LG 55 B4 vs Sony X90L

The brightness results in HDR materials LG B4 are very good. It is true that none of them exceed 1000 nits, although the luminance stability is excellent and looks practically the same in every scenario. The only moment where the tested television performs worse is the last scene, although this should not come as a surprise. Large frames filled with a lot of white have always been, and will likely continue to be, somewhat of a weakness for OLED televisions. However, the combination of perfect contrast, black levels, and brightness in the LG B4 allows for a full spectrum of the HDR effect. Additionally, the incredibly high coverage of the DCI-P3 colour gamut, which reached 99%, deserves recognition. As a result, colours look incredibly vibrant and stunning.

HDR on the Sony X90L television looks promising. The luminance chart indicated that the TV has a solid power reserve, achieving a maximum of 1000 nits in synthetic tests. But how does this perform in real-world scenarios? In scenes such as the opening of Life of Pi or the final sequence from The Meg, the TV is capable of delivering that power on HDR content, reaching around 800 nits. Unfortunately, displaying small light elements on a black background, like in the scene from Sicario 2, presents greater challenges for the X90L – here the results reach around 600 nits. Nevertheless, when looking at competitive models with mini-LED technology, the effect looks very good and can shine enough to impress us. The colour gamut coverage is also noteworthy, with a result of 96% for DCI-P3 and 76% for BT.2020, which indicates good colour reproduction in HDR content.

The best factory mode prepared by the manufacturer is "Filmmaker," and we used it throughout the entire testing procedure. We must admit that the unit we received straight out of the box had quite decent colour reproduction. The biggest issue in both SDR and HDR content turned out to be white balance. In the former, there was a strong dominance of red, resulting in a noticeable yellow tint in the displayed image, particularly evident on skin tones and whites. In high-quality materials, this colour was also pronounced, but due to a lack of blue, there were also signs of green visible. Besides these shortcomings, we also encountered issues with greyscale and the colours themselves.

The best mode on Sony televisions is the IMAX Enhanced mode. Although IMAX is mainly associated with the cinema experience, the colour reproduction out of the box is average here. In the case of lower quality materials, such as HD – regular television or YouTube – it's worth paying attention to the white balance. It suffers from a shortfall in red and excessive dominance of blue, which gives the image a pinkish hue. The brightness characteristic, or gamma, for HD content is quite acceptable, but a slight boost can cause the image to appear washed out and look as if it’s behind a light fog.

For 4K HDR content, the situation is somewhat different. The white balance shows a significant boost in blue, which makes the image unnaturally sharp and gives it an artificial feel. Such an exaggeration in colour reproduction may not appeal to everyone, especially if one prefers more realistic tones. Additionally, the EOTF curve in Sony X90L looks quite acceptable at first glance. However, at the end of the graph, there are certain fluctuations that suggest the television is trying to maintain the correct brightness to avoid overexposing larger elements.

LG B4 has been providing very advanced calibration tools in its TVs for years. We can even say that as the only manufacturer on the market, it allows for such deep intervention in image adjustment. Thanks to these, we were able to calibrate the device so well. The evidence of this is the extremely low deltaE errors, which can be said to stand at a reference level. Both SDR and HDR materials now look exactly as the film director intended. It is no coincidence that TVs of this brand are most often used as preview screens for various graphic or post-production studios.

Sony offers many tools for improving picture quality, including two extra picture modes that we decided to use during testing and apply calibration to. This solution greatly simplifies the calibration process and is very effective, provided you have the right tools. In the case of HD content, white balance was almost perfectly aligned – only one shade of grey exceeds an error value of "1", which is a great result. The same can be said for the brightness characteristic (gamma), which presents almost perfectly, with microscopic deviations of around 0.01.

For 4K HDR content, the situation is not as ideal. Although white balance has been significantly improved, it was not possible to completely eliminate the dominance of blue. Nevertheless, errors in the Colour Checker test only occasionally exceed the value of "2", which means that picture distortions are practically unnoticeable. When it comes to the EOTF curve, it's worth activating the filter in the top right corner "EOTF in Films" – the graph looks correct, but the TV struggles with illuminating very small elements, which is due to the limited number of backlight zones. Despite these minor errors, it's thanks to the calibration that the IMAX Enhanced mode in the Sony X90L makes watching movies feel like a true cinema experience.

