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Some production integrators support a solution to this with a parameter called "Stochastic Opacity Depth". This value defaults to 0, meaning "off". However, at each increment, it tells the renderer to composite a semi-opaque color instead of sample randomly at that specified depth and no further. Below are example examples at depth 1, 2, and 3

Depth 1, notice the areas of the plane where there is no stacking are now free of noise.

Depth 2, notice that planes overlapping one another once are now free from noise.

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