To animated or not to animated?

Web Banner Tip #8 - To animated or not to animated?
Animated banners generate almost 30% higher click-thru rates than static banners. The main drawback is that animation results in larger file sizes. However, optimizing an animated GIF banner by decreasing both the number of colors used and vertical color change, one can bring the file size below the required value.
An important point regarding animated GIF banners is the use of photo-realistic images. GIF images can contain only 256 colors and the image compression algorithm (LZW: Lempel-Zev-Welch) works best when the image has large areas of single color. Since photos are complex images, the LZW compression algorithm is not able to do full justice, resulting in large file sizes. Hence, it is advisable to either avoid the use of photos in animated GIFs or keep the animation to a minimum if photos are employed.
Using Flash, we can embed photos as JPGs, which is the correct format to use for photographs and other complex images. Furthermore, we can correctly control the compression levels of JPG. With Flash, the text or even the photo can be animated.

Take a look at the Flash banner I created for a client - Click here. This banner contains 4 photos that have been animated and a large image of the American flag used as the background - a total of 5 photo-realistic images. The physical dimensions of this banner are also quite large, 160×600 pixels, but the file size is 18kb!