TCL P7K / P79K vs LG OLED G6 (G64LW, G66LS)

When turning to the assessment of HDR performance, we must be clear and without marketing embellishments: the P7K/P79K is not, and was never intended to be, a master in this field. The maximum peak brightness that this panel can generate hovers around a mere 300 nits. This represents a threshold, a kind of thin red line between what can be considered a barely satisfactory HDR signal and what is, in fact, 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 portions of the scenes rarely exceeded the ceiling of 200-250 nits. Thus, this is not a television that would allow content realised in a wide tonal range to spread its wings, and this must be openly admitted.

Unfortunately, the issue of colour reproduction is presented with equal restraint. Although the manufacturer positions this model within 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 colour gamut reaches only 86%. In the context of the market, this is at best an average result, as most devices that employ additional layers to expand the colour spectrum easily achieve values at a minimum level of 90-92%.

The LG G6 is currently one of the brightest OLEDs on the market. Its peak brightness reaches nearly 2500 nits, and what’s best – this has a direct impact on real film scenes. The television flawlessly extracts details in the bright areas of the image. And this is regardless of whether we are talking about very small points like stars in the sky or slightly larger elements on the screen. Naturally, with full-screen, uniformly white scenes, the brightness of the G6 decreases due to the panel protection system (ABL). However, in real, varied cinematic shots, this value still hovers around 2000 nits, which can be considered an outstanding result. The coverage of the colour palette also deserves praise. The new second-generation Tandem OLED panel only brought a cosmetic change but still an improvement. The coverage of the DCI-P3 palette reaches nearly 99.5%, whereas for the ultra-wide BT.2020, it is around 84%. These are very good results, although it’s worth remembering one thing: at extremely high brightness levels, the colour volume will be lower than in Samsung Display’s QD-OLED panels due to the use of a white sub-pixel (WOLED). However, in everyday content and most films, catching this difference will be very difficult.

Every accurate assessment of image quality must begin with selection of the most optimal factory mode. In the case of the tested model P7K/P79K, the choice was made without hesitation for the "Film" mode. It is this mode that presents an image closest to the intentions of the 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 has not escaped a few missteps. The most noticeable flaw turned out to be the not completely correctly set white balance. A slight dominance of the blue component gives the image a subtly cool, cold character, thus deviating from the exemplary neutrality that the director wanted to show us. The television performs much better in reproducing the greyscale in the standard dynamic range – the gamma curve is nearly exemplary. The only minor reservation could be made regarding 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 the TCL software, however, was interpreting the HDR signal, as illustrated by the course of the EOTF curve. The television follows its own, quite free path here – the darkest details are disproportionately brightened, after which there is a noticeable slowdown in the increase of brightness for midtones. Fortunately, most of these imperfections are software-related issues that can be eliminated. With this thought in mind, we began the process of professional calibration.

We tested the LG G6 in the best factory mode in terms of colour fidelity, namely FILMMAKER MODE. In the case of our test unit, this mode was quite well tuned straight out of the box. In SDR content, the only issue we could point out was the white balance, which tended to drift towards warmer tones. Consequently, the image could occasionally appear slightly yellowed; however, overall, this was not an bothersome problem. The G6 performed a bit worse with HDR content. There, we noted too much blue component in the white balance, which caused the image to take on cooler hues, resulting in fairly noticeable errors. As can be seen in our ColorChecker chart, the colours indeed drifted towards these cooler registers. Nevertheless, considering the factory settings, the television displayed a perfectly decent level. We do know, however, that OLED screens – particularly those from LG – respond excellently to professional calibration, which is why we immediately went ahead with it.

The calibration process turned out to be spot on, particularly in the context of standard dynamic range (SDR) content. We successfully mitigated the television's tendency to emphasize cool tones, restoring the whiteness to its natural neutrality. Moreover, precise adjustments allowed us to correct a slight error in the gamma curve, ensuring that the darkest parts of the image regained their proper depth, without any trace of unnatural brightness. The effects are measurable and impressive – in the ColorChecker test, the overwhelming majority of colour reproduction errors fell below the perceptual threshold, achieving a deltaE value of under 2. This is a result that pricier models would not be ashamed of. Unfortunately, when it comes to HDR content, we encounter a barrier in the form of the inherent limitations of the panel itself. And although we managed to bring the colours into line, the software's characteristics mean that the television still adapts brightness in its own way, as evidenced by the persistent, non-standard EOTF curve. In summary, calibration adds immense value, but one must be aware that it cannot overcome certain physical barriers. The slightly elevated black level, due to the lack of local dimming, along with limited peak brightness, means that HDR content may not always be able to showcase its full potential. This is simply not the primary task of this display; its true strength, especially after professional tuning, lies in the viewing of SDR material.

