LG UT8100 (IPS) vs TCL P7K / P79K

The LG UT8100 television unfortunately does not meet expectations in the HDR effect category. A peak brightness of only 300 nits on the luminance chart is well below the required value to fully enjoy HDR effects. In practice, the image resembles SDR quality more than true HDR, which is particularly evident in demanding high-contrast scenes. The coverage of the DCI-P3 colour palette is only 82%, which further limits the ability to present vibrant and rich colours. Instead of impressive visual experiences, we receive a muted and washed-out image. For those looking for a television to fully utilise HDR content, the LG UT8100 model turns out to be quite disappointing.

When it comes to assessing HDR performance, we need to be clear and straightforward without any marketing fluff: the P7K/P79K is not and never was meant to be a champion in this area. The maximum peak brightness that this panel can generate hovers around just 300 nits. This represents a threshold, a sort of thin red line between what can be considered barely satisfactory HDR signal and what is, in reality, only slightly better than standard dynamic range (SDR), unfortunately leaning towards the latter. Synthetic tests confirmed this harsh reality – our measurements taken during movie sessions showed that the luminance in key bright scenes rarely exceeded 200-250 nits. Therefore, this is not a TV that would allow content created in a wide tonal range to truly shine, and that must be openly acknowledged.

Unfortunately, the issue of colour reproduction is presented just as conservatively. Although the manufacturer positions this model within the "QLED" family, owing to the use of a PFS LED filter, the results do not match the heightened expectations. The coverage of the wide DCI-P3 colour gamut reaches only 86%. Compared to the market, this is at best an average result, since most devices that utilise additional layers to expand the colour spectrum easily achieve values at a minimum of 90-92%.

The Filmmaker Mode on LG UT8100, while theoretically the best for watching movies, has significant issues. The biggest problem is the white balance – drops in blue cause a noticeable yellowing of the image, visible in both HD and 4K content. These issues are confirmed by measurement results in the Colour Checker test, which indicate significant deviations in colour reproduction.

In terms of brightness characteristics, both HD and 4K content exhibit a large tonal boost. The gamma curve in both cases remains well below the reference value of 2.4, which leads to excessive brightening of darker elements of the image. A similar problem is evident in the EOTF curve – in the case of 4K content, the TV struggles to manage brightness correctly, resulting in issues with screen brightness. This means the factory settings of this model require significant adjustment to achieve better picture quality.

Every reliable assessment of image quality must start with selecting the most optimal, factory preset mode. In the case of the tested P7K/P79K model, the choice was made without hesitation for the "Film" mode. It is the mode that presents an image closest to the intentions of its creators, avoiding both the exaggerated brightness of the dynamic mode and the excessive dimming known from eco settings. And it must be admitted that, for a device in this price range, the factory calibration is surprisingly decent, although it is not without a few stumbles. The most noticeable shortcoming turned out to be the not entirely correctly set white balance. A slight dominance of the blue component gives the image a subtly cool, frosty character, straying from the ideal neutrality that the director intended to show us. The television handles the reproduction of greyscale in the standard dynamic range much better – the gamma curve is almost exemplary. The only slight reservation can be made for the darkest parts of the image, where a delicate deviation from the norm causes a loss of some detail in the shadows. The most significant challenge, however, for the TCL software was interpreting the HDR signal, as illustrated by the EOTF curve. The television follows its own, rather free path here – the darkest details are disproportionately brightened, followed by a noticeable slowdown in brightness increase for mid-tones. Fortunately, most of these imperfections are of a software nature, which can be eliminated. With that thought in mind, we proceeded to the process of professional calibration.

After calibrating the Filmmaker Mode, the gamma has been aligned to practically perfect, reference values, which has significantly improved the overall tonal characteristics in HD content. 4K HDR content also looks better, although some issues are still visible at the extreme ends of the graph, where the curve deviates from the ideal. The EOTF curve performs worse since the TV struggles to maintain the correct brightness values. As a result, the image in some scenes may be too bright or slightly dim, which stems from the device’s design. Nevertheless, the calibration brought significant improvement, particularly for HD content, where the tonal balance and colour reproduction are now at a much higher level.

