Optimized
Select this option to merge single pixels into similar
colored areas. This can produce smaller file sizes. However, in
images with fine lines or detail, this can reduce the 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 the Interlaced checkbox 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. In other
words, 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.
Use the add/subtract dropper to select additional colors to be
transparent. Each color you click becomes transparent. To
restore a transparent color, click it again.
A checkerboard pattern appears in areas of the preview image that
are transparent.
Color palette
The area below the GIF options shows the current
color palette for the image. The palette changes when you change the
Palette or Max Color option.
Saving settings
You can save the current options in the Export Preview dialog box,
and then apply the same setup to other images.
To save the current options in the dialog box, choose Save Setting in
the pop-up menu above the current preview pane. Type a name for
the saved setting and click OK. This setting will be available in the
pop-up menu above each preview pane.