DF Weekly: PS5 Pro's PSSR AI upscaling could be a game-changer
Enabling developers to focus on quality over quantity of pixels.
A new DF Direct Weekly arrives today and it's essentially two hours of myself, Oliver Mackenzie and Alex Battaglia revisiting the Mark Cerny reveal for PlayStation 5 Pro in the light of broadcast quality footage made available to the press after the event. It's a chance to reassess the introduction of the new hardware by being able to actually see the difference, with the blurry haze of YouTube compression artefacts removed from the presentation. In the process, we've learned more about the games shown and have some initial opinions about PSSR - PlayStation Spectral Super Resolution - the new AI upscaling technology used by PS5 Pro. Think of it as Sony's take on Nvidia's game-changing DLSS.
Of course, we've made a YouTube video about it embedded on this page and by extension, the audience might be wondering how we can show you the games running well on this medium if prior YT presentations could not. Well, we've been doing this for some time now and recognise that there's a limited amount of video bandwidth available - and you can get more from that bitrate budget by slowing footage down, freezing it and zooming it for extra clarity. This is particularly useful for users on mobile devices - well over half of our views the last time we looked and only growing in importance. Still not good enough for you? Well, this Direct and the Cerny presentation are available as pristine quality video downloads via the Digital Foundry Supporter Program.
The majority of titles seen in the Sony presentation last week are using PSSR upscaling and it turns out that 'countable pixel edges' - which we use to calculate internal rendering resolutions - are very easy to find, meaning we have a pretty firm lock on the details. It was somewhat disappointing to see newcomers to the DF Supporter Program share those details this weekend ahead of the show's public release and with none of the surrounding, crucial context.
- 0:00:00 Introduction
- 0:02:47 The Last of Us Part 2
- 0:11:49 Ratchet and Clank: Rift Apart
- 0:23:44 Alan Wake 2
- 0:33:27 Horizon Forbidden West
- 0:39:09 Hogwarts Legacy
- 0:45:48 Gran Turismo 7
- 0:54:35 Dragon’s Dogma 2 and Assassin's Creed Shadows
- 0:57:43 Could PS5 Pro run Elden Ring at 60fps?
- 1:03:36 Is PS5 Pro a good deal relative to PC?
- 1:16:48 Supporter Q1: With the Pro reaching $700, what will the PS6 look like?
- 1:26:42 Supporter Q2: Could PSSR run on the base PS5?
- 1:33:04 Supporter Q3: Why hasn't Sony developed machine learning based frame gen tech for PS5 Pro?
- 1:37:11 Supporter Q4: Will the high price of PS5 Pro drive people to PC?
- 1:44:13 Supporter Q5: Will low PS5 Pro sales cause development problems?
- 1:51:46 Supporter Q6: What game reveals would have excited you about PS5 Pro?
But hey - let's give you those rendering resolutions and then allow me to explain perhaps why the developers have made those choices and why it's important to consider the overall presentation, not the internal pixel counts alone.
The Last of Us Part 2: The clip shown in the presentation operates at the same native 1440p rendering resolution as the performance mode in the standard PS5 game. However, PSSR is used instead of a more basic upscale, giving a presentation comparable with native 4K. Why didn't Naughty Dog increase resolution? Well, PSSR has a computational cost on its own, while various elements such as post-processing are likely running at native 4K resolution.
Ratchet and Clank: Rift Apart: The footage looks to show much the same visual feature set as the existing Performance RT mode. However, internally rendering resolution varies between 1440p and 1800p, with a pass of PSSR to deliver a 4K output.
Alan Wake 2: There isn't much video here, but there are clearly 30fps and 60fps modes, targeting 1260p and 864p respectively. Again, as the footage was easily countable, we're confident this is using PSSR. Screen-space reflections are evident in the 60fps mode, but they are not in 30fps, suggesting RT may be in play.
