LG OLED C6H (TANDEM OLED) vs Samsung M80H

And the biggest advantage of the Tandem OLED panel is most obvious with HDR. The C6H's brightness is simply very high and, in our measurements across most film scenes, hovered around 1,900 to 2,300 nits. That's the kind of level at which bright highlights, the sun or small light sources can look truly spectacular. The scene that impressed us most was the fifth scene from the film The Meg. It's particularly demanding for OLEDs because almost the entire screen is extremely bright. Even so, the C6H reached about 1,650 nits in that scene. By comparison, the standard C6 with a classic WOLED panel managed roughly 600 to 700 nits at the same point. So we're talking about more than double the brightness, and in places the difference approaches three times as much. And that's probably the best example of what Tandem OLED delivers. It's not just a higher score on a small test window. The C6H can maintain very high brightness even when much more of the screen is illuminated. That gives HDR a much wider dynamic range, and in this respect the C6H is considerably closer to flagship OLEDs than to typical mid-range models.

Colours

Tandem OLED also brings improvements in colour. DCI-P3 coverage remains virtually complete at around 99%, while in the much wider BT.2020 colour space we measured about 82–83%. That's roughly 7 percentage points more than the standard C6. In everyday viewing this won't be a difference you notice in every scene, because most films don't use such a wide palette. However, when very highly saturated colours appear, the C6H has noticeably greater capability, especially with reds. Reds benefit the most, becoming deeper and more saturated. It's still not at the level of the best QD-OLED panels or SQD TVs, but for a WOLED panel the result is really very good.

The M80H is not one of the brightest TVs. Its peak brightness is around 350 nits, and we saw similar results across most of our test scenes. That's not enough to achieve truly striking HDR, as bright highlights lack punch and the overall image is a little too dim. In practice, HDR on the M80H feels more like well-presented SDR than noticeably more dynamic material with a wide brightness range. The picture can still look fine, but it's hard to point to strong highlights, clearly bright light sources, or an effect that immediately sets HDR apart from ordinary content.

Colours

One of the M80H's stronger points is its colours. The TV uses a PFS filter in the backlight, which lets it display a much wider colour gamut than a standard LCD without filters. Our measurements confirm this – the M80H covers about 96% of the DCI-P3 gamut and 72% of BT.2020. Those are very good results, which allow colours to be richly saturated. Samsung's positioning here is interesting. The M80H isn't part of the QLED family, even though in terms of colour it is practically on par with models carrying that badge. From an image quality point of view that doesn't make much difference – the colours are simply good.

Right out of the box the LG C6 is pretty well set up, especially if you select Filmmaker mode. In SDR content the white balance is good, although as brightness increases it starts to lack red slightly. This makes the picture a bit cooler, but not enough to be very noticeable during normal viewing. More is going on in the luminance response. Gamma is a bit low and instead of holding at 2.4 it sits closer to 2.1–2.2 across a large part of the range. In practice the C6 slightly brightens midtones. Shadows are therefore more readable, but the image loses a little depth compared with how it should look in a dark room.

In HDR the situation is a bit more interesting. The start of the grayscale looks very good, but from around 20–30% brightness the white balance starts to drift more strongly. As brightness increases red builds up and blue becomes noticeably lacking. In the brightest parts the difference is already significant and also affects the reproduction of some colours. The EOTF curve itself is handled quite well across most of the range. The C6 only has a tendency to slightly brighten the picture, which we've already seen in our film comparisons. The biggest deviation appears around the brightest sections where the TV starts to adapt the signal to the panel's capabilities.

So the factory Filmmaker setting in HDR is not perfect, but overall performs well. The biggest room for improvement is the white balance, especially at high brightness.

Filmmaker Mode is pretty well set up out of the box, though it’s not perfect. In SDR material the most noticeable issue is an excess of red in the white balance, which makes the picture look a little warmer than it should. HDR content has a similar character. As for brightness response, in SDR the gamma stays close to the target value across most of the range. Small deviations are mainly visible in darker areas, which are in places slightly too dim. In HDR the very darkest details are slightly lifted, while from around 65% brightness the image starts to be gently darkened. This largely results from the way the TV controls its brightness. Overall, Filmmaker Mode looks good straight out of the box, but the picture can still be improved.

LG TVs have long responded very well to calibration, and the C6 is no exception. After adjustment, the white balance was set almost perfectly, and most colour errors fell to values below 3, often around 2. In practice this means very accurate colour reproduction in both SDR and HDR. An interesting detail only showed up with the HDR luminance response. On a classic EOTF chart everything looks almost perfect and at first glance it would be hard to fault. Only when we measured the TV’s behaviour using filters based on real film scenes did it emerge that the C6 has a slight tendency to artificially boost image brightness.

It isn’t a huge difference and many people may even see it as a positive, since HDR looks a bit more punchy. From the point of view of fidelity to the source material it’s not ideal, though — some scenes are simply a touch brighter than the filmmaker intended. Interestingly, this is quite atypical for LG. In previous generations, this brand’s TVs usually stuck very closely to the reference picture characteristics after calibration. With the C6 we’re still very close to the standard, but that subtle boost in brightness can indeed be noticed in movies and TV shows.

