TCL P7K / P79K vs LG MRGB85B

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%.

LG MRGB85 offers moderate brightness. On test patterns it reaches around 700 nits, which is a decent result in itself. In real movie scenes, however, values are lower and most often fall in the 400 to 600 nits range. Bright, wide shots look best. In scenes with large areas of black the TV noticeably reduces luminance, attempting to keep contrast as high as possible. The HDR effect is therefore visible, but it is far from the level offered by more advanced Mini-LED designs. Particularly in darker parts of films, the limitations of the edge-lit backlight and imprecise local dimming become apparent again.

HDR colours

A much stronger suit of the MRGB85 is its colour. The TV covers around 95% of the DCI-P3 colour space and 74% of BT.2020, so HDR content can look vivid and impressive. Colours are well saturated, and the difference compared with basic LCD TVs is clearly noticeable. It is worth noting, however, that this is not a classic RGB backlight, where each of the three primary colours is generated by a separate diode. Red is produced by a PFS phosphor, which expands the palette and achieves more saturated red tones. This solution performs well for colour reproduction, but it does not change the limitations of the local dimming. The diodes are not driven independently in the way the series name might suggest... so it turns out that Mini RGB is not the same as Mini-LED RGB!

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.

We tested the TV in Filmmaker Mode because, of the available presets, it produced the image closest to reference. The out-of-the-box colour reproduction wasn’t perfect, though. The biggest deviations were in the white balance, with too much red and not enough blue in the image, so the overall picture shifted noticeably towards warmer tones. Whites took on a slightly yellowish tint, and skin tones and bright areas didn’t always look natural. It wasn’t a fault that ruined the viewing experience, but in a direct comparison with the same panel after calibration the difference was clearly visible.

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.

Calibration primarily corrected the white balance and removed the previously noticeable warm cast. After the correction, whites no longer had a yellow tint and colours became more neutral and natural. The biggest improvement was seen in SDR material, where the picture looked even and much closer to the reference. A similar effect was achieved in HDR. After calibration the image became more controlled, although not all of the TV’s limitations could be eliminated. The main issue remained intense reds, which were not always reproduced with sufficient precision. In practice the MRGB85 handles everyday SDR content very well, but in more demanding HDR material its limitations are still clearly visible.

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.

Upscaling and digital image processing perform quite well in the LG MRGB85. The Alpha 8 AI 4K Gen7 processor efficiently upscales lower-resolution material, and you can easily turn off overscan regardless of the source. The TV also handles compression artefacts well. The "Smooth Gradation" function can effectively reduce visible banding and tonal unevenness, but it isn't always precise. At higher settings it can also smooth out fine details, such as the texture of materials. A plus is that it doesn't remove film grain. The safest option is the "Low" or "Medium" setting, which offers the best compromise between artefact reduction and preserving detail.

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.

The LG MRGB85 is fitted with a VA panel with a native 144 Hz refresh rate, so its motion handling is very good. The TV easily handles 120 Hz content from consoles and higher refresh rates when connected to a PC. That matters not only for gaming but also when watching sport, where camera motion is noticeably smoother than on basic 60 Hz panels. There’s also the TruMotion system, which lets you set the level of motion smoothing yourself. You can keep a more cinematic motion or increase smoothness, which works well for live sports and TV programmes. The adjustment range is wide, so you can easily tailor the motion smoothing to your own preferences.

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.

When it comes to gaming, the LG MRGB85 performs by far the best. The manufacturer hasn’t skimped on the kit and has essentially carried over the full suite of features from pricier TVs into this model. You get three HDMI 2.1 ports with full 48 Gb/s bandwidth. Each supports 4K 120 Hz from a console, and when connected to a PC also 4K 144 Hz. So you don’t need to worry which port to plug your console or PC into, as they all offer the same set of capabilities.

On board you’ll also find VRR, AMD FreeSync Premium, NVIDIA G-Sync Compatible, ALLM and HGiG. Dolby Vision Gaming is included too, allowing supported games to use high refresh rates and dynamic HDR simultaneously on Xbox. Rounding it off is Game Optimizer, a handy in-game menu. Without leaving the game you can change the picture profile, brighten shadow detail or check the current frame rate. In terms of gaming features, the MRGB85 therefore offers almost the same as significantly more expensive LG models.