This is my first attempt to do volumetric lighting. I've added some light fog to the street scene, and I want shafts of sunlight to be coming down. I built a box [four deep sides and a bottom with holes] and installed spotlights shining down in it. But I can't see light shafts. The box is just above the camera frame. Can't bring it down any further. Is there not enough fog? Or, is this not the way to go? Gels, perhaps? I've yet to use gels either. What might the proper gel look like?