TCL C855 vs Philips OLED770

The TCL C855 delivers a highly varied HDR effect. At times, the television truly excels, while at other moments, it appears reminiscent of a low-end model equipped with FALD backlighting. Inconsistency is frequently found with this brand, so it didn’t come as a surprise. The first and last scenes, which feature large light elements, are nothing short of spectacular, boasting brightness levels of 1470 and 1820 nits, respectively. Such brightness can make viewers squint their eyes, allowing them to feel the extraordinary dynamism of the scene. It genuinely immerses the audience, creating a sensation of being inside the movie itself. However, the situation shifts dramatically when small or subtle elements with high luminance appear against a dark background. In these instances, the TCL C855 significantly reduces brightness to levels as low as 240 nits to mitigate halo effects. This reduction is disappointing, as it can make the movie appear as if it was not filmed in HDR. Despite these shortcomings, the HDR effect on the TCL C855 enhances the viewing experience during dynamic scenes, making it feel more engaging and allowing the viewer to feel part of the action. Even with smaller high-luminance elements, the television retains details without excessive dimming. Additionally, the TCL C855 adjusts image brightness according to scenes with rich detail, further enhancing viewing comfort.

The Philips OLED770 does not attempt to compete with the brightest OLEDs on the market, and it would actually be hard to expect that, as it is the lowest model in Philips's series for 2025. In our measurements, it achieved a maximum brightness of about 700 nits, which allows for enjoyment of HDR effects in scenes where light appears point-wise – for example, in the flash of headlights or a starry sky. In such moments, the picture can truly impress. However, it is different when there are more bright elements on the screen. The television, like many cheaper OLEDs, limits brightness in those cases, and the entire picture noticeably dims. This was best seen in a scene from the movie The Meg, where the sun rises behind an oil rig – at that point, the brightness dropped to about 250 nits, nearly three times less. The HDR effect remains visually pleasing, but it is worth being aware that this model performs best in scenes with less intense light. Fortunately, the OLED770 has an ace up its sleeve – the coverage of the DCI-P3 color palette is as high as 99%, so colors in movies and games are saturated and very close to what the creator intended to convey.

The best factory mode for the TCL C855 is the "Film" setting, and all our tests were conducted using this mode. However, like many predefined modes, it has flaws that should be addressed to achieve an image closer to the producer's original vision. In our examination of the colour characteristics for both SDR and HDR materials, issues were found.

Focusing first on SDR content, there is a noticeable dominance of green in the white balance, which leads to an unpleasant greenish tint across the entire image. The gamma chart, crucial for image contrast, shows a significant deviation from the reference line marked at 2.4. Initially, there is a pronounced spike in the measured value, resulting in an over-contrasted image where details can merge into a dark blob. This condition persists for nearly 20% of the chart before it dips below the reference line, causing the image to brighten and resulting in a substantial drop in contrast.

In HDR materials, the factory mode performs somewhat better; the white balance appears more balanced overall, although the green tint resurfaces in the latter half of the spectrum. When we look at the Electro-Optical Transfer Function (EOTF) curve—unlike gamma, which reflects contrast—we identify two main errors: the darkest scenes are too dark, while the brightest ones become overexposed. This discrepancy was evident in our review of the scene from the movie "Pan," further illustrating the TCL C855's HDR performance issues.

The first measurements already show that the factory settings of the Philips OLED770 have a lot to improve even in Filmmaker mode. The white balance chart clearly shows a lack of blue, which gives the image a slightly yellowish tint. In practice, the white is not snow-white, but leans towards warmer hues – which some may even like, but from the accuracy perspective, this is a deviation from the norm. The gamma, on the other hand, tends to be on the darker side – the average value is about 2.6 instead of the reference 2.4. In the mid-tones, the image appears muted and more saturated, which may look too "filmic," but takes away some naturalness. However, the biggest issues can be seen in color reproduction. The average error is relatively high, and some colors – especially shades of gray – clearly deviate from what should be seen. In everyday viewing, this means that sometimes colors may look less natural than we would wish.

TCL, like most manufacturers, offers advanced calibration tools within its televisions. These include both 2-point and 20-point adjustments for grayscale, as well as a comprehensive colour management system. As a result, we achieved impressive results in SDR materials, bringing the image significantly closer to the reference standard. We successfully eliminated both the green tint and the gamma issue, although a slight "kink" at the very beginning of the gamma curve still persists.

In contrast, the situation with HDR materials was less favourable, as the TCL C855 did not allow for precise modelling. We were only able to make minor adjustments to the EOTF curve while significantly enhancing the overall colour accuracy. This limitation suggests that while calibration tools are effective, they may require further refinement for optimal HDR performance.

Philips OLED770 has shown signs from the beginning that it houses significant potential, but it was difficult to fully see this in the factory settings. The image was sometimes too warm, and some colors seemed to have lost their naturalness along the way. However, calibration revealed that it is a television very receptive to adjustments – it reacted to every correction and almost immediately unveiled another layer of its capabilities. The white balance was successfully set both in SDR and HDR, eliminating the yellowish glow and presenting a neutral, clear white. Gamma stabilized closer to perfection, allowing midtones to regain their naturalness, and shadows no longer appeared artificially darkened, possibly even with a slight brightening effect. The effect was obvious... Movies are watched with greater ease; the image has cinematic depth, but without the feeling that something is exaggeratedly darkened. However, the most interesting part was the work on colors. Out of the box, the errors were not dramatic but slightly noticeable – skin tones were sometimes too warm, and gray didn’t always have the shade we expected. After calibration, the error values dropped to around 2, and in many cases even below 1. This is a level significantly lower than the threshold of perception for the human eye. In other words, after correction, the colors finally “clicked” into place. Looking at the screen, we had the impression that the television had begun to speak with a full voice. Like an instrument that has finally been well-tuned.

