I am new to Motion 2 and I have been experimenting with replicators. I have an idea. I want to take for example a car from a scene and then make it fly away by turning into doves. In Motion can I take a matte or mask to fill around the car then fill the mask with the replicator to create a dove like object then have it fly way. After that I will need to fill in the background where the car was. Is this something Motion can accomplish? I simply would like to experiment with the idea and I wondered if Motion does that stuff?
I don't think you fill in the missing car with Motion directly. You would want to have that photographed as a clean plate so when the car disappears, the hole it leaves in the top layer is filled with the video from a lower layer. You coul,d of course, create some kind of clone of the missing car pixels but that would not be an efficient way of previsualizing the effect.
You might want to shoot the car as a model on a bluescreen stage or create an automobile model in a 3D app. both might be easier than trying to replace the pixels.
The Apple Training book for Motion 2.0 has a great piece on creating a flock of birds.