Gran Turismo 7: Adding quarter res (1080p) ray-traced reflections in gameplay has a hit on GPU performance, so internal resolution drops in the clips seen to 1188p and - again - PSSR upscaling is used for a 4K output.
In terms of the rest of the presentation, we counted Assassin's Creed Shadows at 864p, targeting 60 frames per second, while there are no signs at all of PSSR present in the upgraded Horizon Forbidden West. I'm reminded of Guerrilla rolling its own checkerboard solution for PS4 Pro, as opposed to using the hardware.
Putting aside the caveat that these games may not be final - and that the upgrades may be lower resource retrofit patches as opposed to from-the-ground-up PS5 Pro implementations, it's important to understand exactly what Mark Cerny's 'Big Three' enhancements are supposed to achieve. PS5 Pro receives extra GPU horsepower, enhanced ray tracing capabilities and machine learning capabilities. The idea is for the Big Three to work in tandem, delivering superior quality visuals from a more holistic standpoint. Internal resolution is only one element of overall image quality and PSSR is already showing some promise, delivering results that diminish the importance of the base pixel count.
I can understand why some users may find some of the numbers above alarming. It's not necessarily true of Sony's first-party efforts, but many games are running at low resolutions on the standard PlayStation 5, with FSR 2 upscaling pushed too far in attempting to hit 1440p or 4K outputs. However, already we can see that the upscaling quality of PSSR lacks many of the profound issues we've noted when FSR 2 is running at very low resolutions. It's early days, it's not perfect, but there's grounds for optimism.
Based on our testing, Alan Wake 2 runs at 864p internal resolution on PlayStation 5 Pro in the 60fps clip, while the equivalent base PS5 mode operates at 847p. Firstly, we can safely assume that in transitioning from FSR 2 upscaling to PSSR, we will see a substantial quality upgrade. However, perhaps more important is to consider what Remedy will be doing with the Pro's extra resources in increasing quality elsewhere because obviously, the extra GPU horsepower in the Big Three is going to be used for features that Remedy prefers over simply increasing resolution. This is basic commonsense.
The key question remaining is how good PSSR actually is. What this week's DF Direct Weekly shows - particularly in the Ratchet and Clank footage, where we can compare to other upscaling solutions - is that Sony has made an interesting start and the fundamentals are in place, but this is still very much an emerging technology. The crucial success is that at similar resolutions, PSSR possesses fewer of the distracting artefacts that blights FSR 2 presentations that are pushed beyond their comfort level. Problems in motion in particular are far less pronounced. However, PSSR is still a nascent technology for Sony - and I would not be surprised at all if this is a proving ground for PS6. As you'll see in the Ratchet segment in this week's Direct, PSSR has some way to go before it matches DLSS - but that's just one game, of course, and similar to other upscaling technologies, we should expect to see results of various quality on a per-implementation basis.
The paradigm has been shifting for a long time now from quantity of pixels to quality of pixels and in bringing machine learning-based upscaling to consoles for the first time, PSSR allows developers to spend more system resources on how good a game can look as opposed to how high the resolution is. Now, don't get me wrong, upscaling quality does tend to improve the higher the base resolution - but it's down to developers now to choose the best balance for their games. Should they go for a 1080p presentation richer in detail, or a higher resolution 1440p alternative? Developers will need to make that call - but ultimately, it's all about the quality of the final presentation. The flexibility of machine learning-based upscaling means that 'how good the game looks' takes precedence over 'how high the pixel count is'.
Just to be clear then: if a game runs at a 'low' resolution on PS5, and an equally 'low' resolution on PS5 Pro, they are not the same thing. Improved upscaling makes a difference, but bearing in mind the extra horsepower of the Pro, we can imagine that the developers are doing more with those pixels. The extent to which this is going to be successful is ultimately down to a more subjective assessment of the presentation for each title - and that's what we'll be looking at once software arrives for review. In the meantime, enjoy this Direct and look forward to more PS5 Pro coverage.