LG OLED G5 vs TCL C9K

LG G5 with the new Tandem OLED matrix brings the biggest change in terms of the brightness of the television. And it's substantial. This is truly an astronomically bright OLED. In every scene tested – whether it was point lights or full-screen whites from the film The Meg – the brightness on the G5 exceeded 2000 nits. Just a year ago, such values on an OLED were simply unimaginable. And here we are – the G5 is approaching, and at times even surpassing, the best Mini-LEDs on the market. A new feature of the Tandem OLED matrix is also the expanded colour gamut – and here the LG G5 performs almost perfectly. DCI-P3 reaches a full 100%, and BT.2020 is maintained at around 83%. These are some of the highest values currently available on the market – it's hard to find any other television that comes close to such results, unless we are talking about the best displays with QD-OLED panels. The G5 has nearly reference-quality HDR – both in terms of brightness and colour saturation. This is an OLED that can truly shine – and not just figuratively.

As we mentioned with black and contrast – the C9K makes a huge impression in synthetic tests. Our measurements showed that on a screen 10% filled with white, the television is capable of squeezing out... 4000 nits of brightness! It sounds cosmic, but – and here unfortunately the pattern repeats – the numbers say one thing, and practice another. In real film scenes, the situation looks different. In the best case, when the light effects occupy a large part of the image and the local dimming algorithm doesn't have to think too hard about what to do with thousands of zones – the result is really quite good. At that point, the C9K can reach about 1500 nits, which provides a pleasant, intense flash and can indeed make a positive impression.

The problem begins with smaller elements – such as stars in the sky, the moon, or individual reflections. That's when the proverbial cat comes out of the bag: the algorithms are not yet refined, and brightness drops even to 400–500 nits. This is a huge difference compared to the potential of 4000 nits that we saw in laboratory tests. Why does this happen? Most likely, the television tries to protect the black and minimise the halo effect around bright objects. Unfortunately, this comes at the cost of details – some of the intricate details simply disappear, and the scene loses its nature.

Our test unit, the LG G5, struggled with certain issues in the factory Filmmaker mode. And although most people might have found the picture acceptable, we knew that this television was capable of much more. This mode had a clear excess of blue tint in the white balance, resulting in a significantly cooled image – particularly in HDR modes, where there was additionally a lack of red. The picture appeared cold, and its sharpness was artificially boosted and unnatural. Another significant issue was the brightness characteristics. In SDR content, the situation wasn't the worst, aside from a slight dimming of the entire image. However, it performed much worse in HDR materials – due to improper brightness management, the smallest details could completely disappear from the image, while larger, bright elements looked overexposed and lacking in gradation. Fortunately, the G5 supports calibration using 3D LUT (a tool for professionals for colour calibration), so we decided to make use of its professional capabilities and see what it could really do. Because although it wasn't tragic even before calibration, the potential of this television definitely deserved more.

For colour tests, we once again reached for the Filmmaker mode – a new feature in TCL televisions for 2025. And although the direction itself is a step in the right direction, the execution leaves much to be desired. The white balance in SDR content turned out to be too warm – there was an excess of red. Conversely, in HDR, it swung in the opposite direction: the image became excessively blue. The Colour Checker test revealed quite a few colour inaccuracies that were noticeable to the naked eye. An even bigger problem turned out to be what we mentioned above – managing brightness. Regardless of whether we were watching SDR or HDR content, the image had a tendency to blow out the entire scene, giving it an unnatural, almost grotesque character. Therefore, it is hard to call this a 'director’s mode' – because the director surely has never seen such an image.

After performing the calibration process using professional tools, we can confidently state that the LG G5 offers nearly reference-quality image. Most of the errors related to white balance and the ColorChecker test are below a value of 2, which is a phenomenal result, practically imperceptible to the human eye. And while one could still nitpick that in HDR films the television still has a tendency to slightly dim the smallest elements of the image, in practice this does not negatively affect the overall impression. Kudos to LG, as once again they provide the user with enormous possibilities for adjusting their display – and this, combined with the very good parameters of the panel itself, results in an image that is truly hard to beat.