After professional calibration, we gained complete control over the panel, and we managed to align all parameters to nearly zero. We successfully calibrated the white balance perfectly, which eliminated the factory cool and warm tints from the screen. The effects are clear as day in the ColorChecker test – the average colour reproduction errors dropped below the critical value of 1-2. And what does that mean? PERFECT colours, without any distortion! However, as reviewers, we must point out here how the LG G6 arbitrarily manipulates brightness, for which the EOTF curve is responsible. When looking at the standard synthetic chart, it might seem that the line is quite straight. However, the situation changes when we turn on the measurement filter, which shows how the television interprets brightness in real, moving film scenes (EOTF in MOVIES). Then it becomes evident that some of the tiniest parts on the screen are slightly over-brightened by the algorithm. Of course, for the average viewer, such a deviation will be practically unnoticeable, but in the test of such an expensive screen, it is worth noting – especially since we are talking about a model that has huge aspirations to be named the best television of the year.

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 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 designs; however, in the price segment represented by the P7K/P79K, the results achieved are more than solid. The feature for smoothing tonal transitions performs particularly well, effectively eliminating posterisation, which are the characteristic bands often visible in highly compressed materials, for example, from the ChooseTV service. The algorithm adeptly removes unwanted gradients, which ultimately looks really good. The television also handles upscaling competently, which is the task of elevating low-resolution materials to 4K standard. The resulting image, although it may initially seem a bit too sharp, fortunately, is not a problem. The software allows for free adjustment of this parameter using a sharpness slider, making it easy to customise the final appearance to personal preferences.

Whatever one may say about the G6’s problems with near-black signal, it must be fairly acknowledged that it handles heavily compressed material and lower resolution content exceptionally well. All unwanted, unsightly tonal transitions are effectively reduced here by the "Smooth Gradation" feature. At the "Low" setting, the algorithm works flawlessly – effectively masking the artefacts resulting from strong compression without destroying the sharpness and details in the frame. Higher levels of this function do indeed smooth the image further, but they start to blur the real elements of object texture, which is why we recommend keeping this slider at a low setting. As for the upscaling to 4K, the processor does an excellent job – edge sharpness and detail reconstruction are at the highest level, and in this regard, the G6 does not fall behind the world leaders at all.

The issue of fluidity and sharpness of the image in motion is inextricably linked to a fundamental parameter of the matrix, and in the case of the TCL P7K/P79K, we are dealing with a panel with a native refresh rate of 60 Hz. This specification defines its capabilities from the outset and makes it difficult to unequivocally recommend it to enthusiasts of dynamic sports broadcasts. During fast camera movements, the image loses sharpness, and the panel also shows a slight tendency to smearing, 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 material recorded at 24 or 30 frames per second. Thanks to a dedicated slider, users can decide for themselves the final character of the motion – from maintaining a fully cinematic, slightly juddery image to achieving a very smooth, almost theatrical effect. It is a simple but effective tool that allows users to tailor the viewing experience to their own preferences.

LG G6 is an OLED television, so in the category of motion fluidity, it traditionally deserves the highest marks. The television supports very high refresh rates reaching up to 165 Hz in 4K resolution, but most importantly – on the screen, you will not notice any signs of blurring. The response time of the panel is almost instantaneous, ensuring that dynamic images remain perfectly sharp.

Although on paper the native 4K@60Hz panel might suggest that the TCL P7K/P79K is not a television tailored for gamers, the reality is 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 complemented 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 television easily supports a high refresh rate signal of 120 Hz but at lower resolutions – 1080p and 1440p. This is fantastic news for console owners, who know 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 passionate tournament players, for the casual or occasional console user, it offers a package of options that is hard to find among many competitors at this price.

The LG G6 is a true monster for gamers and one of the best-equipped televisions on the market in this regard. The manufacturer has not skimped on features, equipping this model with as many as four full HDMI 2.1 ports with a maximum bandwidth of 48 Gbps. This means that no matter which port you plug in your PlayStation 5, Xbox Series X, or powerful PC, you will get the absolute maximum performance from them.

The television supports a full set of gaming technologies: from VRR (Variable Refresh Rate) to AMD FreeSync Premium Pro, and even Nvidia G-Sync Compatible. On top of that, it offers remarkably low, nearly imperceptible input lag and an exceptionally well-functioning Game Optimizer panel, which allows you to monitor signal parameters in real time. Gaming on this screen, with the perfect black of OLED and impressive refresh rates, is pure pleasure.