V-Ray Tip: OptiX vs OIDN: Choosing the Right V-Ray Denoiser

Today’s tip: choosing the right V-Ray denoiser can save hours while protecting detail.

OptiX (NVIDIA AI) vs Intel OIDN at a glance:

• Speed
  • OptiX: Extremely fast on NVIDIA GPUs (best on RTX). Ideal for IPR and rapid lookdev.
  • OIDN: CPU-based and consistently quick on modern CPUs; scales well across cores.
• Hardware
  • OptiX: Requires an NVIDIA GPU. Uses VRAM; watch large-frame memory budgets.
  • OIDN: Runs on CPU; uses system RAM, great for very high-res frames or GPU-constrained rigs.
• Quality tendencies
  • OptiX: Excellent for low-sample previews; can look slightly “plastic” on fine textures if pushed.
  • OIDN: Often preserves micro-detail a bit better on stills; robust for final-quality denoising.

Recommended use cases:

• Look development and quick approvals: OptiX for near-instant feedback, especially with V-Ray IPR.
• Final stills: OIDN for balanced sharpness and cleanliness with moderate denoise strength.
• Animation: Both work, but reduce per-frame noise first to avoid temporal shimmer. Aim for clean inputs; keep denoise strength conservative.

Practical setup (V-Ray VFB or Render Elements):

• Add the Denoiser in the VFB (as a layer) or as a Render Element.
• Select the engine: NVIDIA AI (OptiX) or Intel OIDN.
• Enable and supply albedo and normal auxiliary passes for better edge/detail preservation.
• Start with denoise strength 0.5–0.7; increase only if necessary.
• Do not denoise utility passes such as ZDepth, Cryptomatte, or Object/Material IDs.

Sampling and thresholds that pair well with denoisers:

• Previews: Adaptive noise threshold around 0.02–0.03 with OptiX.
• Finals: Target 0.005–0.01 before denoising to minimize artifacts, especially on hair, fine bump, and glossy caustics.
• Reduce extreme highlights and fireflies at the source (balanced light intensities, sensible reflection/refraction limits) so the denoiser has an easier job.

Animation stability tips:

• Use stable GI for sequences and avoid large per-frame sampling variance.
• Keep denoise strength modest and consistent across the sequence; test 20–30 frames before committing.
• For fur, foliage, and specular sparkle, raise local sampling or roughness slightly to avoid flicker that any denoiser might amplify.

Pipeline and deliverables:

• Export multi-channel EXR with both raw and denoised Beauty plus denoised key AOVs for flexible comp.
• When using LightMix, apply your light balancing first; then finalize denoise settings for a stable result.

Quick decision guide:

• Need fastest feedback on an NVIDIA GPU? OptiX.
• Need the safest detail retention for stills or huge frames? OIDN.
• Mixed hardware or cloud nodes? OIDN ensures consistency across machines.

For licensing, upgrades, and hardware guidance tailored to your denoising workflow, reach out to NOVEDGE. Explore V-Ray options and bundles at NOVEDGE and streamline your next production with the right denoiser from day one.

You can find all the V-Ray products on the NOVEDGE web site at this page.