Web Design in a Nutshell, 3rd Edition

Converting to the Web Palette

Designing with web colors is one option. The other opportunity is to add (or preserve) web-safe colors in the conversion process from RGB to Indexed Color. As part of this process you will be asked to select a palette for the GIF.

To make all the colors in the image web-safe in Photoshop/ImageReady, apply the Restrictive (Web) palette when you choose Save for Web. In Fireworks, select the Web216 palette. This ensures that every pixel in your resulting GIF will be web-safe.

A better alternative is to make sure the colors in flat areas are web-safe to prevent dithering, but to allow colors in photographic or blended areas to dither as necessary to preserve image quality.

To do this in Photoshop/ImageReady, choose the Selective palette, which creates a custom palette while preserving web colors and broad areas of color. You can also use the Web Snap slider tool to control how many colors shift to their nearest web-safe neighbor. You can view the results of your choices immediately in the Optimized view when you choose Save for Web.

In Fireworks, the Web Adaptive palette creates a custom palette for the image but snaps colors to web-safe if they are close to a web palette color.