LG UT8100 (IPS) vs TCL P7K / P79K

The LG UT8100 television unfortunately does not meet expectations in the HDR effect category. The peak brightness of only 300 nits on the luminance graph is significantly 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 color palette is only 82%, which further limits the ability to present vibrant and rich colors. Instead of impressive visual experiences, we get a muted and washed-out image. For those looking for a television to fully utilize HDR content, the LG UT8100 model proves to be highly disappointing.

When evaluating the HDR effect, we must make it clear and without marketing embellishment: the P7K/P79K is not and was never meant to be a master in this field. The maximum peak brightness that this panel can generate is only around 300 nits. This is a borderline value, a sort of thin red line between what can be considered a barely satisfactory HDR signal and what is really not much different from standard dynamic range (SDR), unfortunately leaning towards the latter. Synthetic tests found brutal confirmation in reality – our measurements taken during movie screenings showed that luminance in key bright parts of the content rarely exceeded the threshold of 200-250 nits. Therefore, this is not a television that would allow content produced in a wide tonal range to truly shine, and we must openly acknowledge that.

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

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

As for brightness characteristics, both HD and 4K content feature a high tonal boost. The gamma curve in both cases remains well below the reference value of 2.4, leading to excessive brightening of darker elements in the image. A similar problem is evident in the EOTF curve – in the case of 4K content, the TV struggles with proper brightness management, resulting in issues with screen brightness. This means that the factory settings of this model require significant adjustment to achieve better image quality.

Every reliable image quality assessment must begin by selecting the most optimal factory mode. In the case of the tested model P7K/P79K, the choice was confidently made for the "Film" mode. It is this mode that presents an image closest to the creators' intentions, avoiding both the exaggerated brightness of 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 free from a few stumbles. The most noticeable flaw turned out to be an imperfectly adjusted white balance. A slight dominance of the blue component gives the image a subtly cool, chilly character, thus deviating from the exemplary neutrality that the director wanted to show us. The television performs much better in reproducing the grayscale in a standard dynamic range – the gamma curve is executed almost perfectly. A minor reservation can only be made for the darkest parts of the image, where a slight deviation from the norm causes a loss of some detail in the shadows. The most serious challenge for TCL's software, however, was the interpretation of the HDR signal, which is 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 midtones. Fortunately, most of these imperfections are software-related issues that can be eliminated. With this thought in mind, we proceeded to the professional calibration process.

After calibrating the Filmmaker Mode, the gamma has been aligned to practically ideal, reference values, which significantly improved the overall tonal characteristics in HD content. 4K HDR content also looks better, although some issues are still visible at the end of the graph, where the curve deviates from the ideal. The EOTF curve performs worse, as the television struggles to maintain appropriate brightness values. As a result, the image in some scenes may be overly bright or slightly dimmed, which stems from the device's design. Nevertheless, the calibration has brought significant improvements, especially in the case of HD content, where tonal balance and color reproduction are now at a much higher level.

The calibration process turned out to be a home run, especially in the context of standard dynamic range (SDR) content. We successfully managed to eliminate the TV's tendency to emphasize cool tones, restoring the whites to their natural neutrality. Furthermore, precise adjustments allowed us to correct a slight error in the gamma curve, so the darkest areas of the image regained their proper depth, without a trace of unnatural brightening. The effects are measurable and impressive – in the ColorChecker test, the vast majority of color reproduction errors fell below the perceptual threshold, achieving a deltaE value below 2. This is a result that would not shame much more expensive constructions. Unfortunately, in the case of HDR content, we hit a wall in the form of the inherent limitations of the panel itself. And although we managed to bring the colors in line, the software's specifics mean that the TV still adapts brightness in its own way, as evidenced by the persistent, non-standard EOTF curve. In summary, calibration brings tremendous added value, but one must be aware that it cannot overcome certain physical barriers. A slight boost in black levels, resulting from the lack of local dimming, and limited peak brightness mean that HDR content will not 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 the viewing of SDR materials.

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

Image scaling on LG UT8100 performs very well. The image presents itself decently, without major issues with edge aliasing. Details are preserved at a satisfactory level, which makes lower-resolution materials look really solid on this TV. As a result, users can enjoy watching older content without obvious quality flaws.

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

LG UT8100, equipped with a 60 Hz display, will be especially suitable for people watching movies. The television offers the TruMotion system with de-judder effect adjustment, allowing users to customize the fluidity of the image – from more choppy to exceptionally smooth, reminiscent of a soap opera effect, depending on user preferences.

The issue of fluidity and sharpness of the image in motion 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 already defines its capabilities and makes it difficult to unequivocally recommend it to enthusiasts of dynamic sports broadcasts. During rapid camera movements, the image loses sharpness, and the panel itself also shows a slight tendency to blur, 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 independently decide on the final character of the motion – from a fully cinematic, slightly juddery image to achieving a very smooth, almost theatrical effect. It is a simple yet effective tool that allows users to tailor the viewing experience to their own preferences.

LG UT8100 offers basic features for gamers, such as ALLM and Game Bar, which makes access to settings easier. The TV also supports HGiG, which improves image quality in HDR games. Unfortunately, the lack of support for Dolby Vision and VRR limits the capabilities of the device, as does the 60 Hz panel, which excludes support for 120 Hz resolution. This model will be more suitable 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 package 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 completed by 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 easily supports high refresh rate signals of 120 Hz, but at lower resolutions – 1080p and 1440p. This is fantastic news for console owners who know full well how rarely games run in native 4K at a full 120 frames per second. The ability to choose between higher resolution and doubled smoothness is therefore an extremely sensible compromise.

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