Fractal noise effect – Adobe After Effects User Manual
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Radius
Threshold
Note:
Fractal Type
Noise Type
Invert
Contrast
Overflow
Clip
Soft Clamp
Wrap Back
How far the effect searches for differences among pixels. High values make the image blurry. Use the smallest value that eliminates the
defects.
How different pixels can be from their neighbors without being changed by the effect. Use the highest value that eliminates the
defects.
Fractal Noise effect
The Fractal Noise effect uses Perlin noise to create grayscale noise that you can use for organic-looking backgrounds, displacement maps, and
textures, or to simulate things like clouds, fire, lava, steam, flowing water, or vapor.
This effect works with 8-bpc, 16-bpc, and 32-bpc color.
The Evolution controls create subtle changes in the shape of the fractal noise. Animating these controls results in smooth changes of the noise
over time, creating results that resemble, for example, passing clouds or flowing water.
Chris Zwar provides an article on the
that explains how the Fractal Noise effect works, including many details and images
regarding the inner workings of the effect.
Stu Maschwitz provides an example project on his
uses the Fractal Noise effect to create the corona of the Sun.
Harry Frank provides an animation preset on the
uses Fractal Noise to create a star field.
Maltaannon (Jerzy Drozda, Jr.) provides a video tutorial on the
that shows how to use the Fractal Noise effect to create a
star field and then use a star field as a skybox to provide a distant backdrop in a 3D world.
The Turbulent Noise effect is essentially a modern, higher-performance implementation of the Fractal Noise effect. The Turbulent Noise effect
takes less time to render, and it’s easier to use for creating smooth animations. The Turbulent Noise effect also more accurately models turbulent
systems, with smaller noise features moving more quickly than larger noise features. The primary reason to use the Fractal Noise effect instead of
the Turbulent Noise effect is for the creation of looping animations, since the Turbulent Noise effect doesn’t have Cycle controls.
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
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.
The type of interpolation to use between the random values in the noise grid.
Inverts the noise. Black areas become white, and white areas become black.
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.
Remaps color values that fall outside the range of 0–1.0, using one of the following options:
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.
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.
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.
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