TCL C8K is a really bright television. In synthetic conditions – that is, during tests with brightness charts – it was able to achieve even 3500 nits peak brightness in movie mode. That's an impressive result and brings the C8K close to the market leaders, at least when it comes to panel brightness. More importantly – these aren't just numbers on paper. In films with a lot of bright scenes, such as Life of Pi or The Meg, the brightness clearly exceeds 1000 nits, providing a true sense of HDR effect. The picture in those moments looks very dynamic, colors are saturated thanks to excellent coverage of the color palette, and the lights are – spot on and intense. Exactly how it should be.
However, this doesn’t mean that everything is perfect. Just like in contrast tests, here too, in more demanding scenes, compromises appear. In sequences with very fine light elements – such as stars in the night sky or reflections in dark rooms – the local dimming algorithm can… get confused. Instead of bringing those details up, the television sometimes decides to dim them significantly – down to around 300 nits – to maintain deep blacks. On one hand, this is quite a sensible approach (better deep black than a grey/navy blue screen), but on the other – there may be moments when certain elements of the picture become difficult to see or even disappear into darkness.
TEST UPDATE (20/08/2025): The brightness control algorithm in this model is quite problematic – attempting to calibrate the picture so that it doesn’t drastically overexpose the brightest scenes results in unnatural shifts: improvement in one part of the image results in deterioration in another. The television may achieve slightly higher readings in brightness measurements, but in practice, this comes with a heavily overexposed image that looks very unnatural!
For the record, we provide brightness values without this adjustment:
1463 nits
640 nits
1368 nits
468 nits
1025 nits
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.