LG OLED G4 vs Samsung QN990F

LG G4 guarantees an incredibly vivid HDR effect, placing the television among the very best. The equipment of the highest model in the producer's 2024 portfolio with the second generation of micro-lens technology (MLA) has achieved a maximum brightness level of 1474 nits in real scenes. The only area where the product from the Korean manufacturer may lag behind LCD televisions with Mini LED backlighting is during the full-screen scenes featuring a lot of white. If we disregard the latter type of scene, the average result would be even higher. It is also worth mentioning scenes with very fine details, where each one shines at full intensity, which is not as evident in non-OLED televisions. The combination of such brightness and wide coverage of the DCI-P3 palette makes HDR materials more engaging than ever before.

The Samsung QN990F belongs to the bright televisions category, and this is immediately evident in tests. In measurements, it achieved around 1300 nits, which in practice allows for enjoying films as their creators intended. Bright scenes have the right intensity, lights shine, and the experience is truly cinematic. In standard test patterns, sequences number 1, 3, and 5 performed best – there, brightness maintained around 800-1000 nits, and the image looked very natural. In more challenging segments, it could drop to around 600 nits, but even so, the level remained sufficient for details to be clearly visible. However, it should be added that in highly contrasting shots, the halo effect returns – the same one we mentioned regarding black levels. Bright elements can leave a halo on dark backgrounds, and this stands out immediately. Since we are dealing with a QLED, the colour palette is expanded, and the colours appear striking. The problem is that with such a flagship model, we expected better numbers. 91% DCI-P3 coverage and about 67% BT.2020 are results that can be considered solid, but not outstanding. This gives a vibrant and appealing image, yet the competition in this and lower price tiers can showcase even more.

The best factory mode in terms of colour reproduction was "Filmmaker". This was the one we used during our tests. Let's check how its characteristics looked before the calibration process. Looking closely at the white balance first, we can notice a significant dominance of red and green. As a result, the image had a warm yellowish hue. Such characteristics are typically observed in "Cinema", "Filmmaker" or similarly named modes. The effect of this colour balance was clearly visible in both SDR and HDR content, which after switching from "Standard" mode appeared distinctly yellow. Now, let's move on to two graphs that are responsible for the brightness characteristics and consequently the contrast of the image. The first one (Gamma), representing materials with a standard colour palette, performed decently. For most of the time, midtones and bright whites were reproduced very accurately; however, it noticeably lost the darkest details, which merged into a black blob. Conversely, HDR materials, represented by the EOTF curve graph, exhibited a significant drop in contrast due to a strong boost in brightness. The colours themselves also posed a problem, as can be seen on the "ColorChecker" graph, since they were noticeably under-saturated.

We tested the QN990F in Filmmaker mode, which is the best available right out of the box. Right from the start, we noticed several significant errors. The biggest issue concerned white balance. Due to too little blue, and also improper ratios between red and blue, the image – especially in scenes with a lot of white – appeared too yellow, and at times even orange. On the Color Checker palette, these errors didn't look dramatic as they hovered around a value of 4, but in everyday viewing, especially with strong whites, they were most noticeable. We also observed issues with brightness management – the television struggled to maintain detail in the smallest parts of the image, mainly due to the way it controls the backlighting zones. Fortunately, Samsung offers a lot of room for adjustment when it comes to calibration settings. We know that with the right calibration, much more can be extracted from this screen.

The manufacturer has implemented extensive support for the calibration process in its LG televisions for many years. We therefore used 2- and 20-point greyscale adjustments, as well as an advanced CMS (Colour Management System), and got to work. As you can see, thanks to the procedure carried out, each parameter has significantly improved. The use of tools allowed for the achievement of extremely beneficial effects, which include: studio colour reproduction, recovery of details in dark areas of the image, appropriate brightness characteristics, and suitable colour saturation. This brings us as close as possible to the reference image, which is what the film director saw on the preview monitor. It is worth noting that the LG G4 televisions alone allow for even deeper intervention in image quality thanks to the ability to calibrate with 3D LUTs. However, this is a solution recommended only for post-production or graphic studios.

After completing the calibration, we managed to bring the white balance back to order and eliminate the previous shortcomings in the shades of blue. As a result, the image no longer looked as if it had a slightly yellowish filter applied – the whites are purer, and the overall presentation is much more natural. We also managed, to some extent, to tame the brightness characteristics in HDR content. The television now handles detail retention in blacks significantly better and does not lose them to the same degree as before. However, when we look at the EOTF curve and the way the QN990F reproduces brightness in films, it is evident that it still tends to accentuate details in dark areas more strongly. This is a characteristic feature of Mini-LED technology and, more specifically, the way it is managed by the QN990F, which is practically impossible to completely eliminate. Despite this, after calibration, the image appears much more natural, mainly due to the correct exposure of white light. The final effect is definitely more pleasant to perceive and closer to what we expect from a flagship television.

The tested television did not perform particularly well with materials rich in tonal transitions, as a result of which we could observe a strong posterisation effect. However, there is a partial remedy for this issue. The manufacturer has equipped the LG G4 with a smoothing system called "Gentle Gradation," which we can apply at three levels: Low, Medium, and High. Each of these options guarantees quite a high effectiveness of smoothing on light colours, although it is low on darker ones. We recommend primarily using the first one, as the other two interfere with the director's intentions by removing film grain.

