LG OLED C4 vs Samsung QN90F / QN92F

The results of HDR materials are definitely among the better ones. Practically every film significantly exceeds the 700 nits barrier, allowing for a very realistic image. Of course, none of them surpasses the magical thousand, yet the combination of such results and unlimited contrast and black effectively boosts the outcome optically. The last of the scenes, featuring a full-screen burst of sunlight, is actually less bright than the others, although it still represents a commendable level. It is also worth mentioning the excellent coverage of the DCI-P3 colour palette, which will allow for achieving extremely vivid colours.

The Samsung QN90F can truly shine with brightness. In our measurements, it achieved over 2200 nits, which directly translates to the viewing experience. In practice, this means that when a film features a very bright scene – for example, a sunrise in The Meg – the screen looks as if it is actually lit by natural light. This is not just a number from a chart, but a real sense of image intensity! However, the television may not always deliver this full power. With smaller details like reflections or lamps, brightness drops to 500–700 nits. This is a deliberate decision by the algorithms – it allows for better control of the contrast between large and small elements, preventing the image from losing balance. Importantly, this is still a huge improvement compared to last year's QN90D, where similar details were often almost invisible, shining at just 200 nits. Here, the HDR effect is much more consistent and credible. The only downside is the colours. The DCI-P3 coverage has stalled at 91%, which in this price bracket can be considered a rather average result.

The best factory mode implemented in the tested television was "Filmmaker". It was this mode that we used during all tests. This mode proved to be quite good in terms of colour reproduction; however, other shortcomings effectively detracted from the enjoyment of viewing. Starting with the most basic aspect, the white balance, it was easy to notice that it was marked by a dominance of red, which overall changed the characteristics of the image. We could thus see a strong yellowing of the whites and a shift of all colours towards warmer shades. The gamma, which is a curve just as important, if not more so, was quite significantly lowered, resulting in a considerable drop in contrast, except at the beginning of the graph, where the television insidiously lost details. That’s all regarding SDR materials. Taking a closer look at films with a wide dynamic range, we can observe exactly the same phenomenon of yellowing of the white balance as in films with a standard colour palette. The EOTF curve, which replaces our gamma curve, is practically perfect and cannot be faulted.

The colour reproduction of the QN90F was tested in Filmmaker mode and, as is often the case with Samsung televisions, this mode proves to be the best starting point straight out of the box. However, this does not mean that the image is free from flaws. The white balance in both SDR and HDR content was surprisingly good – the colours did not drift in any direction and even in its factory settings, it looked solid. A problem arose with the gamma curves and EOTF, which dictate how the television manages brightness. Here, the QN90F significantly brightened the entire image, causing blacks and colours to lose their intensity, and the overall effect resembled that of an applied milky filter. Fortunately, Samsung, unlike many competitors in the miniLED world, provides the user with plenty of tools to control the settings that we do not find with other manufacturers, such as Chinese producers. Therefore, we decided to see if we could squeeze the full potential out of the QN90F because we know that such a high-end series is capable of much more.

As we mentioned earlier, LG televisions are equipped with advanced tools for carrying out the calibration process. We therefore used them to model the image in the way that the director intended. And without modesty, we must admit that we achieved this phenomenally. Both SDR and HDR materials present a level that clearly indicates that this is how a film should look. It is worth looking at the colour errors on the "ColorChecker" palette here, where practically none of them exceeds "1", apart from two samples.

After our adjustment of the settings, the QN90F displayed what it is truly capable of – and it must be admitted that this is 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 state, but only after gamma calibration did it manage to get close to reference values. The same is true for HDR content, where the EOTF curve post-adjustment presents mature and cohesive results. Indeed, in some films, it is noticeable that the smallest elements of the image are slightly brightened, and with a limited number of dimming zones, there is still a risk of halo effect. However, it should be remembered that such phenomena are characteristic of all miniLED televisions, and it is difficult to expect miracles even from the QN90F. The most important thing is that after calibration, the television delivers an image that, in terms of representing the director's vision, confidently competes with many OLED screens available on the market.

Once again, we will take a look at the function responsible for smooth gradation, but we will also address the one that aims to improve the quality of lower-quality materials. The default smoothing of tonal transitions, as we have seen, was not the worst, but it can still be improved. The function has a slider, which allows us to adjust its strength. We recommend using the first one, as it yields very good results and does not blur important details.

Image scaling in LG C4 is quite good; however, it cannot be said to be without flaws. The image is slightly sharper by default, although not in a very noticeable way. Admittedly, there are jagged edges on the trees, but this is not a major issue compared to other manufacturers.

