Divergent light “22° halo” - This is perhaps the easiest divergent light halo to understand. Imagine that you are near a point source lamp. A randomly oriented column crystal at “X” deviates the lamp light through 22° (or to be pedantic, a minimum deviation angle of 22°). The red lines show the ray’s path. The crystal appears as a bright glint. Crystals anywhere on the red ring will glint to form a circular halo. BUT, its radius is smaller than the 22° of the parallel light halo we see around the sun or moon. The closer is “X” to the lamp, the smaller is the ring.



The red ring is not the only position where crystals will glint light after a 22° deviation. Crystals anywhere on the surface of the pointed airship will do so. Crystals inside the airship do not glint 22° halo light. Crystals outside form the fainter halo extremities. The eyes see individual crystals glinting and the halo airship takes on a 3D character. The halo definitely appears to be closer than the lamp.



The superparhelion halo surface is more complicated!