG.

So why are we writing about a “nearly” perfect screen? Unfortunately, similar to recent Samsung models, we noticed an issue with the lack of the HGiG feature. This solution allows the television to leave control over tone mapping to the console, so that games look exactly as the creators intended. Worse still, this feature was previously present, and it disappeared after software updates. Instead of minor tweaks, we received a step back. It’s a shame because if it weren't for this absence, the QN90F could truly be the perfect choice for gamers in the miniLED category.