QN90F handles upscaling very well. Materials in lower resolutions, even SD, are enhanced to a clear and sharp image, in which a lot of detail in the background can be seen. This is a significant advantage, as the television makes older content or everyday television look considerably better than on most budget screens. However, the issue of overscan remains, which is the trimming of the screen edges, and this cannot be turned off in Samsung TVs. This can cause some subtitles on the screen to disappear or Auntie's face from the wedding on the VHS tape to be slightly cut off. 😉

Digital image processing also works well. In the menu, we find a function called "noise reduction," which can smooth tonal transitions and improve the reception of lower quality materials, e.g. from YouTube. At the medium setting, the effect is most beneficial – it does not heavily interfere with details, while eliminating the problem of "stepping" in colours. However, it is worth remembering that the function can be quite aggressive and removes natural grain from older films, so it is best to use it in moderation.

The maximum refresh rate that we can set on the LG G4 is 144 Hz. Naturally, this is only possible when connecting the television to a very powerful PC. In other cases, we will be operating at a maximum refresh rate of 120 Hz, which is recommended if we primarily want to watch sport or content with a lot of motion dynamics. For those requiring high fluidity of the image, the manufacturer has implemented a multi-step motion smoother called "TrueMotion". It has been divided into two separate sliders that adjust the sharpness of moving images (De-Blur) and judder (De-Judder). Both sliders can be set within a range from 0 to 10, with each degree affecting the degree of smoothing, allowing everyone to find their golden mean.

The LG OLED C4 panel features an average response time of less than 1 ms (which directly results from our measurements), allowing for an incredibly clear image that is unattainable for LCD televisions, whose response times can be as high as several milliseconds. This is clearly visible in the pictures from the "UFO Test," showing no trailing blur behind the object.

The QN90F is equipped with a panel that has a maximum refresh rate of 165 Hz, and although this advantage will primarily be appreciated by PC gamers, it is still worth highlighting. In films 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 is of greater importance here. With the "Motion Clarity" setting, we can adjust the picture to our own preferences. The blur reduction option is responsible for fluidity and ghosting in sports. Meanwhile, the "judder reduction" function improves motion smoothness in productions shot at 24 frames, such as films and series. If we set it high, the film appears smoother and more fluid than it was actually shot. Lower values, on the other hand, preserve its cinematic "rawness" with a visible film frame.

We can already say that LG C4, like practically every OLED television from the manufacturer, is exceptionally good in terms of compatibility with consoles and PCs. Thanks to the implementation of four full bandwidth HDMI 2.1 ports at 48 Gbps, the manufacturer has included all features that enhance the gaming experience, among which we find simultaneous support for FreeSync and G-Sync technology. With such a tandem, gamers with a graphics card from AMD or Nvidia can confidently opt for C4. However, what should delight the players requiring the highest possible quality the most is the simultaneous implementation of HDR Dolby Vision and HGIG mode. The first is particularly important as it works with extremely low input lag in all settings.

A standard in the Korean manufacturer's televisions is also the implementation of GameBar, allowing for quick adjustments of settings "on the fly" without the need to exit the game. It also enables image adjustments for visually impaired individuals, which is a very nice touch. Another important piece of information is that when VRR technology is enabled, we will not experience a drop in contrast. This is, of course, due to the panel's design and the absence of conventional backlighting. However, it is normal for shades of grey to flicker slightly, although this is a characteristic feature of this function regardless of the manufacturer and television.

In summary: LG C4, just like all of the manufacturer's OLEDs equipped with high refresh rate panels and HDMI 2.1 ports, creates a harmonious whole with consoles. In practice, it is a complete television, and if we expect the highest possible performance in gaming, C4 will be an ideal choice.

QN90F has almost everything to be the perfect television for gamers. There’s no need to remind anyone of features like four HDMI ports, VRR, ALLM, or refresh rates reaching even 165 Hz. The Game Motion Plus mode deserves great praise, as it is a unique motion smoother for games. Thanks to this, it adds a few “artificial” frames and makes the image generated from the console look smoother than it should. This is a very unique solution in the world of televisions – rival systems usually do not offer this – and that is why Samsung has had a strong selling point 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 lineup due to the release of software version 1131, which restored the crucial feature for gamers, HGiG.

So why do we say "almost" the perfect screen? Unfortunately, like in recent Samsung models, we noticed an issue with the lack of the HGiG feature. This solution allows the television to leave the control of tone mapping up to the console, so that games look exactly as intended by the creators. What's worse, this feature was previously present and disappeared after software updates. Instead of minor improvements, we got a step back. It’s a shame, because without this absence, the QN90F could truly be the ideal choice for gamers in the miniLED category.