LG UR781 vs SAMSUNG S90F (WOLED)

In HDR mode, LG UR781 unfortunately does not impress with its brightness. In tests on five screens, the television achieved only around 200 nits, which is quite a low value for HDR standards. This brightness is similar to levels typical for SDR, causing HDR effects to be insufficiently pronounced, and the image may appear less impressive, especially in dynamic, bright scenes. In HDR mode, it has certain limitations in colour reproduction. This means that colours may not be as intense and rich as in televisions that manage better with a wide colour gamut. In practice, this can make the image less vibrant and dynamic, and HDR effects will not be as spectacular as one might expect. Additionally, UR781 LG has some issues with accurately reproducing colours in HDR mode, resulting in content that may look less vivid.

Does the S90F handle not only black, but also bright parts of the image? Definitely yes. Tales of OLEDs as “dark screens” can slowly be regarded as a myth. The Samsung S90F, like the LG C5 based on a very similar panel, achieves brightness exceeding 1000 nits. This is a value entirely sufficient to enjoy impressive and dynamic HDR imagery – both in films and series. Most of the scenes we tested look superb, with well-defined highlights and high contrast. Of course, OLED technology still has its limitations – in very bright, full-screen sequences, such as the test pattern from the film The Meg (picture 5), the television may noticeably dim the image. However, it should be emphasized that such scenes are rare. It can be considered that the HDR effect is good enough that even mid-range OLED models like the S90F can provide a cinematic experience in the home living room.

The colour reproduction in LG UR781 in Filmmaker Mode, which although is the best mode available from the factory settings, is not without its flaws. Firstly, the issue is white balance, where the graph shows dips in blue colour levels. This phenomenon results in a shift of hues towards yellow tones, causing the image to appear warmer than it should. Such deviation means that the colours on the screen are not naturally reproduced, which can be particularly noticeable in scenes with a white or neutral background. This can be confirmed by the Test Color Checker, which showed that some colours "shift" into other shades, meaning that the LG UR781 television does not display colours in accordance with reality. This distortion can affect the visual experience, making movie scenes seem less realistic, and details might be displayed in inappropriate colours, negatively impacting the overall image quality.

In terms of contrast, the analysis of the gamma graph revealed drops to a level of 2.0, whereas the optimal value should be 2.4. This means that the television may display darker parts of the image brighter in certain scenes, which reduces their depth and dynamics. Additionally, on the EOTF curve, which is responsible for brightness reproduction, an unnatural spike was observed at the beginning. This phenomenon can result in excessive brightness boost in the brightest parts of the image, leading to loss of detail in very bright scenes.

The Samsung S90F, like most modern televisions, offers many picture modes, but – in line with our testing tradition – we assessed it in the best one, which is the Filmmaker mode. This way, the image looks significantly more natural than in the default, often oversaturated settings. It was neither overly saturated nor artificially muted – just closer to what should be seen. Of course, "more correct" does not mean "ideal". Unfortunately, our S90F unit had considerable issues with white balance, especially in the blue range, resulting in a slightly yellowish filter being applied to most scenes. Someone might say it looks more "cinematic" – because it is warmer – but let's not kid ourselves, George Lucas did not film Star Wars in sepia 😉 (you will find the comparison with the scene as always below).

Additionally, in HDR materials, there was a noticeable issue with brightness management. The EOTF curve showed a clear "spike" in brightness – the television brightened the image more than it should have, which made some effects look overly intense and diverged from the reference. Fortunately, some of these problems can be eliminated through professional calibration – you will read about its effects later in the review.

After calibration, the colour representation in SDR content is quite good. The white balance has been effectively improved, resulting in natural, balanced hues across various scenes. The gamma has also been adjusted, providing more precise detail in the shadows and highlights of the image. As a result, the LG UR781 television performs well in everyday use, offering solid colour quality and clear, well-balanced images in SDR mode.

However, the situation is worse for HDR content. The LG UR781 television does not support a wide colour gamut, which limits the depth and richness of colours that HDR can offer. The EOTF curve deviates from the ideal, resulting in excessive highlighting of details in the bright parts of the image. Unfortunately, this results in significant colour reproduction errors, as confirmed by tests on the Colour Checker. Additionally, the low brightness level of the panel further negatively impacts the quality of HDR images, causing dynamic range effects to be not fully realised, and colours to appear washed out.

Despite some shortcomings in HDR mode, the television has improved significantly after calibration, especially in SDR content. The improvement in white balance and gamma has greatly enhanced image quality, providing a more natural and cohesive colour representation. Compared to its state before calibration, the difference is clear, and the LG UR781 television now offers better performance in everyday use, particularly in the standard dynamic range.

After calibration, we managed to eliminate practically all the previously mentioned errors. Older films in SDR quality finally look as they should – without the sepia effect or artificial aging of the image. The atmosphere of the classics returns to its rightful place (you’re welcome, Star Wars fans), and the colours no longer resemble an Instagram filter.

One of the key changes was also the improvement of brightness characteristics in HDR content. We managed to control the EOTF curve in almost a reference manner. Yes, the most demanding users may spot minimal deviations in brightness, but honestly – most viewers won’t even notice that. And it's no wonder, because the vast majority of errors are below a ΔE value of 3, which is below the threshold of visibility. After calibration, the S90F (WOLED) truly becomes an excellent display – one that provides nearly perfect picture quality.