Once again, we will take a look at the function of smoothing tonal transitions, but this time also image scaling. The latter is particularly important when watching materials of lower quality, such as some television programs or older films. We will focus on the function responsible for tonal transitions. Interestingly, just like in the scenes from the previous test where it performed excellently and smoothed out practically all the inconsistencies, here it had issues. Using the menu responsible for the operation of this function, we found that no setting—even the strongest—was helpful.

Image scaling in TCL C855 is defined as one of the best we have had the opportunity to test so far. The image is sharp, but in a way that could be described as natural to our eye. Even small, fine branches do not have jagged edges, and there is no white halo around figures, a characteristic of weaker scaling systems.

The problem of the previously mentioned color connections can largely be mitigated by the "distortion reduction" feature, which is an algorithm for smoothing tonal transitions in Philips TVs. It works best at a low setting—effectively eliminating unwanted color bands while not introducing strange artifacts or losing image detail. It's one of those features that is truly worth keeping switched on.

The issue with upscaling is somewhat less favorable. The image from a lower resolution can be too soft, while at the same time, distinctive "jaggies" appear in certain areas. The impression is that the algorithm is trying to reconcile two contradictory directions—smoothing and sharpening—and ultimately hasn't found the golden mean. As a consolation, it's worth noting that the television has no issues with overscan, meaning it doesn't cut off the edges of the image, which sometimes happens with other competing models.

The maximum refresh rate you can set on the TCL C855 is 144 Hz. Naturally, this is only possible after connecting the TCL C855 TV to a very powerful PC. Otherwise, we will be operating at a maximum refresh rate of 120 Hz, which is recommended if we want to watch primarily sports or materials with a lot of motion dynamics. For those who require high image fluidity, the manufacturer has implemented a multi-stage motion smoother. It is divided into two separate sliders which control the sharpness of moving images (Motion Blur Reduction) and flicker (Flicker Reduction). Both sliders can be adjusted from 0 to 10, with each level affecting the degree of fluidity, so everyone can find their sweet spot. We present a setting that allows for slight smoothing without the soap opera effect. The matrix of the TCL C855 features a very good response time. This is particularly important since VA panels often struggle with the so-called ghosting effect, where a black halo can be observed behind a fast-moving object. where a black halo can be observed behind a fast-moving object.

The issue of the panel in the Philips OLED770 is not entirely straightforward. The manufacturer claims a 120 Hz panel, but our measurements showed that the screen can accept a 4K signal even at 144 Hz. This sounds like great news – because who wouldn't want an extra mode for PC gaming at this price? However, the reality turned out to be more complex. With 120 Hz materials, the television behaves like most OLEDs – the picture is absolutely clear, with no trace of ghosting or blurring, making it ideal for both fast-paced games and sports broadcasts. The problem arises only at 144 Hz. Unlike models with official support for that frequency, here we observe the phenomenon of so-called frame skipping. This means that the television is unable to display all frames – some of them are skipped, causing the motion to lose fluidity, and double outlines appear on the screen. The effect resembles the operation of the BFI function, which Philips does not offer in this model anyway.

The TCL C855 TV has fully-featured HDMI 2.1 ports, boasting a full bandwidth of 48 Gb/s. During our testing, we confirmed the seamless operation of all functions included in this connection standard. As highlighted, all checkboxes are illuminated in green, a feature that will undoubtedly be appreciated by gamers, whether on consoles or those using the TV as a computer monitor. Additionally, the TCL C855 supports both AMD FreeSync and NVIDIA's G-Sync, which can be easily activated in the graphics card settings. Those with powerful configurations can feed a 144 Hz signal to the C855, which handles this effortlessly. It is also worth noting the implementation of the HGIG mode, which can be excessively bright due to the shortcomings of the "Game" mode, making proper configuration on the screen challenging. Fortunately, the TV excels with the Dolby Vision format.

TCL, as one of the pioneering manufacturers, has equipped its televisions with a special GameBar, allowing for extensive adjustment of settings "on the fly" without the need to exit the game. This feature includes options like an additional crosshair grid, black level correction, and settings designed for individuals with disabilities. The image showcases the next generation of this solution.

In summary, the TCL C855 TV is an ideal choice for those seeking a screen for all forms of electronic gaming. With comprehensive features supporting such entertainment, it provides an extremely engaging experience. It is also important to emphasise that it maintains very low input lag, regardless of the selected settings, including when using the Dolby Vision HDR format.

If someone is looking for a gaming TV, the Philips OLED770 is a candidate that's hard to ignore. The mere fact that we have an OLED here provides a great starting point – perfect blacks and infinite contrast make evening sessions in atmospheric games look like they’ve been pulled straight from the cinema. On top of that, there’s the Ambilight system, which features LEDs on the back of the TV that extend the image onto the wall behind the screen. The effect is such that even regular gameplay in FIFA can look like a small spectacle, and in horror games, the atmosphere becomes really intense. On the technical side, it’s pretty good as well. The Philips OLED770 supports Variable Refresh Rate (VRR) up to 120 Hz, has an automatic low latency mode for gamers (ALLM), and if someone is using an Xbox Series X, they can also count on Dolby Vision support in games. You just need to know that in this mode, input lag is slightly higher than standard, although still at an acceptable level. As a bonus, we get the “Game Bar” panel, which is a special tool strip for gamers. It's not the most conveniently designed solution, but it allows you to check key parameters without leaving the game. In total, this presents a picture of a TV that on one hand has all the most important gaming features, and on the other can add something unique – Ambilight. And it’s this mix of technology and visual effect that makes the OLED770 one of the better screens for gaming in a home environment.