LG OLED G4 vs Samsung QN990F

LG G4 guarantees an incredibly vibrant HDR effect, placing the television firmly at the top of the rankings. The highest model in the manufacturer's 2024 portfolio, equipped with the second generation of microlens technology (MLA), has achieved a maximum brightness level of 1474 nits in real scenes. The only area where the product of the Korean manufacturer may fall short compared to LCD televisions with Mini LED backlighting is during a full-screen scene featuring a lot of white. If we were to disregard the latter scene, the average result would be even higher. It's also worth mentioning scenes with very fine details, where each one shone at full intensity, which is not as evident in non-OLED televisions. The combination of such brightness and wide coverage of the DCI-P3 color space ensures that HDR materials are more engaging than ever before.

Samsung QN990F is one of the bright televisions, and this is immediately apparent in tests. In measurements, it achieved around 1300 nits, which in practice allows you to enjoy films as their creators intended. Bright scenes have the right strength, lights shine, and the impression is truly cinematic. In standard test patterns, sequences number 1, 3, and 5 performed the best – there, brightness remained around 800-1000 nits, and the image looked very natural. In more difficult segments, it could dip to around 600 nits, but the level was still sufficient for details to be clearly visible. However, it should be added that with such highly contrasted shots, the halo effect returns – the same one we mentioned regarding blacks. Bright elements can leave a glow on dark backgrounds, and this is immediately noticeable. As we are dealing with a QLED, the colour palette is expanded, and the colours present themselves impressively. The problem is that with such a flagship model, we expected better numbers. 91% coverage of DCI-P3 and about 67% BT.2020 are results that can be considered solid but not outstanding. This gives an image that is vibrant and appealing; however, the competition in this and lower price ranges can show even more.

The best factory mode in terms of colour reproduction was "Filmmaker". This is the one we used during our tests. Let's check how its characteristics looked before the calibration process. Taking a closer look at the white balance first, we can notice a significant dominance of red and green colour. As a result, the image had a warm yellow tint. This is the kind of characteristic we usually observe in "Cinema", "Filmmaker", or similarly named modes. The effect of such a colour balance was clearly visible in both SDR and HDR content, which, after switching from "Standard" mode, was distinctly yellowed. Now let's move on to two graphs that are responsible for brightness characteristics, and consequently, image contrast. The first one (Gamma), representing materials with a standard colour palette, performed decently. For most of the time, the midtones and bright whites were represented very accurately, however, it noticeably lost the darkest details which blended into a black patch. On the other hand, HDR materials, represented by the EOTF curve graph, exhibited a significant drop in contrast due to a strong boost in brightness. There was also an issue with the colours themselves as seen on the "ColorChecker" graph since they were noticeably undersaturated.

We tested the QN990F in Filmmaker mode, which is the best out-of-the-box setting available. Right from the start, we noticed a few significant issues. The biggest problem was with white balance. Due to too little blue, as well as incorrect 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 noticed problems with brightness management—the TV struggled to maintain details in the smallest parts of the image, mainly due to how it manages backlight zones. Fortunately, Samsung provides plenty of room for adjustment when it comes to setting corrections. We know that with proper calibration, much more can be extracted from this screen.

The manufacturer has been implementing extensive support for the calibration process in their LG televisions for many years. Therefore, we used 2- and 20-point grey scale adjustments along with an advanced CMS (Color Management System) and got to work. As you can see, thanks to the procedure carried out, each of the parameters has significantly improved. The use of tools has resulted in extremely beneficial effects, which include: studio colour reproduction, recovery of details in dark areas of the image, appropriate brightness characteristics, and proper colour saturation. Thus, we have maximised our approach to the reference image, or the one that the film director saw on the preview monitor. It is worth noting that the LG G4 televisions are the only ones that allow for even deeper intervention in image quality due to the capability to calibrate with 3D LUT matrices. However, this solution is recommended only for post-production or graphic studios.

After carrying out the calibration, we managed to bring the white balance into order and eliminate the earlier shortcomings in shades of blue. As a result, the picture no longer looked like it had a slight yellowish filter – the whites are cleaner, and the whole thing presents itself much more naturally. We also managed to tame the brightness characteristic in HDR content to some extent. The television now handles maintaining detail in blacks much better and does not lose them as much as before. However, when we look at the EOTF curve and how 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, how it is managed by the QN990F, which is practically impossible to eliminate completely. Despite this, after calibration, the picture looks significantly more natural, mainly due to the correct exposure of white light. The final effect is definitely more pleasant to the eye and closer to what we expect from a flagship television.

