Samsung QD-OLED S90D / S94D vs LG OLED C4

In the HDR effect category, the Samsung S90D delivers remarkable performance. On the luminance graph for up to 10% of the window, the television surpasses the 1000 nits mark, which is a notable achievement. However, in the film scenes we tested, these values were slightly lower. In scenes with fullscreen sun glare the brightness drops to about 500 nits, but this is still considered a very good result. It is also worth noting that this model stands out due to its very high colour gamut coverage, thanks to the QD-OLED panel, giving it an edge over televisions with WOLED panels, which cannot achieve such a wide spectrum of colours.

The results of HDR materials are definitely among the better ones. Practically every film significantly exceeds the 700 nits barrier, allowing for a very realistic image. Of course, none of them surpasses the magical thousand, yet the combination of such results and unlimited contrast and black effectively boosts the outcome optically. The last of the scenes, featuring a full-screen burst of sunlight, is actually less bright than the others, although it still represents a commendable level. It is also worth mentioning the excellent coverage of the DCI-P3 colour palette, which will allow for achieving extremely vivid colours.

The Samsung 65" S90D with a QD-OLED panel has been tested in Filmmaker Mode, which the manufacturer has used for years to deliver optimal picture settings. In this mode, the TV offers a very good image, but there are some shortcomings worth noting.

In terms of white balance, viewers may notice a red dominance in HD content, which can make skin tones appear unnatural and create a warm overall scene, potentially affecting immersion. This issue becomes more apparent in scenes where subtle colour differences are important. The same effect can be observed in 4K HDR content, though the red shift is less pronounced. This shift can prevent certain details and colours from being fully realised, diminishing the naturalness of the image.

As for contrast, the gamma performance is decent but still has some issues. The gamma values fall short of the reference level of 2.4, resulting in bright areas of the image appearing washed out and dark areas lacking detail. This limitation can make certain scenes feel less dynamic and impact the depth and richness of the picture. However, the EOTF curve for contrast in 4K HDR content performs well, showing the TV's ability to handle differences in brightness. That said, these values still fall slightly below the ideal range, indicating room for further optimisation.

Overall, the Samsung S90D in Filmmaker Mode offers solid colour reproduction, but some adjustments are needed to fully unlock its potential, particularly with different types of content.

The best factory mode implemented in the tested television was "Filmmaker". It was this mode that we used during all tests. This mode proved to be quite good in terms of colour reproduction; however, other shortcomings effectively detracted from the enjoyment of viewing. Starting with the most basic aspect, the white balance, it was easy to notice that it was marked by a dominance of red, which overall changed the characteristics of the image. We could thus see a strong yellowing of the whites and a shift of all colours towards warmer shades. The gamma, which is a curve just as important, if not more so, was quite significantly lowered, resulting in a considerable drop in contrast, except at the beginning of the graph, where the television insidiously lost details. That’s all regarding SDR materials. Taking a closer look at films with a wide dynamic range, we can observe exactly the same phenomenon of yellowing of the white balance as in films with a standard colour palette. The EOTF curve, which replaces our gamma curve, is practically perfect and cannot be faulted.

The quality improves more than anticipated after calibrating the S90D television in movie mode. The white balance for HD and 4K HDR content has been fine-tuned to near perfection. While minor imperfections are still noticeable, they are subtle enough not to significantly impact the overall picture quality. Colours have become more cohesive, promoting a natural reproduction of details, particularly in scenes where precise colour representation is essential. It’s important to note that this particular model, in this size, uses a QD-OLED panel, which offers a broader colour gamut compared to other versions of this model equipped with a WOLED panel.

The contrast has also seen a marked improvement. After calibration, the gamma chart is much closer to the expected curve, resulting in a better balance between the bright and dark areas of the image. The EOTF curve, which previously indicated issues with overexposed scenes, now shows significantly better results. This improvement allows for greater preservation of details in the brighter parts of the image, particularly in HDR content.

As we mentioned earlier, LG televisions are equipped with advanced tools for carrying out the calibration process. We therefore used them to model the image in the way that the director intended. And without modesty, we must admit that we achieved this phenomenally. Both SDR and HDR materials present a level that clearly indicates that this is how a film should look. It is worth looking at the colour errors on the "ColorChecker" palette here, where practically none of them exceeds "1", apart from two samples.

The television excels at smoothing tonal transitions, allowing colours to blend seamlessly, resulting in a natural and fluid image. The built-in noise reduction feature can further enhance these transitions, useful in certain situations. However, it is important to note that activating this option may overly smooth out the desired film grain structure, potentially compromising the authenticity and atmosphere of the image. Therefore, caution is advised when using this feature, to maintain the character and depth of the content.

