I have a project where I have animated a steamboat moving through 3d space starting small on the horizon, then filling the frame in AE. I was wanting to take a render with an alpha into Motion, and animate particle emmiters for smoke to follow its smoke stacks. The problem is, because Motion has no 3d capability, I have to scale the emmiter over time to match the perspective of the boat's motion. When I do this, some of the relevent properties of the particles scale with the emmiter, but others don't so the smoke changes density and look. I could render out the smoke shape as a flat layer and bring it into AE to parent to the boat, but that will make the smoke look flat and parented to the boat. I was really hoping to be able to get the look of the smoke particles trailing off and dissapating into the distance. Any suggestions?