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Adaptive Metric: Make use of the improved Variance sampling algorithm as the default. You can use the Contrast-V22 metric as the older technique to match previous renders. The new technique improves the consistency of noise frame to frame.

• • Contrast-V22: 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 frameHalf 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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