The S90D model handles lower-resolution materials effectively, as demonstrated in the displayed image. The model's silhouette remains sharp and naturally reproduced, with fine details preserved. Additionally, the branches of the trees are well-defined, free from any visible jagged edges that might otherwise degrade the image quality. Thanks to efficient scaling, even lower-resolution content appears attractive on the screen, which is sure to please users who rely on a variety of content sources, such as standard cable or antenna television.

Once again, we will take a look at the function responsible for smooth gradation, but we will also address the one that aims to improve the quality of lower-quality materials. The default smoothing of tonal transitions, as we have seen, was not the worst, but it can still be improved. The function has a slider, which allows us to adjust its strength. We recommend using the first one, as it yields very good results and does not blur important details.

Image scaling in 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. Admittedly, there are jagged edges on the trees, but this is not a major issue compared to other manufacturers.

The S90D TV, featuring a 120 Hz refresh rate matrix and up to 144 Hz in the appropriate PC configuration, delivers excellent motion fluidity. Samsung highlights a range of sharpness settings on a ten-point scale, allowing users to fine-tune the display to their preferences. In UFO tests, the OLED matrix showcases its strengths by eliminating any blurring. The ultra-fast pixel response ensures dynamic movements are faithfully reproduced.

Similar results can be seen in other sizes of this model with a WOLED matrix, which also offer outstanding image fluidity. Organic technology, in this case, is considered among the best on the market. The S90D image, regardless of the matrix type, is exceptionally sharp and detailed, making this television perfect for dynamic scenes, whether for gaming or sports broadcasts. Additionally, its refresh rate and sharpness capabilities guarantee that every movement is smooth and natural, satisfying even the most discerning users.

The maximum refresh rate that we can set on the LG G4 is 144 Hz. Naturally, this is only possible when connecting the television to a very powerful PC. In other cases, we will be operating at a maximum refresh rate of 120 Hz, which is recommended if we primarily want to watch sport or content with a lot of motion dynamics. For those requiring high fluidity of the image, the manufacturer has implemented a multi-step 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 within a range from 0 to 10, with each degree affecting the degree of smoothing, allowing everyone to find their golden mean.

The LG OLED C4 panel features an average response time of less than 1 ms (which directly results from our measurements), allowing for an incredibly clear image that is unattainable for LCD televisions, whose response times can be as high as several milliseconds. This is clearly visible in the pictures from the "UFO Test," showing no trailing blur behind the object.

The S90D television is an excellent solution for gamers, offering a range of advanced features that elevate gaming quality to a new level. Equipped with HDMI 2.1 standard, the model supports modern technologies such as VRR (Variable Refresh Rate) and ALLM (Auto Low Latency Mode). Thanks to these solutions, the image is incredibly smooth, and the response to commands is instantaneous, which is crucial in dynamic titles. Additionally, the S90D supports HLG (Hybrid Log-Gamma) as well as G-Sync and FreeSync image synchronisation. This enables a perfect connection with Xbox, PlayStation, or PC, eliminating issues with tearing and stuttering. The built-in operating system offers the Xbox Game Pass app, providing access to a vast library of games directly from the television. This solution makes gaming even more convenient and accessible. The Game Bar feature provides quick access to essential information, such as current settings, performance statistics, and the ability to adjust image options. This allows for on-the-fly display parameter modification, which is extremely useful during intense gameplay. Despite lacking support for Dolby Vision, the S90D still offers excellent HDR image quality, allowing for full utilization of the potential of games and movies. As a result, the S90D represents a unique combination of modern technologies, outstanding image quality, and intuitive features, perfect for any gaming enthusiast.

We can already say that LG C4, like practically every OLED television from the manufacturer, is exceptionally good in terms of compatibility with consoles and PCs. Thanks to the implementation of four full bandwidth HDMI 2.1 ports at 48 Gbps, the manufacturer has included all features that enhance the gaming experience, among which we find simultaneous support for FreeSync and G-Sync technology. With such a tandem, gamers with a graphics card from AMD or Nvidia can confidently opt for C4. However, what should delight the players requiring the highest possible quality the most is the simultaneous implementation of HDR Dolby Vision and HGIG mode. The first is particularly important as it works with extremely low input lag in all settings.

A standard in the Korean manufacturer's televisions 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 visually impaired individuals, which is a very nice touch. Another important piece of information is that when VRR technology is enabled, we will not experience a drop in contrast. This is, of course, due to the panel's design and the absence 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 television.

In summary: LG C4, just like all of the manufacturer's OLEDs equipped with high refresh rate panels and HDMI 2.1 ports, creates a harmonious whole with consoles. In practice, it is a complete television, and if we expect the highest possible performance in gaming, C4 will be an ideal choice.