Nvidia has released DLSS 4.5 Ray Reconstruction (RR), an update designed to combat the visual artifacts that often plague ray-traced and path-traced games. The technology aims to address the 'denoising pass' necessary to convert low-fidelity ray-traced images into a stable final frame, a process that can introduce visual weirdness, particularly in motion.
Path tracing, which aims to simulate light accurately in games, is computationally expensive. Even with current methods that use a limited number of rays to approximate the scene, the hardware demands are significant. This performance hit means many titles rely on denoisers to fill in the gaps between sampled rays. These denoisers typically track pixels across multiple frames to gather more data for interpolation, but this process can break down when objects or characters are in motion, leading to artifacts and smeared details.
DLSS 4.5 Ray Reconstruction replaces these hand-tuned denoisers with an AI-based system that works in conjunction with Nvidia's upscaling models. The new version integrates the second-generation Transformer model, previously introduced in DLSS 4.5 Super Resolution, into the Ray Reconstruction feature. Nvidia states this update brings several key improvements:
An efficient denoiser with 35% more compute capability and 20% more parameters, maintaining similar performance to the previous model. Enhanced Super Resolution that leverages deeper spatial awareness and more intelligently uses game engine pixel sampling and motion data for improved lighting accuracy and temporal stability. A larger training dataset for the AI model, enabling it to reconstruct scenes more accurately. Finer developer control over temporal accumulation for precise tuning of model response. The update is available via the Nvidia App. Users can enable it by selecting a supported title, navigating to 'DLSS Override - Model Presets,' and choosing 'Preset F' from the 'Ray Reconstruction' dropdown.
Supported games include Alan Wake 2, Cyberpunk 2077, Resident Evil Requiem, and Alan Wake 2, among others. Nvidia claims that while complete path-traced fidelity is not yet fully achieved, DLSS 4.5 RR delivers a more stable image with less 'boiling' textures and trails, while also restoring lost detail. Comparisons in games like Resident Evil Requiem and Cyberpunk 2077 show a marked reduction in shimmering textures and artifacts on surfaces and backgrounds, with textures resolving more quickly and clearly.
In Alan Wake 2, the update reduces dreamlike trails around characters, though some minor artifacting can still be present. The new model also appears to enhance the level of detail visible on environmental textures. Despite these improvements, the article notes that a combination of advanced AI modeling and more powerful hardware will likely be necessary to fully perfect path-traced visuals.
DLSS 4.5 Ray Reconstruction is compatible with all generations of GeForce RTX GPUs and does not significantly increase system resource demands compared to its predecessor. However, Transformer-based DLSS features can place a heavier load on older RTX hardware, such as Turing and Ampere generations, which could benefit more from performance enhancements than higher-end cards designed for demanding ray-tracing workloads.