May 29, 2015

4K-ing Hell


Disclaimer: For the sake of this article and making the numbers slightly less mind-bending, I’m going to refer to all QHD, UHD and C4K (anything above 1080p really) resolutions as 4K, which is kind of lying, but then the joke in the title wouldn’t work very well.

It’s official, we’re now in a new pixel count race between manufacturers. Soon you’ll wander into your local branch of Currys, only to be confronted by flashing signs from all the huge TV manufacturers, trying to sell you their latest super-high resolution glowing boxes. But should you, the consumer, care even the slightest bit about extra pixels? In short: hell no. I could just leave the blog here and allow you to get on with your day, but that’s just not how I roll.

“So, Chris”, I hear you say, “why shouldn’t I care?” Well the reason is actually really simple, for home consumption, you simply can’t tell the difference between 1080p and content at higher resolutions. Unless you happen to have a full cinema screen in your 2 bed flat, you sit within 2 ¾ inches of your TV, or you prefer viewing your content with the aid of some binoculars, it is physically impossible to tell the difference. The pixel density is already so high that our eyes simply can’t distinguish each individual pixel, so by adding more pixels into the mix we’re pointlessly wasting data. Don’t believe me? A rather fine chap called Carlton Bale wrote this amazing, albeit rather techie, article covering the topic.

What winds me up is that the extra data could be used in far better ways, like by increasing colour depth (which would be hugely noticeable, even at SD resolutions) or by simply using the increased bit rate to reduce any compression artefacts.


But anyway, I’m getting carried away, I could talk about what else winds me up about the current generation of TVs for quite some time, but I’m talking to creators, so there is something else I want to talk about. (CNET have a rather grand article covering most of the other problems with 4K UHD TVs, if you’re interested though.)

So what does 4K mean for creators? Well I’m going to start by saying that I shoot everything I can in 4K. Sure it means that file sizes are huge and you need a computer with the power of an imploding star to cut it, but it gives you amazing flexibility in post. Crucially, though I shoot in 4K, I edit in a 1080p workspace. This give me the power to crop in and out of the shot, to a degree, without any loss of quality (unless you’re pixel peeping and looking for the slightly more pronounced noise produced by the sensor). This means you can do all manners of groovy things like excessive motion stabilisation, or simply faking a close up by cropping, here’s an example using Fawn’s face (sorry it’s the only one I had available).

Here’s the wide:


Now as if by magic, we’re now worryingly close to Fawn’s face (again, apologies):


There are a few really really really really important points I’d like to make though. This new fangled extra resolution may give you the power to crop and tidy up things, but don’t use it as an excuse to get lazy during the actual shoot. I’ve caught myself saying on multiple occasions “eh, it’s fine I’ll fix it in post”; when you know that there’s some flex it’s easy to slip into bad habits. Crucially, if you shoot poorly to start with, forcing you to crop, it means that if at some point you actually do want to use the footage at its native resolution, you can’t.

Also, never shoot in a higher than necessary resolution if it has adverse effects on the image quality. At the end of the day, the numbers themselves are not really what matters, the story the image itself tells is far more important. That leads me rather handily onto a point that I struggled to get a strong grasp on for a long time: you could have the prettiest video in the world, but the content is always more important. For tips on stories, content and development, check out this series of blog entries from Jesse.

So in summary: “4K, pointless at home, but an awesome tool for creators.”

4K-ing hell indeed.