After calibration, we finally managed to tame the white balance – and it immediately translated into a more natural image. Colours finally started to look as they should, and the overall presentation was incomparably better than with the factory settings. In other words – it’s worth taking a moment to improve this, as the gain is really significant. The gamma responsible for managing brightness was also brought under control in SDR content, and the effect was more than satisfactory. Unfortunately, when we switched on the HDR material, the situation quickly became complicated. No matter how we set the local dimming, the television had a tendency to do what it pleased with the image – either overexposing the whole picture or dimming the darkest parts too much. Just like we saw in the scene from the film Billy Lynn. Colour-wise, the improvement after calibration makes a great impression, but managing brightness in HDR remains the Achilles' heel of the C9K and constitutes a technological limitation.

Upscaling and digital image processing in the LG G5 are quite impressive. The television handles lower quality content very well, especially when the "Smooth Gradation" feature is set to a low level. In this mode, it effectively removes unwanted artifacts and issues with visible tonal transitions. It may also slightly smooth out some desirable details, such as the subtle texture of clothing or skin, but importantly – it does not remove film grain, so it's difficult to speak of a serious compromise here. This is one of those options that is definitely worth enabling.

The G5 also performs well with upscaling, which improves the quality of older materials. The test image with the model looked really solid – slight jaggedness was visible, but that's an effect that cannot be completely avoided. Additionally, there were no problems with overscan, which – contrary to appearances – is not at all obvious, even in 2025.

The digital image processing in TCL C9K is rather mediocre. The tone transition smoothing feature is supposedly present, but activating it hardly makes any difference – colour banding is still visible, and it can inadvertently highlight elements we would prefer to hide, such as textures of objects. Fortunately, it does not remove film grain, but that's scant consolation considering the effects are still poor. Thus, it's hard to recommend using this option.

On the other hand, image scaling performs significantly better. Lower quality materials look quite decent – characters and backgrounds are represented clearly, although of course, with sources like 576p, the limitations of the physics cannot be disguised. Sometimes, there's characteristic aliasing of objects, but that's due to the source itself, not the algorithm. A plus for the fact that there are no overscan issues – the image is neither artificially cropped nor enlarged.

The motion smoothness on the LG G5 is simply phenomenal. The television is equipped with a 165 Hz refresh rate panel, and this, combined with the instant response time of the OLED matrix, delivers incredible results. The image does not tear or stutter like on traditional LCD televisions. Like most LG models, the G5 is equipped with a motion smoother, which can be useful when watching films – we are, of course, referring to the TruMotion mode. With the "De-Blur" and "De-Judder" sliders, we can adjust the smoothness of older materials according to our own preferences, whether we want to maintain the characteristic film stuttering or lean towards a more fluid, television-like effect.

Similar to the C8K, the C9K is also a really fast television – both figuratively and literally. On board, we have a 4K panel with a refresh rate of 144 Hz, and at lower resolutions, the panel can even ramp up to 288 Hz. Such speed translates into practice – while watching sports or playing games, the picture looks very smooth and clear. Additionally, in films, we get an extra motion smoothing feature called Motion Clarity, which allows you to adjust the smoothness to your own preferences – from the cinematic "stuttering" of frames to nearly theatrical smoothness.

Features for gamers? Perfect. That should be sufficient for you to know what level we are dealing with here. The G5 is a television designed with gamers in mind, so we will find literally everything you could expect from a gaming screen. There is a Game Bar, there is support for high resolutions with high refresh rates – that is, 4K at 120 Hz, and even more, as the panel has a refresh rate of 165 Hz (which PC gamers will benefit from). The television supports variable refresh rate (VRR), automatic low latency mode (ALLM), and also correctly handles HDR in games thanks to the HGiG function. All of this adds up to one of the best sets of gaming features available on the market. Well done, LG.

For gaming, the TCL C9K is a complete tool. Here we have two (out of four) HDMI 2.1 ports with full bandwidth of 48 Gbps, so all the key technologies work: VRR (Variable Refresh Rate) and ALLM (Auto Low Latency Mode). Additionally, the manufacturer has included a really intuitive Game Bar, which allows you to quickly check the most important parameters and adjust settings without rummaging through the menu. Also worth noting is TCL's policy – the television does not shy away from any HDR formats, even in game mode. Whether it's HGiG or Dolby Vision for the Xbox Series S/X console – everything works as it should, giving the player a wide range of freedom.