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Adaptive Metric: Make use of the improved Variance sampling algorithm as the default. You can use the Contrast metric as the older technique to match previous renders. The new technique improves the consistency of noise frame to frame.

• • Contrast: An older metric based on the contrast threshold between samples, this will match sampling from recent previous versions
  • Variance: An improved perceptual variance scheme that should provide consistent noise frame to frame
  • Half Buffer: The older "Advanced" sampling technique, note that this may sample more aggressively and you should increase your Variance setting to avoid over sampling

Adapt All: Apply the sampling quality criteria (pixel variance) to all color/illumination AOVs. This can increase render time as some AOVs may have more noise than the Beauty and trigger more samples through all the AOVs.

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