When watching lower-quality materials, the efficiency of the television during upscaling is extremely important. The image from the tested television is sharp and clear. However, one should pay attention to the jagged edges of fine details and minor issues around characters, such as the creation of halo effects, which occurs due to the sharpening imposed by LG G4 even when the lowest value on the slider, that is 0, is set. It is worth noting that this represents a certain change compared to the LG G3, which did not impose such strong image sharpening, even when the appropriate slider was set to position 0.

The biggest praise for the QN990F should be given for its upscaling. The processor responsible for "lifting" classic television to 8K resolution does quite well. While watching material in 576p signal, we had no illusions that we would suddenly see a miracle in advertising style, where the image magically transforms into crystal-clear 8K. Nevertheless, the end result was surprisingly good; the image looked clean and sharp. It’s just a shame that the television, like most Samsung models, has an overscan issue, slightly cropping the edges of the screen from the left side.

When it comes to image processing, Samsung offers a feature called "noise reduction," which in theory should improve tonal transitions in older materials, where they are usually more visible. Unfortunately, we felt quite disappointed here. The feature performs poorly – it does not handle unwanted stripes and can introduce its own artifacts. On the plus side, the television does not remove film grain when using this feature, but in practice, that is a poor consolation since the noise reduction itself proves to be virtually useless.

The maximum refresh rate that we can set on the LG G4 is 144 Hz. Naturally, this is only possible when the LG G4 is connected to a very powerful PC. Otherwise, we will operate at a maximum refresh rate of 120 Hz, which is recommended if we primarily want to watch sports or content with high motion dynamics. For those requiring high image fluidity, the manufacturer has implemented a multi-level motion smoother called "TrueMotion". This 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 in the range from 0 to 10, with each level affecting the degree of smoothness, allowing everyone to find their golden mean.

The LG OLED G4 panel features an average response time of 0.78 ms (as directly derived from our measurements), enabling an incredibly clear image, unattainable by LCD televisions, which can have response times of several milliseconds. This is perfectly illustrated by the images from the "UFO Test", which show no trailing blur behind the object. Moreover, the LG OLED G4 test revealed that the television offers the ability to precisely adjust the motion smoothing function, allowing users to select the ideal level of image interpolation. We particularly appreciated this during fast-paced actions in video games, where the LG G4 performed exceptionally well, minimising any blurring. Thanks to OLED technology, this model eliminates so-called ghosting, ensuring that the image remains sharp even in the most dynamic sporting or cinematic scenes.

QN990F can comfortably be called one of the fastest televisions in the world. In 4K mode, it is capable of displaying images at a frequency of up to 240 Hz, which until now has been more associated with gaming monitors than with televisions in the living room. However, in everyday viewing, what matters more is how it handles the 8K signal at 120 Hz – and here it performs very well too. Motion remains smooth, and the television manages without a hitch even with the most demanding content. Additionally, there is the motion smoother, i.e. "Picture Clarity". Thanks to it, one can adjust the image to their own preferences – leaving a slightly cinematic judder or switching to maximum fluidity, which works exceptionally well, for example, in sports broadcasts.

The LG G4 television supports all the features that make up the HDMI 2.1 standard. During testing, each of them activated without the slightest problem, which allows us to consider the television as designed for gaming. Their functionality will surely be appreciated by both console users and those connecting the LG G4 to a computer. It is also worth mentioning the correct implementation of the HGIG (HDR Gaming Interest Group) mode, which ensures that games mastered to brightness levels exceeding the maximum luminance of the LG G4 will correctly map tones, and the game's visuals will remain true to the original.

A nice touch is the existence of a special GameBar, which we can call up at any moment to check game parameters, but most importantly, to change them quickly. More importantly, enabling VRR technology does not degrade contrast, which is very common in televisions that feature local dimming or Mini LED backlighting. Of course, this is thanks to the OLED panel itself, characterised by pixel self-emission. As a matter of editorial obligation, we will only mention a slight grey flicker, which is somewhat normal after enabling VRR.

In summary, the LG G4, like practically all OLED televisions, is an ideal product for all kinds of games and online competitions. With fully-fledged HDMI 2.1 connections with a full bandwidth of 48 Gbit, features such as VRR, ALLM, G-Sync, FreeSync, or gaming in HDR Dolby Vision will bring much joy.

It must be said outright – the QN990F is one of those televisions that practically scream that they were designed with gamers in mind. Samsung has been developing its gaming solutions for years, but here we have a truly comprehensive set. Sure, it lacks Dolby Vision support in games, which is a downside that will always come up in discussions. However, aside from that, the list of features is impressively extensive. To begin with, we have the Game Bar – a handy menu that allows you to quickly check and change gaming-related settings. You can see, for example, the enabled VRR, frame rate, or aspect ratio settings. It’s like a little “dashboard,” making it unnecessary to dig deep into the menu to make adjustments. Speaking of VRR: yes, variable refresh rate is present here and works flawlessly. And there's ALLM, which automatically switches the television to game mode as soon as the console is powered on. These may seem like small details, but together they make using the QN990F simply comfortable and hassle-free.

However, the most impressive aspect is the number of ports. Four wireless HDMI 2.1 ports are already great news, as there is no need to choose whether to connect the console, the amplifier, or perhaps even a PC. There’s ample space for everything here. And if we add another micro HDMI (which we recommend connecting directly to the console), hidden in the casing, we practically have five inputs in full 2.1 standard. Let’s also add support for high refresh rates – 120 Hz at 8K and even 240 Hz at 4K – and we get a television that not only keeps up with the new consoles but also feels ready for consoles that are not yet available.