About color adjustment

Adjusting colors is similar to mixing white or black paint into colored paint; it alters the appearance of the color without altering the actual hue. In the Adjust palette, you can adjust colors in the following ways:

• Brightness makes a layer lighter or darker. Enter a value between -255 and 255. A negative value darkens the layer; a positive value lightens it.
• Contrast increases or decreases the difference between colors. Enter a value between -128 and 128. A negative value decreases the contrast on the layer; a positive value increases it. This effect is most noticeable if the layer is filled with an image, texture, or background.
• Saturation adjusts the strength of the color. Enter a value between -128 and 128. A negative value increases the amount of gray in proportion to the hue; a positive value decreases the amount of gray in proportion to the hue.
• Tint blends the current foreground color in the Color palette with the current fill for the selected layer. Enter a value between 0 and 255. A higher number increases the amount of tint added to the fill. This option is not available if the layer is filled with a color from the Color palette.
• Posterize sets the number of colors in the image. Entering 0 leaves a full range of colors in the layer. Entering 1 leaves one color in the layer, entering 30 leaves 30 colors. For example, using just a few colors for a bitmap image can change a continuous-tone image such as a photograph into areas of flat color, making the photo look like a painted poster.
• Invert changes the colors in an image to their opposites. You might use this command to make a positive black-and-white image negative or to make a positive from a scanned black-and-white negative. The normal, noninverted color is displayed in the foreground color box and background color box in the toolbox and Color palette, because it is these colors that are currently inverted.When you invert a color, the brightness value of each component of that color is converted to the inverse value on the color range slider (it shifts colors to their opposite on the color wheel). For example, the inverse of a color whose red is 255 is 0.

Note: Because negative color film contains an orange mask in its base, the Invert command cannot make positives from scanned color negatives.

To adjust colors using the Adjust palette:

1. Select the object in the Composition window and the layer in the Object Layers palette.
2. Choose Window > Adjust.
3. Choose a color adjustment.