LG OLED G5 vs TCL C9K

LG G5 with the new Tandem OLED panel brings the biggest change specifically in terms of the brightness of the television. And it’s quite impressive. This is truly an astronomically bright OLED. In every tested scene – whether it’s point lights or full-screen whites from the movie 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 comes close, and at times even surpasses the best Mini-LEDs on the market. A new feature of the Tandem OLED panel is the expanded color gamut coverage – and here the LG G5 performs almost perfectly. DCI-P3 achieves a full 100%, while BT.2020 maintains 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 color saturation. This is an OLED that can truly shine – and not just figuratively.

As we mentioned with black and contrast – the C9K can make 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 astronomical, but – and here, unfortunately, the pattern repeats – the numbers say one thing, and practice says another. In real movie scenes, the situation looks different. At best, when the light effects occupy a large part of the image and the local dimming algorithm does not have to think too hard about what to do with thousands of zones – the effect is really good. At that point, the C9K can reach around 1500 nits, which provides a pleasant, intense flash and can indeed make a positive impression.

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

Our test unit LG G5 struggled with some issues in the factory Filmmaker mode. And while the image might have seemed fine to most people, we knew that this TV was capable of much more. This mode had a clear excess blue tint in the white balance, resulting in a strong cooling of the image – particularly in HDR modes, where there was also a lack of red. The picture seemed cold, and its sharpness was artificially boosted and unnatural. Another significant issue was the brightness characteristic. 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, and larger, bright elements appeared overexposed and lacking gradation. Luckily, the G5 supports calibration using 3D LUT (a tool for professionals to calibrate colors), so we decided to take advantage of its professional background and see what it was really capable of. Because while it wasn't terrible even before calibration, the potential of this TV definitely deserved more.

For color tests, as always, we reached for the Filmmaker mode – a new feature in TCL TVs for 2025. And while 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. On the other hand, in HDR, it went in the opposite direction: the image became excessively blue. The Colour Checker test revealed quite a few color errors that were noticeable to the naked eye. An even bigger problem turned out to be what we mentioned above – brightness management. Regardless of whether we were watching SDR or HDR content, the image tended to blow out the entire scene, giving it an unnatural, even grotesque character. It's hard to call this a "director-created" mode – because the director has certainly never seen such an image.

After completing 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 the value of 2, which is a phenomenal result, practically imperceptible to the human eye. And while one could still criticize that in HDR films the television tends to slightly dim the smallest elements of the image, in practice, this does not negatively affect the overall impression. Hats off to LG, because once again they provide the user with enormous possibilities for adjusting their display – and this, combined with very good parameters of the panel itself, results in an image that is truly hard to surpass.

After calibration, we finally managed to tame the white balance – and it immediately translated into a more natural image. Colors finally started to look the way they should, and the overall presentation was incomparably better than in the factory settings. In other words – it’s worth taking a moment to improve this, as the gain is truly significant. The gamma responsible for managing brightness was also brought into order in SDR content, and the effect was more than satisfying. Unfortunately, when we turned on HDR materials, the situation quickly became complicated. No matter how we set the local dimming, the television had a tendency to do what it liked with the image – either it overexposed everything or dimmed the darkest parts too much. Exactly as we saw in the scene from the movie Billy Lynn. So, the color improvement after calibration makes a great impression, but brightness management in HDR remains the Achilles' heel of C9K and presents a certain technological limitation.

Upscaling and digital image processing in the LG G5 perform very well. The television handles lower quality content exceptionally, 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 desired details, such as the subtle texture of clothing or skin, but importantly – it does not remove film grain, so it’s hard to say there’s a serious compromise here. It’s one of those options that’s definitely worth enabling.

The G5 also does well with upscaling, which is improving the quality of older materials. The test image with the model looked really solid – slight edging was visible, but that’s an effect that can’t be completely avoided. Additionally, there were no issues with overscan, which – contrary to appearances – is not obvious, even in 2025.

Digital image processing in TCL C9K is quite mediocre. The tonal smoothing feature seems to be present, but turning it on practically changes nothing – color bands are still visible, and it can unintentionally highlight elements we would prefer to hide, such as textures of objects. Fortunately, it doesn’t remove film grain, but that’s small comfort since the effects are still poor. Therefore, it's hard to recommend using this option.

On the other hand, image scaling performs much better. Lower quality materials look quite decent – characters and backgrounds are presented clearly, although, of course, with sources at 576p, physics cannot be fooled. Sometimes, characteristic aliasing on objects appears, but that’s the fault of the source itself, not the algorithm. A plus for not having issues with overscan – the image is not artificially cropped or enlarged.

The motion fluidity on the LG G5 is simply phenomenal. The TV is equipped with a 165 Hz refresh rate panel, and this combined with the instantaneous response time of the OLED matrix delivers incredible results. The picture doesn’t stutter or smear like on classic LCD TVs. Like most LG models, the G5 features a motion smoother, which can be useful when watching movies – of course, we're talking about the TruMotion mode. With the “De-Blur” and “De-Judder” sliders, we can adjust the smoothness of older material according to our preferences, whether we want to preserve the characteristic film stutter or move towards a more fluid, television-like effect.

Like the C8K, the C9K is also a really fast television – both figuratively and literally. It features a 4K panel with a refresh rate of 144 Hz, and at lower resolutions, the display can even ramp up to 288 Hz. This speed translates into practice – when watching sports or playing games, the image looks very smooth and clear. Additionally, in films, we get an extra motion smoother called Motion Clarity, which allows us to adjust the fluidity to our own preferences – from the cinematic "judder" frame to almost theatrical smoothness.

Features for gamers? Perfect. That should be enough for you to know what level we are dealing with here. G5 is a television designed with gamers in mind, so we find literally everything one can expect from a gaming screen. There is Game Bar, support for high resolutions with high refresh rates – that is, 4K at 120 Hz, and even more, because the panel has a refresh rate of 165 Hz (which PC gamers will benefit from). The television supports variable refresh rates (VRR), automatic low latency mode (ALLM), and correctly supports HDR in games thanks to HGiG. 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 key technologies work: VRR (variable refresh rate) and ALLM (automatic low latency mode). Additionally, the manufacturer added a really intuitive Game Bar, which allows you to quickly preview the most important parameters and adjust settings without digging through the menu. Also, TCL's policy is a plus – the TV is not afraid of 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 wide freedom.