Adobe After Effects CS4 - Manual (Page 469)

463 USING AFTER EFFECTS CS4
Effects and animation presets
Last updated 12/21/2009
Offset Darkens or brightens the shadows and midtones with minimal change to the highlights.
Gamma Correction The amount of gamma correction to use for adding an additional power-curve adjustment to the
image. Higher values make the image lighter; lower values make the image darker. Negative values are mirrored
around zero (that is, they remain negative but still get adjusted as if they were positive). The default value is 1.0, which
corresponds to no additional adjustment.
Bypass Linear Light Conversion Select to apply the Exposure effect to the raw pixel values. This option can be useful if
you manage color manually using the Color Profile Converter effect.
More Help topics
“ Adjust exposure for previews ” on page 207
“ Color depth and high dynamic range color ” on page 274
“ Color correction and adjustment ” on page 279
Gamma/Pedestal/Gain effect
The Gamma/Pedestal/Gain effect adjusts the response curve independently for each channel. For pedestal and gain, a
value of 0.0 is completely off, and a value of 1.0 is completely on.
The Black Stretch control remaps the low pixel values of all channels. Large Black Stretch values brighten dark areas.
Gamma specifies an exponent describing the shape of the intermediate curve. The Pedestal and Gain controls specify
the lowest and highest attainable output value for a channel.
This effect works with 8-bpc color.
More Help topics
“ Color correction and adjustment ” on page 279
Hue/Saturation effect
The Hue/Saturation effect adjusts the hue, saturation, and lightness of individual color components in an image. This
effect is based on the color wheel. Adjusting the hue, or color, represents a move around the color wheel. Adjusting the
saturation, or purity of the color, represents a move across its radius. Use the Colorize control to add color to a
grayscale image converted to RGB, or to add color to an RGB image.
This effect works with 8-bpc, 16-bpc, and 32-bpc color.
Channel Control The color channel you want to adjust. Choose Master to adjust all colors at once.
Channel Range The definition of the color channel chosen from the Channel Control menu. Two color bars represent
the colors in their order on the color wheel. The upper color bar shows the color before the adjustment; the lower bar
shows how the adjustment affects all of the hues at full saturation. Use the adjustment slider to edit any range of hues.
Master Hue Specifies the overall hue of the channel chosen from the Channel Control menu. Use the dial, which
represents the color wheel, to change the overall hue. The underlined value displayed above the dial reflects the
number of degrees of rotation around the wheel from the original color of a pixel. A positive value indicates clockwise
rotation; a negative value indicates counterclockwise rotation. Values range from –180 to +180.
Master Saturation, Master Lightness Specify the overall saturation and lightness of the channel chosen from the
Channel Control menu. Values range from –100 to +100.
Colorize Adds color to a grayscale image converted to RGB, or adds color to an RGB image—for example, to make it
look like a duotone image by reducing its color values to one hue.