LG OLED C6H (TANDEM OLED) vs Hisense UR8S

And it is with HDR that the Tandem OLED panel shows its greatest advantage. The C6H’s brightness is simply very high and in our measurements it hovered around 1900–2300 nits in most film scenes. That’s already a level at which bright highlights, the sun or small light sources can look truly spectacular. The biggest impression, however, was made by the fifth scene from the film The Meg. It is exceptionally demanding for OLEDs because almost the entire screen is very bright. Even so, the C6H reached about 1650 nits in that scene. By comparison, the regular C6 with a classic WOLED panel recorded around 600–700 nits at the same point. So we’re talking about more than double the brightness, and in places the difference even approaches three times. And that is probably the best example of what Tandem OLED delivers here. It’s not just a higher result on a small test patch. The C6H can maintain very high brightness even when much more of the screen is lit. As a result HDR has significantly greater dynamism, and in this respect the C6H is much closer to flagship OLEDs than to typical mid-range models.

Colours

Tandem OLED also brings an improvement in colours. DCI-P3 coverage remains practically complete at about 99%, while in the much wider BT.2020 colour space we measured around 82–83%. That’s roughly seven percentage points more than the regular C6. In everyday use this won’t be a difference visible in every scene, because most films do not use such a wide gamut. However, when very highly saturated colours appear, the C6H already has noticeably greater capability, especially in reds. Reds benefit the most, becoming deeper and more saturated. This still isn’t at the level of the best QD-OLED panels or SQD TVs, but for a WOLED panel the performance is really very good.

UR8S is a slightly higher-end Mini-LED, so you could expect a lot in terms of brightness. And indeed, on a synthetic test pattern peak brightness reached around 2200 nits. That’s a very good result, but as always what’s much more important is what the TV does in normal film scenes. Here the results are a bit more uneven. In bright scenes, where there’s a lot of light on screen, the UR8S can deliver really strong HDR. Brightness then reaches about 1500 nits, so the image is very intense and has plenty of punch. It’s worse with small bright elements on a dark background. The TV clearly dims them to keep good blacks and to prevent excessive bloom. As a result things like single stars or tiny reflections can be only around 200 nits. And here HDR is no longer as impressive. So you can see that the local dimming algorithm works effectively, but it also has its cost: sometimes it simply sacrifices the brightness of small details in favour of contrast.

Colours

With RGB Mini-LED TVs colours should be judged a little differently than usual. If we look solely at the panel’s native capabilities, the UR8S performs excellently. We measured around 94% coverage of BT.2020 and practically full DCI-P3. These are among the highest values currently found in LCD TVs and this is where the potential of the RGB backlight is most obvious. The problem is that this potential is not always realised in real scenes. When we ran the same measurements on test patterns with a film background applied, saturation of some colours began to fall noticeably. Individual zones are not always able to control the three RGB components so precisely when the scene becomes more complex. This is most visible with blue and magenta. On simple test patterns they can look very strong, but in more demanding scenes samples of those colours visibly shrink. So the UR8S’s capabilities are enormous, it’s just that the TV cannot fully make use of them in every scene.

Straight out of the box the LG C6 is fairly well set up, especially if you select the Filmmaker mode. In SDR content the white balance is decent, although as brightness increases it shows a slight deficiency in red. The image therefore becomes a little cooler, but not enough for the difference to be very noticeable during normal viewing. More is happening in the brightness response. Gamma is a bit low and, instead of holding at 2.4, it sits closer to 2.1–2.2 across much of the range. In practice the C6 slightly brightens midtones. Shadow detail is therefore more readable, but the picture loses some depth compared with how it should look in a darkened room.

In HDR the situation is a bit more interesting. The lower end of the greyscale performs very well, but from roughly 20–30% brightness the white balance starts to drift increasingly. As brightness rises there is more red, while blue becomes noticeably deficient. In the brightest scenes the difference is already substantial and also affects the reproduction of some colours. The EOTF itself is, however, fairly well tracked across most of the range. The C6 merely tends to slightly brighten the image, which we already saw in our film comparisons. The largest deviation appears in the very brightest areas, where the TV begins to adapt the signal to the panel’s capabilities.

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

For assessing the out-of-the-box colours we used Filmmaker mode, which is intended to show an image that is as close as possible to how the material was prepared. Looking at the white balance alone, the UR8S performs quite well. There is no strong tint that immediately jumps out, although as brightness increases a little too much blue and red start to appear, with a simultaneous shortfall of green. Colour errors therefore show up in measurements, but the image itself does not look bad. We have far greater reservations about how the UR8S manages picture brightness. In SDR the gamma sits around 1.9–2.0 for most of the range instead of the target 2.4. In practice this simply means the picture is too bright, especially in the midtones. Shadows are lifted too much, causing the image to lose some depth. A similar tendency is visible in HDR. The EOTF curve is above the reference value for a large part of its range, so the UR8S again brightens the image more than it should. This is not due to a lack of brightness — the TV has plenty — but to the way it manages that brightness. As a result, HDR content can look very striking, but not always precisely as it should.

