Practical Guide to Portrait Photography Lighting - Basic Lighting Setup

Main Light: The dominant light in lighting arrangements, often also referred to as the "key light" or "modeling light." Both terms are correct because the main light indeed determines the "tone" of the scene (high key or low key), and its position creates the modeling contours formed by highlights and shadows. Relatively speaking, a softer light source is chosen as the fill light, while harsher, more "harsh" light is often selected as the main light. Parabolic reflectors, small silver umbrellas, and lights that produce specular highlights can all be chosen as the main light.