I Created a map , over this map are moving some small clouds . I want some rain coming out of this clouds an now I created a black surface, used the cc rainfall effect an want to mask only the area under the clouds with a soft edge mask to let it rain only in the areas under the clouds. BUT It seems like i can not use a mask with the CC Rainfall effect because I got a rectangel with hard edges and that is looking realy stupid. (rectangle rain) What would be your solution for my task?
Thanks for your help.. Becouse of my bad english I atached a screenshot because a Picture tells more then 1000 Words ;-)
On top of your rain layer, create a shape layer by drawing a rectangle over the rain. Use a radial fill with 100% opacity for the center, 0% halfway or further out, to taste. Make the colors of the fill white -> white. Set your rain layer's TrkMat to the the shape layer.
Here's how the radial fill parameters for the rectangle shape layer looks:
And here's the comp - make sure you keep the eyeball for the shape layer off after specifying it as the TrkMak for the rain layer - AE will turn it off automatically when you set the TrkMat (so just leave it off after that).