LG TVs have long been very receptive to calibration and the C6 is no exception. After adjustment the white balance could be set almost perfectly, and most colour errors fell below 3, often even down to around 2. In practice this means very accurate colour reproduction in both SDR and HDR. An interesting detail only emerged when we looked at the HDR luminance response. On a classic EOTF plot everything looks almost ideal and at first glance it would be hard to find fault. Only when we measured the TV's behaviour on filters based on real film scenes did it become apparent that the C6 has a slight tendency to artificially boost image brightness.

It is not a huge difference and many people may even welcome it because HDR looks a bit more striking as a result. From the point of view of fidelity to the source material this is not ideal behaviour though – some scenes are simply a touch brighter than the filmmaker intended. Interestingly, this is rather unusual for LG. In previous generations the brand's TVs typically stuck closely to the reference picture characteristic after calibration. With the C6 we are still very close to the standard, but this subtle brightness 'boost' can indeed be noticed in films and series.

Hisense provides plenty of calibration options and, in SDR, these can yield a very good result. After calibration, the white balance is practically even across the entire range, and colour errors fall to very low values. The UR8S can be adjusted very precisely here. HDR is somewhat different. The white balance itself can also be noticeably improved, although at the highest brightness levels larger deviations begin to appear. The most interesting aspect, however, is the behaviour of the EOTF curve. Even after it has been correctly set on test patterns, the UR8S still tends to interpret brightness in its own way when watching films. Depending on the scene, parts of the image are slightly brightened while others are dimmed relative to how they should appear. This shows that the algorithms controlling the local dimming have a significant influence on the final image. Calibration therefore allows colours to be improved very effectively, 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 considerable plus, because this year's LG processor excels in that area. The "Smooth Gradation" function works particularly well. With heavily compressed footage it can effectively hide ugly banding and artefacts that often occur, for instance in lower-quality streaming. It's best to leave it on the "Low" setting. Then the improvement is noticeable, while the TV does not yet start to blur fine detail. Higher levels smooth the picture more, but can already remove some of the natural texture of objects on screen. Upscaling itself also performs very well. Lower-resolution material is sharpened correctly, edges look clean, and the processor quite effectively reconstructs fine detail. In this respect the C6 is already very close to LG's best TVs and the differences compared with the G6 are small.

A big plus of the UR8S is the 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 lower-quality content. The feature responsible for this effect works effectively without overprocessing the picture. Even on the medium setting it can noticeably reduce visible banding and unevenness without heavily blurring details. Upscaling itself also performs very well. Lower-resolution content is displayed cleanly, edges look natural, and the image is not overly sharpened. The UR8S simply copes very well with a weaker signal, and in this respect it is one of its most notable strengths.

The C6H with a Tandem OLED panel can also operate at refresh rates of up to 165 Hz. PC gamers will naturally get the most out of this, because for consoles, films or sport we're still looking at a maximum of 120 Hz. The panel itself is excellent when it comes to motion. OLED pixels respond virtually instantly, so even with fast-moving objects you don't see the typical motion blur. The picture remains clean whether you're watching sport or playing 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 helps reduce the judder that's characteristic of them. De-Blur, meanwhile, is intended for 50/60 fps content, so it's particularly useful when watching sport or television.

The UR8S is equipped with a panel with a native 180 Hz refresh rate, so right from the start it offers excellent motion handling. The panel itself performs really well here, although some limitations typical of VA panels are still visible. Motion blur is relatively minor for this type of screen, but with faster motion (especially on darker backgrounds) it can still be noticed, particularly when compared with the same image on OLED TVs.

The C6H offers practically the full suite of gaming features. 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 proper implementation of HGiG. Dolby Vision is also available in game mode, which remains a major advantage for Xbox owners. All key information can be viewed in the Game Bar, which provides quick access to VRR settings and the current signal’s parameters. The OLED implementation therefore does not alter the feature set available to gamers, but with such high panel brightness HDR games can make an even stronger impression. Functionally, the C6H is simply a very complete TV for console and PC gaming.

In terms of gamer features the UR8S performs really well. The TV supports practically everything you can expect from a modern console or PC display. It offers ALLM, VRR and 4K at 120 Hz. There is also Dolby Vision in Game Mode, so when using, for example, the Xbox Series X you do not have to give up that HDR format. PC gamers get even more options. The panel can run at 4K at 180 Hz, and dropping to Full HD can raise the refresh rate to as much as 330 Hz. There is also a Game Bar that lets you quickly check key information and change gaming-related settings. The only clear omission is a correct implementation of HGiG. With it enabled the TV still alters HDR brightness mapping, so we do not get the effect intended by that standard. Aside from that, the UR8S is very well prepared for both consoles and a powerful PC.