Particular Halo

Particular Halo
Here’s the situation:

I am creating an effect for a glowing halo to circle an actor’s head (shot against greenscreen). She moves about a bit.

The concept is a particle effect (Trapcode Particular) with the particle at birth being at it’s largest size, then a rapid falloff to pencil thin. The particles should form a circular trail in the form of a halo. It should look like an electron circling an atom and leaving a glowing tail. The particles will have a slight glow applied. I’ll kill the particles off after one rotation of the emitter. It's ok if the head moves and the particles move away from the head (slight inherit motion)

I will manually track the halo to the head (the shot is only 2 seconds long). I am thinking that I can use the keyed plate as a 3D layer and have the 3d particles on the backside of her head masked out.

The math and mechanics is what is dogging me. I’d like a mathematical solution, since I will be using the effect on other shots, as well.

My idea is to link the Particular effect to a null, rotate the null, and translate the null about to move the entire setup about.

However, when I pickwhip the location and rotation to the null, it attaches to the nulls rotation point. So when I rotate the null, Particular rotates in place. I then tried a lame x+100, which did move it out, but it still rotates in place.

Any hints?

Thanks in advance!

Mark E. Poole
Director
Anubis Digital Studios