User Guide

Optimizing in the workspace 337
You can optimize 8-bit file types by adjusting their color palettes. Fewer colors in the palette
means fewer colors in the image, resulting in a smaller file size. The drawback to reducing
colors is that it can also diminish image quality.
As you experiment with different optimization settings, you can use the 2-Up and 4-Up
buttons to test and compare a graphic’s appearance and estimated file size. For more
information on using the document preview buttons, see “Previewing and comparing
optimization settings” on page 334.
Choosing a color palette
GIFs and other 8-bit image formats contain a color palette. A color palette is a list of up to
256 colors available to the file. Only colors defined in the color palette appear in the graphic;
however, some color palettes contain colors that are not in the graphic.
The following palettes are available in Fireworks:
Adaptive is a custom palette derived from the actual colors in the document. Adaptive
palettes most often produce the highest quality image.
Web Adaptive is an adaptive palette in which colors that are close to websafe colors
are converted to the closest websafe color. Websafe colors are those that come from the
Web 216 palette.
Web 216 is a palette of the 216 colors common to both Windows and Macintosh computers.
This palette is often called a websafe or browser-safe palette because it produces fairly
consistent results in various web browsers on either platform when viewed on 8-bit monitors.
Exact contains the exact colors used in the image. Only images containing 256 or fewer
colors may use the Exact palette. If the image contains more than 256 colors, the palette
switches to Adaptive.
Windows and Macintosh each contain the 256 colors defined by the Windows or Macintosh
platform standards, respectively.
Grayscale is a palette of 256 or fewer shades of gray. Choosing this palette converts the image
to grayscale.
Black and White is a two-color palette consisting only of black and white.
Uniform is a mathematical palette based on RGB pixel values.
NOTE
All file types mentioned above (except PICT, which is only supported on the Macintosh
version of Fireworks) can be saved in their original formats in Fireworks 8 from within the
“Save As” dialog box. This behavior differs from that in previous versions of Fireworks.
For more information, see “Saving documents in other formats” on page 27.