LG OLED C6H (TANDEM OLED) vs Hisense UR8S

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.

UR8S is a higher-end Mini-LED, so you could expect plenty of brightness. Indeed, on a synthetic test pattern peak brightness reached about 2200 nits. That’s a very good result, but as always what the TV does in normal film scenes matters much more. Here the results are a bit more mixed. In bright scenes with lots of light on screen, the UR8S can deliver very strong HDR. Brightness then gets up to around 1500 nits, so the image is very intense and has a lot of punch. It’s worse with small bright elements on a dark background. The TV noticeably dims them to preserve deep blacks and avoid excessive blooming. As a result, things like single stars or small specular highlights can be only around 200 nits. And here HDR is no longer as impressive. So the local dimming algorithm works effectively, but it comes at a cost — sometimes it sacrifices the brightness of small details too much in favour of contrast.

Colours

For RGB Mini-LED TVs, colours should be evaluated a little differently than usual. If we look only at the panel’s capabilities, the UR8S performs excellently. We measured about 94% coverage of BT.2020 and virtually full DCI-P3. Those are among the highest figures currently seen in LCD TVs, and this is where the potential of the RGB backlight is most apparent. The problem is that this potential isn’t always used in real scenes. When we ran the same measurements on patterns overlaid with a film-like background, saturation of some colours started to fall noticeably. Individual zones can’t always control the three RGB components with the same precision when the scene becomes more complex. It’s most noticeable with blue and magenta. On simple test patches they can look very strong, but in tougher scenes samples of those colours clearly shrink. In other words, the UR8S has huge potential, but the TV can’t always take full advantage of it in every scene.

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.

For evaluating the factory colours we used Filmmaker mode, which is supposed to show the image as close as possible to how the content was prepared. And if you look at the white balance alone, the UR8S performs quite well. There’s no strong tint that immediately jumps out, although as brightness increases a bit too much blue and red start to appear, with a corresponding lack of green. Colour errors are therefore visible in measurements, but the image itself doesn’t look bad.

We have much bigger reservations about how the UR8S manages image brightness. In SDR the gamma stays around 1.9–2.0 for most of the range instead of the target 2.4. In practice this simply means the image is too bright, especially in the midtones. Shadows are lifted too much, so the picture loses some depth. A similar tendency is visible in HDR. The EOTF curve sits above the reference value for a large part of the range, so the UR8S again brightens the image more than it should. This isn’t a case of the TV lacking brightness, because it has plenty, but of how it manages that brightness. As a result, HDR material can look very striking, but not always exactly as it should.

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.

Hisense offers quite a lot of calibration options, and in SDR you can achieve a really good result with them. After adjustment the white balance is practically even across the whole range, and colour errors fall to very low values. The UR8S can be set very precisely here. HDR looks a little different. The white balance can also be noticeably improved, although at the highest brightness levels larger deviations start to appear. Most interesting, however, is the behaviour of the EOTF curve. Even after correctly setting it on test patterns, the UR8S can still interpret brightness in its own way when watching films. Depending on the scene, parts of the picture are slightly brightened and others darkened compared with how they should look. This shows that the algorithms controlling the backlight have quite a large influence on the final image. Calibration therefore allows colours to be improved very well, but we are not able to completely 'turn off' the way the UR8S manages brightness in HDR.

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.

The big plus of the UR8S is its use of the MediaTek Pentonic 800 processor, and digital image processing is one of this model’s stronger points. The TV handles smoothing tonal transitions very well, especially with poorer-quality material. The feature responsible for this effect works effectively without overprocessing the picture. Even on a medium setting it can noticeably reduce visible banding and artefacts without heavily blurring details. Upscaling itself also performs very well. Lower-resolution content is displayed cleanly, edges look natural, and the image isn’t over-sharpened. The UR8S simply copes very well with weaker signals, and in that respect it’s one of its clear strengths.

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 UR8S is equipped with a panel that has a native 180 Hz refresh rate, so right away it offers very strong potential for smooth motion. The panel itself performs really well, although some limitations typical of VA panels are still visible. Smearing is relatively low for this type of screen, but during faster motion, especially on darker backgrounds, it can still be noticed, particularly if you compare the same image to OLED TVs.

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.

In terms of gamer features the UR8S stacks up really well. The TV supports virtually everything you'd expect from a modern console or PC display. It has ALLM, VRR, and 4K at 120 Hz. There's also Dolby Vision in game mode, so when using, for example, an Xbox Series X you don't have to give up that HDR format. PC gamers get even more options. The panel can run at 4K and 180 Hz, and dropping to Full HD can push the refresh rate as high as 330 Hz. There's also a Game Bar that lets you quickly view key info and change gaming-related settings. The only real shortcoming is a proper implementation of HGiG. When enabled, the TV still interferes with HDR brightness mapping, so we don't get the effect intended by that standard. Apart from that, the UR8S is very well equipped for both consoles and a powerful PC.