Now let’s address the function of smoothing tonal transitions and its impact on overall image quality. As illustrated in the photo on the left, this function performs exceptionally mediocrely; we selected the "low" level, which does not improve quality but also does not blur the film grain. There is the option to increase the power of this function, which would soften the gradation; however, one must reckon with the fact that the image will be too softened in some scenes.

On the other hand, regarding image scaling, the television does not perform exceptionally, which can be particularly noticeable with lower resolution content. The LG UR781 television applies a slight, artificial sharpness boost, which makes the image appear sharper, but this primarily results from the overlay of artificial contours. For some users, this can be an advantage, as they prefer more vivid, accentuated details. However, this is a subjective matter—such an effect may not appeal to everyone, especially if they desire a more natural look to the image.

Digital Image Processing in the S90F:

Fortunately, Samsung, as in most of its models, effectively manages the unwanted posterisation effect in the S90F. The feature responsible for this aspect is noise reduction, which does a decent job of smoothing tonal transitions and eliminating unnatural colour connections – of course, within its limitations. Unfortunately, it operates rather aggressively, so using it comes with compromises. In addition to improving gradation, it can also remove film grain or gently soften facial features. In this case, the choice is yours – do you prefer a more "clean" image, or do you want to preserve the original texture of the material?

Image Scaling in the S90F:

In this year's model, Samsung implemented its own AI processor – NQ4 Gen3, which does quite well with upscaling. In our test scenes, the television effectively "pulled up" lower quality towards artificial 4K – the image was more pleasant to view, and the differences in sharpness between native and scaled content were minimal. Unfortunately, behind all this AI marketing facade lies a certain shortcoming. The S90F struggles with overscan. If you reach for truly archival materials – e.g. a VHS tape of your parents' wedding – you must expect that the lower part of the image may be cut off. The image adaptation function to resolution simply does not work here as it should.

The LG UR781 television offers quite decent smoothness for films, thanks to the "True Motion" option, which allows users to adjust the level of motion smoothing on a scale from 0 to 10. The user can choose whether they want to preserve a more traditional, cinematic effect with subtle judder (lower settings) or prefer a smoother, theatrical image that, although slightly deviating from the cinematic standard, may appeal to many.

In dynamic sports content and games, the LG UR781 television performs worse. The television has a 60Hz panel, which limits its interpolation capabilities to these values; therefore, it can improve fluidity in films but cannot reduce motion blur. Additionally, the lack of support for 120 Hz and BFI (Black Frame Insertion) technology means that quick movements of objects become blurred, and the response time of the panel is too long, negatively affecting clarity in fast scenes. As a result, the television may not meet the expectations of gamers and sports fans who are looking for a smooth, clear image without motion blur.

The S90F really handles motion excellently – after all, it’s an OLED with a 144 Hz panel, so sports and games look absolutely stunning on it. The image is fluid, clear, and there’s no room for any ghosting or blurring that sometimes plagues cheaper LCDs.

The television is also equipped with motion smoothness settings, allowing you to customise everything to your preference. We have motion blur reduction and judder reduction – you can set it so that the image is super smooth (even to that soap opera effect), or more cinematic, with the classic 24-frame 'choppiness'. The choice is yours; Samsung doesn’t impose anything.

While gaming on the console, the television LG UR781 offers several important features that can affect the gaming experience, but it also has some limitations. A positive aspect is the presence of ALLM (Auto Low Latency Mode), which automatically optimises picture settings by switching the television LG UR781 into low latency mode, which is beneficial for gamers. The television also supports proper implementation of HGiG, meaning HDR games look as intended by the developers.

Unfortunately, it lacks support for Variable Refresh Rate (VRR), which may result in poorer fluidity of gameplay, particularly in more dynamic games. It also does not support Dolby Vision mode for games, which limits the HDR picture quality in games using this format. The television has a panel with a frequency of 60hz, which means it does not support higher frequencies at other resolutions, such as 1080p@120Hz, 1440p@120Hz, or 4K@120Hz, which is a significant drawback for gamers expecting smoother gameplay at higher resolutions. It also lacks support for G-Sync technology, which limits image synchronisation in games.

However, a positive aspect is the presence of the Game Bar feature, which allows quick access to settings for gamers and makes it easier to adjust picture parameters during gameplay.

When it comes to gaming features – the S90F has absolutely nothing to fault. Aside from the lack of Dolby Vision, which is already the norm for Samsung. The television operates at 144 Hz, has four HDMI 2.1 ports, so you can easily connect more than one console or PC. Onboard, we also find the Game Bar – a practical tool that allows you to quickly glance at picture settings, VRR status, ALLM mode, and other useful options. Game Motion Plus also deserves a mention – Samsung's proprietary motion enhancer that is the only one truly functioning sensibly in games. The image appears smoother, but without any artificial effects or slowdowns.

It is also worth mentioning the HGiG feature, which – much to our slight surprise – works correctly. We're mentioning this because Samsung clearly broke something in one of the last updates, and in some models, the option responsible for HGiG simply... disappears from the menu. Setting it up becomes practically impossible. Fortunately, our S90F unit did not have this issue, but the situation is dynamic, so it's worth keeping this in mind and regularly checking for updates and information from the manufacturer.