The calibration process turned out to be spot on, especially in the context of standard dynamic range (SDR) content. We successfully managed to eliminate the tendency of the television to showcase cool tones, restoring white to its natural neutrality. Moreover, the precise adjustment allowed us to correct a slight error in the gamma curve, enabling the darkest parts of the image to regain proper depth, without any signs of unnatural brightness. The results are measurable and impressive – in the ColorChecker test, the vast majority of colour reproduction errors fell below the perceptual threshold, achieving a deltaE value of below 2. This is a result that more expensive models would not be ashamed of. Unfortunately, in the case of HDR content, we encounter a wall in the form of the panel's structural limitations. And although we managed to bring the colours into line, the software's specifics mean that the television still adapts brightness in its own way, as evidenced by the persistent, non-standard EOTF curve. To summarise, calibration adds tremendous value, but it is important to be aware that it won't overcome certain physical barriers. The slightly elevated blacks, resulting from the lack of local dimming, and limited peak brightness mean that HDR content won't always be able to showcase its full potential. This is simply not the main task of this display; its true strength, especially after professional tuning, lies in viewing SDR material.

The fluidity of tonal transitions is also correct, although the effect depends on the settings. The update improved the operation of the smooth gradation function, smoothing transitions better than before, but introduced minor issues with detail loss, e.g. on textures.

Image scaling on LG UT8100 performs very well. The image presents itself decently, with no major issues regarding edge aliasing. Details are preserved at a satisfactory level, making materials of lower resolution look really solid on this television. As a result, users can enjoy watching older content without any noticeable defects in quality.

After a series of harsh evaluations, thankfully, it’s time for some praise, and this is deserved by the TCL AiPQ image processor for its work in the field of digital processing and content scaling. It should be noted right away that we are not talking about the level known from flagship models; nonetheless, in the price segment represented by the P7K/P79K, the results achieved are more than solid. The function that smooths tonal transitions performs particularly well, effectively eliminating posterization, which are the characteristic bands often visible in materials with higher compression, for instance, from choose.tv. The algorithm can elegantly remove unwanted gradients, which ultimately looks really good. The television also handles upscaling competently, which means the task of raising low-resolution materials to 4K standard. The resulting image, although it may seem a bit too sharp out of the box, is fortunately not a problem. The software allows for free adjustment of this parameter using a sharpness slider, allowing the final appearance to be easily tailored to personal preferences.

LG UT8100, equipped with a 60 Hz panel, is particularly suited for those watching movies. The television offers the TruMotion system with a de-judder effect adjustment, which allows users to tailor the smoothness of the picture – from more choppy to exceptionally smooth, resembling a soap opera effect, depending on user preferences.

The issue of fluidity and sharpness of motion image is inextricably linked to the fundamental parameter of the panel, and in the case of the TCL P7K/P79K, we are dealing with a panel that has a native refresh rate of 60 Hz. This specification at the outset defines its capabilities and makes it hard to unequivocally recommend it to enthusiasts of dynamic sports broadcasts. During quick camera movements, the image loses sharpness, and the panel also shows a slight tendency to smudge, which may be noticeable to more sensitive viewers. Fortunately, not everything in this aspect has been left to chance. The manufacturer has implemented a simple motion smoothing system, which is primarily used in film materials recorded at 24 or 30 frames per second. Thanks to a dedicated slider, the user can decide on the final nature of the motion – from maintaining a fully cinematic, slightly jerky image, to achieving a very smooth, almost theatrical effect. It is a simple yet effective tool that allows one to adjust the viewing experience to their own preferences.

LG UT8100 offers basic features for gamers, such as ALLM and Game Bar, which makes it easier to access settings. The TV also supports HGiG, improving picture quality in HDR games. Unfortunately, the lack of support for Dolby Vision and VRR limits the device's capabilities, as does the 60 Hz panel, which excludes support for 120 Hz resolution. This model is more suited for less demanding gaming applications.

Although on paper the native 4K@60Hz matrix might suggest that the TCL P7K/P79K is not a TV tailored for gamers, the reality turns out to be surprisingly different. On the contrary, the manufacturer has ensured a rich set of features that make it a very friendly companion for next-generation consoles. Onboard, we find key technologies such as ALLM, which provides automatic switching to low-latency mode, and VRR, or variable refresh rate, which eliminates screen tearing. The list is rounded off with support for Dolby Vision Gaming and a simple yet functional Game Bar. However, the real and extremely pleasant surprise is something else. It turns out that the TV effortlessly supports a high refresh rate signal of 120Hz, but at lower resolutions – 1080p and 1440p. This is fantastic news for console owners, who know how rarely games run in native 4K at a full 120 frames per second. The option to choose between higher resolution and doubled smoothness is therefore an incredibly sensible compromise.

In summary, while the P7K/P79K may not be the target screen for the most passionate, tournament gamers, it offers a package of options for casual or occasional console users that is hard to find among many competitors at this price point.