User Guide

Chapter 2: Documents and Setup
Web: Uses a standard color palette supported by major Web
browsers. The range of colors in the Web palette, however, can
cause color shifts in images with many shades of a few colors.
Uniform: Uses a palette of colors that are uniformly distributed
through the range of possible RGB colors.
Exact: Creates a palette from the actual colors in the image, if the
image contains fewer than 256 colors. If the image contains more
than 256 colors, Canvas uses the Adaptive option.
To apply a custom or system color palette to a paint object
before saving in GIF format, select the paint object and choose
Image | Mode | Indexed. In the dialog box, select a palette
option and click OK. To modify an Indexed mode paint object,
choose Image | Mode | Color Table
Optimized Select this option to merge single pixels into similar colored areas to
produce smaller file sizes. However, in images with fine lines or detail,
this option can reduce image quality. This option is less effective when
Dither is also selected and an image has a limited number of colors.
Dither Select this option if you want Canvas to use dithering to simulate a
greater range of colors. Dithering can make an image appear to have
more colors than are in a limited color palette, but it can also make an
image appear grainy or noisy. To control the amount of dithering, enter a
percentage from 1 to 100 in the text box.
Interlaced Select this check box to save the image as an interlaced GIF. Interlacing
divides the image data for faster initial display in Web browsers that
support interlaced GIF images; i.e., the image appears progressively on
the Web page.
Selecting transparent colors
The Dropper tools in the Export Preview dialog box let you make colors in a GIF image transparent.
Click in the color palette or the current preview image to select colors for transparency. When you
select a color, it becomes highlighted in the grid.
Use the regular dropper to select one transparent color. If you click another color, it replaces the
current transparent color.
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