TCL P755 vs Haier K85F

TCL P755 provides average HDR effect quality. The maximum brightness of the television is slightly below 300 nits. Such brightness limits the intensity of bright areas in HDR content. In practice, this means that bright elements may not be sufficiently pronounced, which affects the overall impression of contrast. However, the television offers a wide coverage of the DCI P3 colour gamut, reaching around 93%. As a result, colours are vibrant and saturated, significantly improving colour reproduction quality in HDR content. Despite the limited brightness, the wide colour range allows for richer and more realistic shades.

Let’s now turn to one of the hottest topics in the world of televisions, namely 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 avoid this model at all costs. The main problem is its very low peak brightness, which during our tests barely reached 250 nits. To give you a better idea of what that means – such a value is fine for watching standard SDR content, but it is absolutely insufficient to showcase any real benefits of HDR. The image simply lacks the "power" to generate bright, striking highlights. All our measurements and tests on specialist patterns only confirmed this. As if that weren't enough, the television also struggles with colour reproduction. In this budget build, we won't find any technologies to expand the colour palette, such as quantum dot layers (marketed as "QLED"). As a result, the coverage of the DCI-P3 colour space, which is crucial for HDR materials, is only around 80%. In practice, this means that the image will not only be dark but also devoid of the vibrant, saturated colours that the director wanted to show us.

The colour reproduction in the P755 in "Movie" mode, although it is the best factory setting, leaves much to be desired. The biggest problem is the white balance, where the graph clearly shows a spike in red and a drop in green. This leads to a shift in colours towards red, making the colours on the screen less natural and potentially looking incorrect, especially in scenes with a white or neutral background. This is confirmed by the "Colour Checker" test, which reveals that the colours are indeed skewed towards red, affecting the realism of the image and reducing the perception of colour depth. In terms of contrast, the gamma chart analysis shows considerable fluctuations, particularly in dark areas of the image, where values drop below the optimal level of 2.4. This results in darker areas being displayed brighter than they should be. Additionally, the EOTF curve, responsible for brightness reproduction, is slightly above the reference curve. The graph shows a slight boost in brightness to around 50%, followed by only a minor decrease. This leads to excessive brightness enhancement in the mid-tones of the image and may result in loss of detail and distortion in brighter scenes.

Well, how does the television perform with colours straight out of the box, without any interference from our side? The Haier K85F offers a full range of picture modes, such as Dynamic and Eco, but for anyone who wants to watch films according to the creators' intentions, only one really matters: Film mode. That is where we focused our tests, and unfortunately, its name has little to do with reality. The picture in the factory settings is very far from what we could call cinematic fidelity and requires numerous adjustments. Let's start with the white balance, which has a noticeable deficiency of red. In practice, this means that the entire image has a cool, bluish tint. The situation is even worse regarding brightness management, namely the gamma curve (for SDR) and EOTF (for HDR). Their graph resembles a real rollercoaster, which has a disastrous impact on the viewing experience. This results in unnatural dimming of SDR content, causing details in shadows to be lost, and in the case of HDR – excessive brightness, which further exacerbates the issue of clipping. Such a combination, namely too cool white combined with chaotic brightness and excessive blue saturation, results in significant errors in colour reproduction. Our measurements on the specialist ColorChecker chart revealed errors (Delta E) regularly reaching and exceeding values of 8-9. Put simply, errors above the threshold of 3 are already easily noticeable to the naked eye, so such a result means that the colours on the screen are simply heavily distorted.

After calibration, the colour reproduction on the television improves significantly when it comes to SDR content. The colour curves are now close to the ideal value, and the gamma is more stable. Although the drop at the beginning of the graph to value is still present, the overall accuracy of colour reproduction is much better. The "Colour Checker" test shows that most colour samples have errors below level 2, indicating improved colour fidelity. A few deviations are present, but generally, the colours are now more realistic and consistent with reality.

Calibration also brings improvement in HDR content. The white balance has been improved, resulting in a more natural colour reproduction. The EOTF curve, although now closer to the reference curve, still shows a slight boost in brightness at the beginning of the graph. This leads to minor distortions in very bright scenes, but the overall tonal quality and detail have been enhanced. Dynamic tone mapping works more effectively, improving image quality in bright areas and retaining more detail.

Although the device's picture does not achieve complete perfection, calibration brings significant improvement. After adjusting the settings, the television presents itself much better, offering a more realistic and accurate colour reproduction in SDR and HDR content. While some shortcomings can still be noticed, calibration effectively eliminates many previous issues, ensuring better image quality and more natural colours.

