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

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 LG G6 is currently one of the brightest OLEDs on the market. Its peak brightness reaches nearly 2500 nits, and best of all – this has a direct impact on real film scenes. The television flawlessly pulls out details in the bright parts 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's protection system (ABL). However, in real, varied film shots, this value still hovers around 2000 nits, which can be considered an outstanding result. The coverage of the color palette also deserves praise. The new 2nd generation Tandem OLED panel brought only a cosmetic change, but still an improvement. The DCI-P3 color gamut coverage reaches nearly 99.5%, while the ultra-wide BT.2020 is around 84%. These are very good results, although one must remember one thing: at extremely high brightness levels, the volume of colors will be lower than in QD-OLED panels from Samsung Display due to the use of a white sub-pixel (WOLED). However, in everyday content and most films, detecting this difference will be very difficult.

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.

We tested the LG G6 in the best factory mode for color fidelity, which is FILMMAKER MODE. For our test unit, this mode was fairly well-tuned right out of the box. In SDR content, the only thing we could nitpick was the white balance, which leaned towards warmer tones. As a result, the image could sometimes appear slightly yellowed; however, overall, it wasn't a bothersome issue. The G6 performed a bit worse with HDR content. There, we noticed too much blue component in the white balance. This caused the image to take on cooler shades, resulting in quite noticeable errors. As can be seen in our ColorChecker chart, colors were indeed shifting towards these cooler registers. Nevertheless, for factory settings, the television displayed a completely decent level. However, we know that OLED screens – especially those from LG – respond wonderfully to professional calibration, which is why we immediately proceeded with it.

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.

After conducting a professional calibration, we gained complete control over the panel, and we were able to adjust all parameters to nearly zero. We managed to perfectly tune the white balance, which made the factory-cool and warm tints disappear from the screen. The effects are clearly evident in the ColorChecker test – the average color reproduction errors dropped below the critical value of 1-2. And what does that mean? PERFECT colors, with no distortion whatsoever! However, from a reviewer's obligation, we must comment on how the LG G6 autonomously manipulates brightness, for which the EOTF curve is responsible. When we look at the standard synthetic graph, it may seem that the line is quite straight. The situation changes, however, when we turn on the measurement filter, which shows how the television interprets brightness in real, moving film scenes (EOTF in MOVIES). At that point, it becomes clear that some of the smallest fragments 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 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 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.

No matter what one may say about the G6's problems with near-black signal, it must be fairly acknowledged that it handles highly compressed material and lower resolution content brilliantly. All unwanted, ugly tonal transitions are effectively reduced here by the “Smooth Gradation” feature. On the “Low” setting, the algorithm operates flawlessly – effectively masking the artifacts resulting from strong compression, without destroying the sharpness and details in the frame. Higher levels of this feature indeed smooth the image even more, but they start to blur the real texture elements of objects, which is why we recommend keeping this slider at a low level. 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 respect, the G6 does not lag behind the world's best.

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.

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

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.

LG G6 is a true monster for gamers and one of the best-equipped TVs in this regard on the market. The manufacturer did not seek compromises and equipped 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 your PlayStation 5, Xbox Series X, or powerful PC into, you will extract the absolute maximum from them.

The TV supports a full suite of gaming technologies: from VRR (Variable Refresh Rate), through AMD FreeSync Premium Pro, to Nvidia G-Sync Compatible. Let's add to this the remarkably low, almost imperceptible input lag and a brilliantly functioning gamer panel (Game Optimizer), which allows you to continuously monitor the signal parameters. Gaming on this screen, with the perfect black of OLED and powerful refresh rates, is pure pleasure.