Adobe After Effects CS4 User Manual
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USING AFTER EFFECTS CS4
Effects and animation presets
Last updated 12/21/2009
The distribution of the added noise over the color channels does affect the overall color of the resulting image. With a
dark background, the noise tends to add to the image visually, so a red tint or more noise in the red channel gives a
reddish hue to the image. With a bright background, the noise tends to subtract from the image visually, so a red tint
or more noise in the red channel gives a cyan color. The result also depends on the Blending Mode control in the
Application controls group.
Note: The actual grain of your image may vary from the film presets, because of factors such as exposure and scanning
resolution.
You can use the controls for the Add Grain effect to do the following:
•
To reproduce the grain of a particular film or photographic stock, choose the film type from the Preset menu for
the Add Grain effect in the Effect Controls panel.
•
To adjust the intensity and size of the applied grain and introduce a blur, adjust the Tweaking controls group for
the Add Grain effect in the Effect Controls panel.
•
To modify the color of the added noise, adjust the Color controls.
•
To define how the color value of the generated noise combines with the color value of the underlying destination
layer at each pixel, choose a Blending Mode in the Application controls group.
•
To define how much grain is added to each tonal area in your image and the midpoint, adjust the Shadows,
Midtones, Highlights, and Midpoint values in the Application controls group.
•
To animate the added grain, adjust the properties in the Animation controls group.
•
To apply the effect to the entire image, choose Final Output from the Viewing Mode menu.
Tweaking controls for Grain effects
The Match Grain and Add Grain effects share a group of Tweaking controls. You can use these controls to modify the
intensity and size of the noise and to introduce a blur, all of which can be done across the three channels or individually
for each channel. You can also change the aspect ratio of the applied grain.
Note: The values of the Tweaking controls are relative to the noise sampled in the source layer: a value of 1.0 leaves that
property of the source noise unchanged, while higher and lower values alter the applied noise.
Adjust any of the following controls in the Tweaking controls group:
Intensity
Controls the amount of variation in brightness and color strength between pixels in the generated noise,
which determines the visibility of the noise. Increasing the value does not change the position or size of each grain but
makes the grain appear to pop more; lower values give a more subtle muted appearance.
Channel Intensities
Controls the contrast between pixels in the generated noise separately for each channel. For
example, you may want to add more grain to the blue channel to emulate film.
Size
Adjusts the size of the generated grain in pixels.
Channel Size
Adjusts the size of the generated grain in pixels independently for each channel.
Softness
Sets the amount of softness in the grain.
Aspect Ratio
Controls the ratio of the width of the generated grain over a constant height of 1; this setting is useful
for emulating the effect of anamorphic lenses or for aesthetic effects. A value higher than 1 stretches the grain
horizontally; values smaller than 1 squash it horizontally.
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