i´m trying to make a particlestream coming of the mouth of someone and goes directly to someone else. The problem is that the first person is moving but the stream has to stick on her mouth. How can i track the beginning of the particles so that not the whole stream is moving.
Below is an example of what i mean.
This really depends on the shot. if it is a profile shot, simply track a point on the face near the mouth and you should be pretty good. Picwip the Particular xy to that null position. I would also use a motion path for the particles. If you need to have it attract to a certain spot on the person, you may be able to use the spherical field with a negative number to draw the particles to that point. If you have a shot where you are rotating at all, it will be a 3d track and be much harder. You may need to match move and that is a bit trickier.