When you enable time remapping, a keyframe is placed at beginning of movie - you drag I used the entire capture of the clouds floating by but used the 'time remapping' feature to reduce the length of time and thus the length of the file. It was pretty large without compression - I used another cool After Effects trick I like, time remapping, and that is - to actually capture enough of the clouds floating by to actually see them float by - ( that sounded bit funny but ) it required about 45 seconds - which is pretty long for an animation. When I saved my movie in After Effects, I checked the format options 'dithering' and 'looping', mine didn't work otherwise and it's one of those really nice effects with very little work.You now have the animated movie as the background property and with this, you have motion graphics as your background adding much more life to your site, but placed typically at the header section so it doesn't compete with your content. Animated gifs are too easy - just like setting a background image for a div, you specify your animated gif, and that's pretty much it. That's where animated gifs come in. It's easy to use an image for a background on your site, maybe just a section but it's not so easy to use a movie. Motion is the effect and some of the best motion is the natural effects we capture in our everyday life.
