Every week, I like to choose one specific topic to discuss from the latest edition of DF Direct Weekly – and there’s certainly an embarrassment of riches to choose from in another vast episode. We sat down to film our 141th show the morning after The Game Awards, and despite the usual downplaying of expectations from Geoff Keighley, the ‘wurld prm’ears’ came thick and fast. For this blog though, it’s actually a supporter question that prompts this article. DF Supporter Julian Sniter asked us whether upscaling technologies like AMD’s FSR and Epic’s TSR are making it harder for us to ‘count pixels’ and ascertain native resolutions. The answer is yes, but the more verbose answer is that upscaling technologies have evolved at least twice since we first started image quality testing – and it’s more difficult now than ever.
It’s been a couple of years now since I made it a personal mission to downplay – if not eliminate completely – revealing the native rendering resolution of any given game. Back in the Xbox 360 and PlayStation 3 era, target resolution was typically 720p and upscaling from beneath that could have a significant impact on the image quality of any given game. However, moving into the PS4 Pro/Xbox One X era, the output resolution target moved to native 4K and a whole host of intriguing upscaling technologies came into play – the most popular being checkerboard rendering (as seen in the likes of Horizon Zero Dawn, Days Gone and many others) and temporal super-sampling/jittering (Marvel’s Spider-Man and For Honor being two great examples). We often refer to that latter tech as TAAU – a combination of upscaling and temporal anti-aliasing.
With a few obvious outliers (The Avengers used CBR on PS5, TAAU on Xbox), the direction of travel from developers was to favour TAAU and at that point, the argument to kill pixel counts once and for all seemed unassailable. Identifiable upscaling artefacts seemed to mostly disappear in favour of clarity: the higher the internal resolution, the less blurry the image was. And the more pixels you upscaled, the less the return. There are many great examples of ‘native’ 1440p resolutions that could convincingly pass for a 4K image – or at least, still looked great on a 4K screen. We worked with some fantastically talented people and produced some interesting examples of a ‘clarity index’ that worked by comparing TAAU-upscaling to native resolution rendering between 1080p and 2160p, and effectively removed the pixel count altogether in favour of quality comparison based on what the human eye actually sees.
