LG OLED C4 vs SAMSUNG S90F (WOLED)

The results of HDR materials are definitely among the better ones. Practically every film significantly exceeds the 700 nits barrier, which allows for a very realistic image. Of course, none of them surpasses the magical thousand, however, the combination of such results along with unlimited contrast and black effectively boosts the visual outcome. The last of the scenes, featuring a fullscreen sun burst, is indeed less bright than the others, although it still represents a respectable level. It's also worth mentioning the excellent coverage of the DCI-P3 colour palette, which will enable the achievement of exceptionally vivid colours.

Does the S90F handle not only blacks but also bright parts of the image? Definitely. The stories about OLEDs as "dark screens" can slowly be regarded as myth. The Samsung S90F, like the LG C5 based on a very similar panel, achieves brightness exceeding 1000 nits. This is a value more than enough to enjoy impressive and dynamic HDR images – both in movies and series. Most of the scenes we tested look stunning, 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 card from the movie The Meg (photo 5), the television may noticeably dim the image. However, it should be emphasized that such scenes are rare. It can be said 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 best factory mode implemented in the tested television was "Filmmaker". That was the one we used during all tests. This mode, in terms of colour reproduction, turned out to be quite decent, although other flaws effectively detracted from the enjoyment of the viewing experience. Starting with the most basic one, which is white balance, it was easy to notice that this was marked by a dominance of red, which completely altered the characteristics of the picture. We could see a strong yellowing of the whites and a shift of all colours to warmer tones. The gamma, which is a graph as equally important, if not more so, was quite severely reduced, resulting in a significant drop in contrast, except for the start of the graph, where the television insidiously lost details. That’s all regarding SDR materials. Looking closely at films with a wide dynamic range, we can observe exactly the same phenomenon of white balance yellowing as in films with a standard colour palette. The EOTF curve, which replaces the gamma chart for us, is practically perfect and cannot be faulted.

Samsung S90F, like most modern televisions, offers many picture modes, but – following our testing tradition – we checked it out in the best one, which is the Filmmaker mode. Thanks to this, the image looks much more natural than in the default, often oversaturated settings. It was neither overly saturated nor artificially dimmed – simply closer to what one should see. Of course, “more accurate” doesn’t mean “perfect”. Unfortunately, our S90F had significant issues with white balance, particularly in the blue color range, resulting in a slightly yellowish filter being applied to most scenes. Someone might say it looks more “filmic” – because it’s warmer – but let’s not kid ourselves, George Lucas didn’t film Star Wars in sepia 😉 (you’ll find a comparison with the scene below as always).

Additionally, in HDR materials, there was an issue with brightness management. The EOTF curve showed a clear “spike” in brightness – the television brightened the image more than it should have, causing some effects to look too intense and deviating from the reference. Fortunately, some of these problems can be eliminated through professional calibration – you’ll read about its effects later in the review.

As we mentioned earlier, LG televisions are equipped with advanced tools for carrying out the calibration process. We used them to model the picture in line with what the director envisioned. And without modesty, we must admit that we achieved this phenomenally. Both SDR and HDR materials present a level that clearly indicates this is how a film should look. It's worth taking a look at the colour errors on the "ColorChecker" palette, where practically none of them exceed "1", except for two samples.

After calibration, we managed to eliminate practically all the previously mentioned errors. Older movies in SDR quality finally look like they should – without the sepia effect or artificial aging of the image. The atmosphere of the classics is back in place (no thanks needed, 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. Admittedly, the most demanding users may detect minimal deviations in brightness, but honestly – most viewers won't even notice that. And it's no surprise because the vast majority of errors fall below the ΔE 3 value, which is below the threshold of visibility. After calibration, the S90F (WOLED) becomes a truly excellent display – one on which you can enjoy nearly perfect image quality.

Once again, we will take a look at the feature responsible for gentle gradation, but we will also address the one that aims to enhance the quality of lower-quality materials. The default smoothing of tonal transitions, as we could see, was not the worst, but it can be improved further. The function has a slider that allows us to adjust its intensity. We recommend using the former, as it produces very good results and does not blur important details.

Image scaling on 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. While jagged edges of trees can be seen, it is not a major issue when compared to other manufacturers.

Digital Image Processing in S90F:

Fortunately, Samsung, like in most of its models, manages to effectively tackle the unwanted posterisation effect in the S90F. The function responsible for this element is noise reduction, which does a pretty good job of smoothing tonal transitions and eliminating unnatural colour blending – of course, within its capabilities. Unfortunately, it works quite aggressively, so using it comes with trade-offs. In addition to improving gradation, it can also remove film grain or slightly soften facial features. In this case, the choice is yours – do you prefer a more "clean" image, or do you care about preserving the original texture of the material.

Image Scaling in S90F:

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

The maximum refresh rate we can set on the LG G4 is 144 Hz. Naturally, this is only possible when connecting the TV 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 a lot of motion dynamics. For those who require high fluidity of the 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 of 0 to 10, with each degree affecting the level of smoothing, allowing everyone to find their sweet spot.

The panel of the LG OLED C4 features an average response time of less than 1 ms (which directly results from our measurements), enabling the achievement of an extremely clear image, unattainable for LCD TVs, which can have response times of up to several milliseconds. This is clearly evident in the images from the "UFO Test," which show no trailing blur behind the object.

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 smooth, clear, and there’s no room for ghosting or blurring, which can sometimes plague cheaper LCDs.

The TV also comes equipped with motion smoothness settings that allow you to customise everything to your liking. We have motion blur reduction and judder reduction – you can set it so that the image is super smooth (even to the point of looking a bit soap opera-like), or more cinematic, with the classic “jumpiness” of 24 frames. The choice is yours, Samsung imposes nothing.

We can now say that LG C4, like practically every OLED television from the manufacturer, is exceptionally good in terms of cooperation with consoles and PCs. Thanks to the implementation of four full-bandwidth HDMI 2.1 ports at 48 Gbps, the manufacturer has embedded all the features that enhance gaming comfort, including simultaneous support for FreeSync and G-Sync technologies. With such a tandem, players with graphics cards from AMD or nVidia can safely choose C4. However, what should please gamers demanding the highest possible quality the most is the simultaneous implementation of HDR Dolby Vision and HGIG mode. The former is particularly important as it operates with extremely low input lag in all settings.

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 allows for image adjustments for people with visual impairments, which is an incredibly nice touch. Another important piece of information is that when VRR technology is enabled, we won’t experience a drop in contrast. This is, of course, due to the design of the panel and the absence of conventional backlighting. It is, however, 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 the manufacturer's OLEDs equipped with high-refresh-rate panels and HDMI 2.1 connections, creates a harmonious whole with consoles. In practice, it is a complete television, and if we expect the highest possible efficiency in gaming, C4 will be an ideal choice.

When it comes to gaming features – the S90F has absolutely nothing to complain about. 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 Game Bar – a practical tool that allows you to quickly preview picture settings, VRR status, ALLM mode, and other useful options. Game Motion Plus deserves special mention – Samsung's proprietary motion smoother that actually works sensibly in games. The image appears smoother, but without any artificial effects or slowdowns.

It's also worth mentioning the HGiG feature, which – and this may be a slight surprise – works correctly. We bring this up because Samsung clearly messed something up in one of the recent updates, and in some models, the option responsible for HGiG simply... disappears from the menu. Setting it up becomes almost 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 new software versions and information from the manufacturer.