Well, is there anything that can be done about this picture? Can professional calibration save the situation? The answer is both yes and no. It must be clearly stated that there are certain limitations we cannot overcome. The constraints of the design itself, meaning simply a poor panel and its narrow colour coverage, make it impossible to expect a reasonable HDR effect – we won't mislead you on that. The biggest beneficiary of our adjustments is undoubtedly the SDR mode, and it is indeed for watching such content, after calibration, that this television starts to make sense. We managed to somewhat tame the white balance. Although the television only offers basic 2-point adjustment (rather than precise 20-point), so it's not perfect, we successfully eliminated that unpleasant, cold "chill" in the picture. Above all, however, we noted 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 television can finally display images without artificially dimming or brightening them. The conclusion is simple: even with such a cheap television, professional adjustment of the settings can achieve a lot and extract the maximum potential from it.

The "Gradual Smoothing" function works quite well, effectively eliminating visible boundaries between different shades of the same colour. Thanks to it, tonal transitions are smoother. Unfortunately, this function is not available in HDR mode, which may affect the quality of tonal gradations in higher dynamic range materials.

When it comes to image scaling, the television does not perform at its best. There are noticeable edge cuts, particularly evident on the figure of the model and the branches of trees. The blurring of details in these areas affects the overall sharpness of the image. This may be noticeable when watching content in a lower resolution. Moreover, SD quality images are displayed with slight cropping at the top as well as the bottom.

Let's move on to digital processing and image scaling, specifically how the Haier K85F handles lower resolution signals, such as those from standard television. Right from the start, we encounter an extremely annoying and completely incomprehensible issue – overscan that is enabled by default. This means that the television artificially enlarges the image, cropping its edges, and this happens on every source, even 1080p. To see the full frame, you have to dig through the screen settings each time and manually switch the format to "expand to 16:9". It's a detail, but it's devilishly frustrating. The very act of scaling content to 4K resolution can be summed up in one word: acceptable. And that's about it. The image processor does not strip details from the picture, nor does it generate jagged edges or other artifacts. It simply does its job, without any fireworks. It's alright, but nothing more. However, the biggest and most noticeable shortcoming in the digital processing section is the absence of a smooth tonal transition feature. This is an algorithm that could significantly reduce the annoying banding effect we mentioned earlier. Unfortunately, the manufacturer did not provide such a solution, condemning us to watch the imperfections of the panel and low-quality materials in full view.

The television offers decent, although not perfect, results in terms of motion fluidity. For films, the television features a “Flicker Reduction” function that allows for motion fluidity adjustment on a scale from 1 to 10. With this option, we can customise the appearance of the image to a cinematic or more theatrical preference (with a slower or faster pace).

The matrix in the K85F model operates at a native refresh rate of 60 Hz, which right from the start sets certain expectations regarding image fluidity. However, we must admit that we were very positively surprised when we found two separate sliders for motion control in the settings menu: one labelled as "Motion Blur Reduction" and the other "De-Judder". Such generosity in this price segment is an absolute rarity, as typically manufacturers offer at most one shared option. Unfortunately, our enthusiasm waned as quickly as it appeared. It soon became clear why Haier was so "generous" – the slider responsible for motion blur reduction is simply a dummy. Its adjustment brings absolutely no visible effect on the screen, so only one of the two options works.

The device offers a range of features useful for gamers, such as ALLM (Auto Low Latency Mode), VRR (Variable Refresh Rate), Dolby Vision for gamers, and Game Bar. ALLM automatically switches the television to low latency mode, significantly improving response to commands from the controller and minimising input lag. VRR synchronises the screen refresh rate with the number of frames generated by the console, eliminating screen tearing and providing smoother gameplay. Dolby Vision for gamers enhances picture quality, offering better colour and contrast reproduction in games that support this format. The Game Bar feature allows quick access to game settings and monitoring of key parameters such as reaction time.

However, the television has certain limitations. The 60 Hz panel prevents the display of higher refresh rate signals at various resolutions, which may affect the smoothness of the image in dynamic games. Additionally, the lack of support for G-Sync technology for PC may impact gameplay quality on a computer. It is also worth noting that the HGiG mode, which aims to improve picture quality in HDR games, does not function correctly in this model, negatively affecting the visual experience in HDR-supported games.

Let's move on to features for gamers, although we must emphasise at the outset that this is more of a proposal for the "casual" ones. 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 ploy. What good is a modern port if 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 deprives the HDMI 2.1 port of its most significant advantage. It's a shame. (That’s why we mark it as HDMI 2.0 in our tests). Another curious peculiarity is the television's reaction to attempts to calibrate HDR from the console level. Changes to brightness settings cause very unnatural image behaviour, which might suggest an incorrect implementation of the HGiG standard. To be honest, however, one shouldn't worry too much about this, because as we've mentioned numerous times, we simply do not recommend using any HDR content on this screen. However, to avoid being too negative, 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. While it works within a very modest range of 48-60 Hz, its mere presence is commendable. As a result, the image in games can experience less "tearing," which significantly improves the gaming experience.