In this paragraph, we will take another look at the tonal transition smoothing feature, but we will also check how the TV handles lower quality material. As we have managed to check, the setting responsible for smooth gradation works quite effectively, although it has its weaker moments. While the feature works well with SDR content, it becomes less useful with HDR content. Even at the lowest of options, it blurs essential details, so we advise against using it.

The image scaling on LG B4 is rated fairly moderately positively. Although there is no edge splitting, the image itself is naturally "soft". We can change this by adjusting the sharpness slider.

The Sony X90L television features a smooth tonal transition function known as Gentle Gradation, which is incredibly effective. Even at the "low" setting, the effects are satisfactory, but at the "medium" setting, it works like a dream – we recommend using this option for the best results. The image scaling on the Sony X90L is simply excellent. The image is not overly sharpened, which gives a natural effect and makes everything look cohesive. It's clear that the engineers have really put effort into this aspect, creating a solution that impresses and performs well in everyday use. This means that even when watching content like regular television or YouTube, where the image is by nature not stunning, you can enjoy a smooth, coherent, and visually pleasing experience.

The maximum refresh rate we can set on the LG B4 is 120 Hz. This is the absolute minimum for those who require high image smoothness. The manufacturer has implemented a multi-level motion smoother called "TruMotion". It has been divided into two separate sliders that adjust the sharpness of moving images (De-Blur) and stuttering (De-Judder). Both sliders can be set in the range from 0 to 10, with each level affecting the degree of smoothness, so everyone can find their sweet spot.

The LG OLED B4 panel features an average response time of 0.1 ms (which directly results from our measurements), allowing for an incredibly clear image, unattainable for LCD TVs, which have response times of even several milliseconds. This can be clearly seen in images from the "UFO Test", showing no trace of blur trailing behind the object.

Sony X90L with a 120 Hz display is an excellent choice for both gamers and film enthusiasts. The television is equipped with the Motion Flow smoothing feature, which allows for adjusting motion smoothness using two sliders: "smoothness" and "clarity". The "smoothness" slider controls the level of motion fluidity, which affects the reduction of image stuttering, while "clarity" is used to reduce blurriness and enhance motion sharpness, which is especially useful in dynamic scenes.

The LG B4 television is equipped with four full-fledged HDMI 2.1 ports with a full bandwidth of 48Gbps. All functions corresponding to this standard activated without any issues, and throughout the entire testing procedure, they caused no problems. The combination of such extensive functionality and low input lags leads us to say that the tested television is truly designed for gaming. This is not surprising, considering that the manufacturer has always placed great emphasis on this. Therefore, we can enjoy both a properly implemented HGIG mode and gameplay in Dolby Vision with low latency. Such a tandem will surely attract the attention of all passionate gamers for whom quality is the most important.

A standard feature in televisions from the Korean manufacturer 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 individuals with visual impairments, which is an extremely nice touch. Another important piece of information is that when the VRR technology is turned on, we will not experience a drop in contrast. This is, of course, due to the construction of the panel and the lack 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 the television.

In summary: The LG B4, like all OLEDs from the manufacturer equipped with 120Hz panels and HDMI 2.1 ports, creates a harmonious whole with the console. In practice, it is a complete television, and if we expect the highest possible efficiency in gaming, the B4 will be the ideal choice.

Sony X90L is a TV that performs well in terms of compatibility with consoles and features for gamers. Its 120 Hz panel and two HDMI 2.1 ports with a bandwidth of 48 Gb/s allow for smooth playback of high-resolution games at high frame rates. Gamers can also take advantage of the ALLM feature, which automatically switches the TV to low latency mode, and VRR, which ensures smooth gameplay without frame tearing. The Game Bar is an added bonus – an intuitive tool that provides quick access to essential settings and gaming features, making it easier to control the gameplay.

Unfortunately, when it comes to HDR in games, the Sony X90L has its limitations. It lacks support for HGiG, a standard that many gamers consider crucial for accurate HDR representation in games. While the TV supports Dolby Vision, which theoretically could enhance image quality in games, the practical implementation of this feature is problematic. Dolby Vision in game mode comes with very high input lag, making gameplay less comfortable and precise movements more difficult. Additionally, Dolby Vision cannot be enabled alongside VRR. This means that despite numerous advantages, gamers seeking the perfect HDR in games may feel unsatisfied.