Controls – Adobe After Effects CS4 User Manual
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USING AFTER EFFECTS CS4
Effects and animation presets
Last updated 12/21/2009
Note: Because the controls for the two effects are nearly identical, you can use most instructions and tutorials created for
the Fractal Noise effect to instead guide your use of the Turbulent Noise effect. (See “
Controls
Fractal Type
The fractal noise is created by generating a grid of random numbers for each noise layer. The Complexity
setting specifies the number of noise layers. The Fractal Type setting determines the characteristics of this grid.
Noise Type
The type of interpolation to use between the random values in the noise grid.
Invert
Inverts the noise. Black areas become white, and white areas become black.
Contrast
The default value is 100. Higher values create larger, more sharply defined areas of black and white in the
noise, generally revealing less subtle detail. Lower values result in more areas of gray, softening or muting the noise.
Overflow
Remaps color values that fall outside the range of 0–1.0, using one of the following options:
•
Clip
Remaps values so that any value above 1.0 is displayed as pure white, and any value below 0 is displayed as
pure black. The Contrast value influences how much of the image falls outside this range. Higher values result in a
mostly black and/or white image with less gray area. Therefore, higher contrast settings display less subtle detail. When
used as a luma matte, the layer has sharper, better-defined areas of transparency.
•
Soft Clamp
Remaps values on an infinite curve so that all values stay in the range. This option reduces contrast and
makes noise appear gray with few areas of pure black or pure white. When used as a luma matte, the layer contains
subtle areas of transparency.
•
Wrap Back
Remaps triangularly, so that values above 1.0 or below 0 fall back into the range. This option reveals
subtle detail when Contrast is set above 100. When used as a luma matte, the layer reveals more detailed textured areas
of transparency.
•
Allow HDR Results
No remapping is performed. Values outside the range of 0-1.0 are preserved.
Transform
Settings to rotate, scale, and position the noise layers. The layers appear as if they are at different depths if
you select Perspective Offset.
Complexity
The number of noise layers that are combined (according to the Sub Settings) to create the fractal noise.
Increasing this number increases the apparent depth and amount of detail in the noise.
Note: Increasing Complexity results in longer rendering times. If appropriate, try reducing the Size rather than increasing
Complexity to achieve similar results and avoid longer rendering. A trick to increase apparent complexity without
increasing rendering time is to use a negative or very high Contrast or Brightness setting and choose Wrap Back for
Overflow.
Sub Settings
The fractal noise is generated by combining layers of noise. The Sub Settings control how this
combination occurs and how the properties of the noise layers are offset from one another. Scaling successive layers
down creates finer details.
•
Sub Influence
How much influence each successive layer has on the combined noise. At 100%, all iterations have
the same amount of influence. At 50%, each iteration has half as much influence as the previous iteration. A value of
0% makes the effect appear exactly as if Complexity is 1.
•
Sub Scaling, Rotation, and Offset
The scale percentage, angle, and position of a noise layer relative to the previous
noise layer.
•
Center Subscale
Calculates each noise layer from the same point as the previous layer. This setting can result in the
appearance of duplicated noise layers stacked on top of each other.
Evolution
Uses progressive revolutions that continue to change the image with each added revolution. This method
is unlike typical revolutions that refer to a setting on the dial control for which the result is the same for every multiple
of 360°. For Evolution, the appearance at 0° is different from the appearance at 1 revolution, which is different from