After calibration the M80H performs very well, especially with everyday SDR content. Regular TV, YouTube and movies watched without HDR can look very good on it. After adjusting the white balance the errors are small, though you can sometimes still see the TV tends to push the most saturated reds too far. You can also improve the picture in HDR and correct its main faults, but it doesn't reach the level of more expensive models. Samsung quite heavily restricts colour adjustment options in HDR, so in many areas we have to accept what the TV offers out of the box. Calibration can improve some parameters, but we can't change the M80H's overall picture character.

Here the LG C6 has taken a really big step forward. The TV uses the same processor found in the flagship G6, and in terms of image processing the two models are very similar. That's a big plus, because in this area LG's processor this year performs excellently. The 'Smooth Gradation' function works especially well. With heavily compressed material it can effectively hide unsightly tonal banding and artefacts that often appear, for example, in lower-quality streaming. It's best left on the 'Low' setting. That way the improvement is clear, and the TV doesn't yet start to blur fine details. Higher levels smooth the picture more, but can begin to remove some of the natural texture of objects on screen. Upscaling itself also performs very well. Lower-resolution content is properly sharpened, edges look clean, and the processor quite effectively reconstructs fine details. In this respect the C6 is already really close to LG's top TVs and the differences compared with the G6 are small.

Although the M80H is positioned fairly low in Samsung’s line-up, the maker equipped it with one of its stronger processors, the NQ4 AI Gen2. The same chipset is used in Neo QLED TVs and the higher‑ranked S85H OLED. That’s good news, because the processor handles improving weaker sources really well. Upscaling is its strongest suit. Low‑resolution material is displayed properly and edges don’t look overly jagged. The TV won’t of course create details that aren’t in the source, but regular broadcast TV and older recordings look decent on it. One drawback is overscan, i.e. edge cropping, which can’t be completely turned off. The feature that smooths tonal transitions, the so‑called noise reduction, also works well. The processor can effectively reduce visible signs of heavy compression, but it doesn’t do so without side effects. At higher settings it can smooth the picture too much, remove some fine detail and even eliminate film grain. For that reason we recommend using this feature mainly for material that genuinely suffers from heavy compression and posterisation.

The C6H with a Tandem OLED panel can also run at a refresh rate of up to 165 Hz. PC gamers will get the most out of that, of course, because with consoles, films or sport we're still looking at a maximum of 120 Hz. The panel itself performs excellently in motion. OLED pixels respond almost instantly, so even with fast-moving objects you don't see the usual trailing. The picture stays clean both when watching sport and in fast-paced games.

If you prioritise smoothness over motion clarity, TruMotion is available. LG lets you adjust two parameters separately. De-Judder mainly works with films and series shot at 24 fps and reduces their characteristic judder. De-Blur is intended for 50/60 fps content, so it's mainly useful when watching sport or TV.

The M80H performs very well for watching sport and for gaming. The TV is equipped with a panel offering a refresh rate of up to 144 Hz at 4K, and when the resolution is reduced to Full HD it can handle up to 240 Hz. That second option will be used mainly by PC gamers.

The panel also handles 120 Hz content well, which matters especially for console gaming. A high refresh rate is also useful when watching sport, and motion blur is relatively low. That's important because VA panels are not known for the best performance in this area. On the M80H, fast-moving objects do not produce a very noticeable blur.

The C6H offers virtually a full gaming feature set. On consoles you can easily use 4K at 120 Hz, while PC users can push the refresh rate up to 165 Hz. The TV also supports VRR from 40 to 165 Hz, ALLM and a correct implementation of HGiG. Dolby Vision is available in game mode too, which remains a big plus for Xbox owners. All the key info can be seen in the Game Bar, which provides quick access to VRR settings and the current signal parameters. The tandem OLED doesn’t change the actual feature set for gamers, but with such high panel brightness HDR games can look even more impressive. Functionally, the C6H is simply a very complete TV for consoles and PC.

The M80H could be a very good choice for gamers on a slightly smaller budget. In terms of features it offers pretty much the same as Samsung’s much more expensive TVs. All three HDMI inputs support HDMI 2.1, so even if one is taken by a soundbar connected via eARC there’s still room for a PC and consoles. There’s also VRR up to 144 Hz in 4K and up to 240 Hz in Full HD. Samsung has correctly implemented HGiG as well, so after performing HDR calibration on the console games are properly matched to the screen’s capabilities. That won’t make the M80H any brighter, but at least it won’t unnecessarily wash out the brightest parts of the image. On top of that there’s a Game Bar for quick access to key settings and a Gaming Hub that lets you play in the cloud without a console. The M80H also includes Game Motion Plus, which generates extra frames and improves the smoothness of games running at 30 or 60 fps. Input lag then increases to around 59 ms, but is still about one third of what you’d see with typical motion smoothing on other manufacturers’ TVs. We wouldn’t really recommend it for online multiplayer, but it can work very well in slower‑paced titles.