Alec and Oliver discuss how DLSS 4.5 improves ray tracing denoising in Unreal Engine 5 by disabling the in-game denoiser and relying on DLSS’s advanced capabilities, resulting in superior visual quality compared to native rendering. They also explore the challenges faced by other upscalers like PSSR, emphasizing the need for better integration and backend configurability, while expressing cautious optimism about future improvements such as a potential PSSR 2.
In the video discussion, Alec and Oliver delve into the issue of ray tracing denoising problems in Unreal Engine 5 (UE5) and how DLSS 4.5 addresses these challenges. Alec explains that by turning off the in-game denoiser and relying solely on DLSS 4.5’s advanced upscaling and denoising capabilities, the visual quality of ray-traced reflections significantly improves—sometimes even surpassing native rendering quality. This suggests that DLSS 4.5 not only fixes legacy issues but also enhances the overall experience by providing superior denoising compared to the original game implementations.
Alec further speculates that this problem might not be exclusive to DLSS but could affect other upscalers such as PSSR (Pixel Streaming Super Resolution) in games like Silent Hill 2. He highlights that developers often focus their denoising efforts primarily on TSR (Temporal Super Resolution), which is native to Unreal Engine, since it is their own technology. Meanwhile, external upscalers like DLSS, XSS, and PSSR are treated as plugins, and the engine’s denoising systems may not be optimized for compatibility with them. This lack of integration could explain why similar denoising issues arise across different upscaling technologies.
Oliver adds to the conversation by acknowledging the persistent problems with PSSR, noting that despite its issues, developers continue to integrate it into games. He points out a tension between the visible problems users experience and the challenges developers face in implementing PSSR effectively. Oliver emphasizes the importance of backend configurability and compatibility with newer technologies like DLSS 4.5. Without proper design to leverage these advancements, PSSR and other upscalers may not realize the full potential of improved denoising and image quality.
Both Alec and Oliver agree that a practical solution could be for Nvidia’s DLSS plugin to automatically disable the in-engine lumen reflection denoiser when activated. Alec suggests this would be a straightforward fix that could dramatically improve visual quality on PC without requiring complicated changes from developers. In the meantime, users can manually disable the in-game denoiser through configuration files in supported games, reaping the benefits of DLSS 4.5’s superior denoising and upscaling.
Finally, the discussion touches on the future of PSSR, with rumors of an upcoming PSSR 2 version that might address some of these longstanding issues. While details remain speculative, there is cautious optimism that improvements are on the horizon. Overall, the conversation underscores the complexities of integrating various upscaling and denoising technologies within game engines and highlights how advancements like DLSS 4.5 can offer significant quality improvements by rethinking how denoising responsibilities are handled.