TCL P7K / P79K vs Haier K85F

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%.

Now let's move on to one of the hottest topics in the world of televisions, which is the quality of HDR effect. In the case of the Haier K85F model, we must unfortunately make it clear: if you are looking for equipment to watch content in a wide dynamic range, you should steer clear of this model. The main issue is its very low peak brightness, which during our tests barely reached 250 nits. To give you a better idea of what this means – such a value is okay for watching standard SDR materials, but it is absolutely insufficient to show any real benefits of HDR. The image simply lacks the "power" to generate bright, striking bursts. All our measurements and tests on specialist patterns only confirmed this. As if that weren't enough, the television also struggles with color reproduction. In this budget model, we won't find any technologies that expand the color palette, such as quantum dot layers (known in marketing as "QLED"). As a result, the coverage of the DCI-P3 color space, which is crucial for HDR materials, is only about 80%. In practice, this means that the image will not only be dark but also devoid of vibrant, saturated colors that the director wanted to show us.

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.

Well, how does the television perform with colors straight from the factory, without any intervention from our side? The Haier K85F offers a full range of picture modes, such as Dynamic or Eco, but for anyone who wants to watch movies according to the creators' intentions, only one really matters: Film mode. This is the mode we focused our tests on, and unfortunately, its name has little to do with reality. The picture in the factory settings is far from what we could call cinematic fidelity and requires many adjustments. Let's start with the white balance, which has a clear lack of red color. In practice, this means that the whole picture has a cool, bluish tint. The situation is even worse when it comes to brightness management, specifically gamma curves (for SDR) and EOTF (for HDR). Their graph resembles a real rollercoaster, which has a disastrous effect on the viewing experience. This results in unnatural dimming of SDR content, causing details in the shadows to get lost, and in the case of HDR – excessive brightness, which further exacerbates the issue of highlights. This combination, meaning too cool white combined with chaotic brightness and excessive blue color saturation, causes enormous errors in color reproduction. Our measurements on a specialized ColorChecker chart showed errors (Delta E) regularly reaching and exceeding values of 8-9. In simpler terms: errors above the threshold of 3 are easily noticeable to the naked eye, so such a result means that the colors on the screen are simply heavily distorted.

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.

Well, is there anything we can do about this image? Can professional calibration save the situation? The answer is: both yes and no. It must be clearly stated that there are certain things we cannot overcome. The limitations of the construction itself, namely a poor panel and its narrow color coverage, mean that you can forget about achieving meaningful HDR – we won’t sugarcoat it for you. The biggest beneficiary of our adjustments is undoubtedly the SDR mode, and it is precisely for watching such content, after calibration, that this television begins to make sense. We managed to tame the white balance in our own way. Although the TV only offers basic 2-point adjustment (instead of precise 20-point), it’s not perfect, but we successfully eliminated that unpleasant, cold "chill" in the image. Above all, however, we recorded a significant improvement in brightness management. The gamma curve, which previously resembled a rollercoaster, looks like an almost perfectly straight line after calibration. This is a sign that the TV can finally display images without artificially dimming or brightening them. The conclusion is simple: even in the case of such a cheap television, professional adjustment of the settings can achieve a lot and draw out its maximum potential.

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.

Let's move on to digital processing and image scaling, that is, how the Haier K85F handles lower resolution signals, for example, from standard television. Right from the start, we encounter an extremely annoying and completely incomprehensible issue – the overscan feature is enabled by default. This means that the television artificially enlarges the image, cropping its edges, and this occurs on every source, even 1080p. To see the full frame, you have to dig into the screen settings every time and manually switch the format to "stretch to 16:9." It's a detail, but incredibly frustrating. The scaling of content to 4K resolution can be described in one word: acceptable. And that's basically it. The image processor does not strip the image of details, nor does it generate jagged edges or other artifacts. It simply does its job, without any fireworks. It's fine, but nothing more. The biggest and most noticeable shortcoming in the digital processing section is the absence of a banding smoothing function. This is an algorithm that could significantly reduce the annoying banding effect we mentioned earlier. Unfortunately, the manufacturer did not implement such a solution, condemning us to watch the imperfections of the panel and low-quality materials in all their glory.

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 panel in the K85F model operates at a native refresh rate of 60 Hz, which already sets certain expectations for smoothness of the image right from the start. However, we must admit that we were very positively surprised when we found not one, but two separate sliders for motion control in the settings menu: one labeled "Blur Reduction" and the other "De-Judder." Such generosity in this price segment is an absolute rarity, as usually manufacturers offer at most one common option. Unfortunately, our enthusiasm quickly dwindled as fast as it appeared. It soon became clear why Haier was so "generous" – the slider responsible for blur reduction is simply a dummy. Moving it does not produce any visible effect on the screen; thus, only one of the two options actually works.

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.

Let's move on to the features for gamers, although we must point out right away that this is more of a proposal for "casual" players. The manufacturer boasts in the specifications about the presence of HDMI 2.1 ports, which looks impressive on paper, but in reality, it is largely a marketing gimmick. What good is a modern port when the heart of the television is a panel with a refresh rate of 60 Hz? It physically cannot display a signal at 120 frames per second, even at lower resolutions, which takes away HDMI 2.1's most important advantage. That's a shame. (That’s why we mark it as HDMI 2.0 ports in our tests). Another oddity is the television's response to attempts to calibrate HDR from the console. Changes in brightness settings cause very unnatural behavior of the image, which might suggest an incorrect implementation of the HGiG standard. To be honest, however, you shouldn't worry too much about this, because as we have mentioned multiple times, we simply do not recommend using any HDR content on this screen. However, to make it not so bitter, the Haier K85F also has two significant and unexpected advantages. The first is the presence of ALLM, or Auto Low Latency Mode, which switches the television to low latency mode as soon as it detects a connected console. The second, even bigger surprise is support for VRR, or Variable Refresh Rate. Although it works in a very modest range of 48-60 Hz, its very presence is commendable. Thanks to this, the image in games can stutter less, which truly improves the gaming experience.