The Fog 3D effect simulates fog by behaving as though a scattering medium is in the air that makes objects look more diffuse as they get more distant along the z axis.

This effect works with 8-bpc, 16-bpc, and 32-bpc color.

Note: As with all effects in the 3D Channel effects category, the Fog 3D effect depends on depth information from image sequence files of the kind rendered out of a 3D application. For general information on 3D Channel effects, see About 3D Channel effects. For information about simulating fog in After Effects, see Fog, smoke, clouds.


Fog Start Depth 
Where along the z axis the diffuse scattering begins.

To determine the depth of an object, click it in the Composition panel or Layer panel using the Selection tool while the effect is selected.

Fog End Depth 
Where along the z axis the diffusion reaches its maximum.
Scattering Density 
Determines how quickly the scattering occurs. The higher the value, the more dense the fog appears from its starting point.
Foggy Background 
Creates a foggy background (default). Deselect to create transparency at the back of the 3D scene for compositing on top of another layer.
Gradient Layer (Optional) 
A grayscale layer to use as a control layer, the luminance values of which apply to fog density. For example, use the Turbulent Noise effect to create a swirling control layer for atmospheric fog. Make sure that the dimensions of the gradient layer are at least as great as the dimensions of the 3D scene layer.
Layer Contribution 
How much the gradient layer affects the fog density.