In my ongoing adventure of “trying to work out if 4K is any good or not”, I finally got round to doing a direct comparison: some scenes from The Punisher episode one, which I compared in 4K with Dolby Vision (through my TV’s Netflix app) to 1080p (through my Amazon Fire TV Stick).
And holy moly if I didn’t really see the difference.
In 4K, The Punisher’s got gritty, grainy visuals. In 1080p, that quality all but disappeared, just smudged away. And the colours… I watched in 4K first, and during a particularly dark scene I tried to note how distinguishable different colours and shades were in shadowy areas. I needn’t have bothered: in 1080p it was all just black. So, in conclusion, the difference in both areas (resolution and colour range) was, to be honest, considerably more pronounced than I was expecting.
Now, a few caveats. This conspicuous a change is undoubtedly due in part to how much bandwidth Netflix bothers to use, and therefore how much compression is being applied. It seems that for 4K they devote about three to four times more bandwidth than for 1080p (and even that’s about half what a Blu-ray goes at). This may not have affected the colours, but it likely explains why the 1080p stream lacked so much of the fine detail seen at 4K.
Also, there’s always the potential that my TV’s settings were affecting things. HDR and Dolby Vision use a dedicated set of picture settings, which have to be setup separately from those used for regular playback. I’ve optimised both sets as best I can, but there’s always the possibility I did one better than the other. There’s also the fact that I was using different devices. Maybe the Fire TV Stick is just less good at streaming Netflix than my TV’s app? (If I could force the Netflix app to play in lower quality then I’d’ve done the entire comparison there for fairness, but I don’t think that’s possible.)
Finally, to drag a different series into the debate, I also watched Stranger Things 2 in UHD with Dolby Vision. Most of the time it looked fine, but every once in a while the colours in a shot would look completely screwy — usually too blown out, like someone had whacked the brightness up to silly levels, sometimes erasing detail in the process. Now, what Dolby Vision does is adjust the picture settings on a shot-by-shot basis to optimise every individual moment (rather than just use a blanket setting for the whole movie, which is what standard HDR does). Presumably that’s why the picture went funny on individual shots rather than for whole scenes. I’m far from an expert on these things, but I believe part of how Dolby Vision does this is to do with metadata, and apparently metadata can just go missing. Perhaps this is what happened. On the other hand, I went back and checked some of the most egregious moments on a different day and they retained the same problem. Who knows what was going on, then, but it’s obviously less than ideal. (If the same thing happened during The Punisher, I didn’t notice it.)
So, after all that, I’m still not 100% convinced about UHD and HDR… but I can’t deny there was a marked improvement when comparing The Punisher, particularly during very dark scenes. Heck, even if the difference is just a fluke of how I’ve set up my TV, it proves that paying for the 4K option on a Netflix subscription is worth it. But purchasing a 4K Blu-ray player, which I’d also need to be region free, along with the prospect of having to rebuy some films again… that’s a lotta dough.
I should probably do a Netflix UHD to 1080p Blu-ray comparison, really. Next time…