The tested television did not perform well with content rich in tonal transitions, resulting in a strong posterisation effect. However, there is a partial remedy for this ailment. 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 high smoothing effectiveness on bright colours, though low on darker ones. We recommend primarily using the first one due to the fact that the other two interfere with directorial intentions, removing film grain.

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

The QN990F deserves the highest praise for its upscaling capabilities. The processor responsible for 'lifting' classic TV to 8K resolution does a really decent job. Watching footage in 576p, we had no illusions that we would suddenly see a miraculous transformation like in an advertisement, where the image magically turns into crystal-clear 8K. Nevertheless, the final effect was surprisingly good; the picture looked clean and sharp. It's just a shame that the TV, like most Samsung models, has an overscan issue, which slightly cuts off 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 noticeable. Unfortunately, here we felt quite disappointed. The feature performs poorly – it struggles with unwanted banding and can even introduce its own artifacts. On the plus side, it’s worth noting that the TV doesn’t remove film grain when using this feature, but in practice, that’s a poor consolation when the noise reduction itself turns out to be practically useless.

The maximum refresh rate that we can set on the LG G4 is 144 Hz. Naturally, this is only possible by connecting the LG G4 to a very powerful PC. Otherwise, we will be operating 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 who require high fluidity of image, the manufacturer has implemented a multi-level 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 in the range from 0 to 10, with each increment affecting the degree of smoothing, so everyone can find their sweet spot.

The LG OLED G4 panel features an average response time of 0.78 ms (which directly results from our measurements), allowing for an incredibly clear image, unattainable by LCD televisions, which have response times of even several milliseconds. This is clearly visible in the "UFO Test" images, showing the absence of any trailing blur behind the object. Furthermore, the LG OLED G4 test showed that the television offers the ability to precisely adjust motion smoothing functionality, allowing users to choose the ideal level of image interpolation. We particularly appreciated this during fast-paced action in video games, where the LG G4 performed exceptionally well, minimising any blurriness. Thanks to OLED technology, this model eliminates so-called ghosting, ensuring that the image remains sharp even in the most dynamic sports or movie scenes.

QN990F can easily be called one of the fastest TVs in the world. In 4K mode, it can display images at a frequency of up to 240 Hz, which until now was more associated with gaming monitors than with living room TVs. However, in everyday viewing, what's more important is how it handles an 8K signal at 120 Hz – and it performs very well here too. Motion remains smooth, and the TV handles even the most demanding content without breaking a sweat. Additionally, there's the motion smoother, or "Image Clarity." Thanks to this, you can adjust the picture to your preferences – leave it slightly cinematic with a bit of judder or switch to maximum smoothness, which works brilliantly for things like sports broadcasts.

The LG G4 television supports all features that make up the HDMI 2.1 standard. During testing, each feature activated without any issues, which allows us to consider the television as designed for gaming. Its performance will certainly be appreciated by both console users and those connecting the LG G4 to a computer. It’s also worth mentioning the proper implementation of the HGIG (HDR Gaming Interest Group) mode, which ensures that games mastered to brightness levels beyond the maximum luminance of the LG G4 will correctly map tones, keeping the game image true to the original.

A nice touch is the presence of a special GameBar that we can bring up at any moment to check game parameters, but most importantly, to change them quickly. More importantly, turning on VRR technology does not degrade contrast, which is often a problem in televisions with local dimming or Mini LED backlighting. Of course, this is thanks to the OLED panel itself, characterised by pixel self-emissiveness. As a journalistic note, we will only mention a slight grey flicker, which, however, is somewhat normal when VRR is enabled.

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

It has to be said straightforwardly – the QN990F is one of those televisions that scream they were designed with gamers in mind. Samsung has been developing its gaming solutions for years, but here we have a true package. 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 truly impressive. To start, we have the Game Bar – a handy menu that allows you to quickly check and change game-related settings. You can see things like VRR enabled, frame rate, or aspect ratio settings there. It's like a little “dashboard” so you don’t have to dig deep into the menu to fix something. Since the word VRR was mentioned: yes, variable refresh rate is present here and works flawlessly. Plus, there's ALLM, which automatically switches the television to game mode as soon as the console is turned on. These may seem like small details, but together they make using the QN990F simply convenient and hassle-free.

However, the greatest impression comes from the number of ports. Four wireless HDMI 2.1 ports as standard is already great news, as there's no need to choose whether to connect the console, the receiver, or maybe even the PC. There's comfortably enough room for everything here. And if we add another micro HDMI (which we recommend connecting directly to the console), hidden within the casing, then in practice we have five inputs in full 2.1 standard. Let’s also add support for high refresh rates – 120 Hz in 8K or even 240 Hz in 4K – and we get a television that not only keeps up with the new consoles but also feels ready for consoles that aren’t even out yet.