Highlight: if the illuminated surface is shiny, it will reflect a bright highlight. This is not the same as the center light. The location of the highlight depends on the angle of the light and the location of the viewer’s eye. The closer you move your viewing angle toward the direction from which the light originates, the closer the highlight will be to the middle of the center light. The more you move your viewing angle toward the shadow side, the closer the highlight will be to the core shadow.