Creating Atmos Light Rays Projection, from Behind the Camera

[kirk]

You can find some smart people (and me) discussing this very topic here:

Cinema Projector Beam

It’s been a couple years now, but I have done this exact thing. It was pretty fiddly and slow to render, but it worked. The trick was that the light/rays combo breaks if they get too far outside the frame of your Action. I seem to remember having to build a super-sized action node with the light in frame, with my rays and source image/gobo attached, and then comp/scale/repo it downstream. I also remember having to crank my light and sample values extremely high to get the ray definition I wante…