Photoshop® CS4 Bible

24.3. Creating a Web Banner

Advertising is one of the biggest money-makers on the Internet. Sure, many people go out of their way to ignore those annoying banners that often surround the content on Web pages, but the fact remains, they do bring traffic to the advertisers' sites, and for that reason, they'll keep paying ad agencies to produce them. These days, most Web ads are created in Flash — after all, Flash supports interactivity and can add all sorts of bells and whistles that entertain the user while benefiting the advertiser. But every Flash Web ad that gets delivered to a publisher's site is accompanied by an animated backup GIF version just in case. That said, making an animated Web banner is a useful thing to know how to do, and you'll learn how in this section.

There are a couple things you should keep in mind when creating Web banners:

• File-size is critical. Web publishers (such as Yahoo!, the New York Times, iVillage.com, and about a billion others) normally restrict the size of the ads on their sites, because it would make a terrible experience for visitors if they had to wait longer than expected for the site to load due to bloated ads. A common file-size limit for animated GIF images is 30 kilobytes. Some common file-size killers include photography, gradients, too many frames of animation, and dramatic changes between one frame of the banner and the next.

• The simplest way to create frame-by-frame animation is to create a storyboard in Photoshop. Create a layer ...