3-Point Lighting

3-point lighting is a technique that was originally developed for lighting up subjects and scenes for film. As technology has progressed over time, 3d software has empowered the user with the ability to simulate life and elements in it such as light. 3d Software calculates how light falls onto objects, the colours it forms and the shadows that are caste by it. One also has a control of the aspects of the lighting that is not as easy to set up in real life. How lighting hits a scene or an object can affect ones mood. This is because of how one associates with the different colours, brightness, contrast and tones of light. The following explains how one can set up a 3-point lighting rig.

Types of Lights
Each light of the 3-point lighting technique has it’s own distinct purpose. The Key light is normally the strongest and is placed on the side of a subject, which casts shadows on its opposite side. The Fill light has less strength than the Key light, approximately half, and is placed on the opposite side of the main light. It is used to allow the subject to be more visible and softens the illumination of the subject from the key light. The Back light is placed behind the subject. It normally has less strength than the fill light. It is used to allow the subject to appear more separate from its background and have more form.

3 Point Lighting Technique
Before working with the lighting of a scene one must ensure that there aren't any lights already on it by deleting them. Each new scene usually has a default light, which should be deleted from the explorer. To move the lights one can select the light 'root' which dictates the position of the light. To control the direction of the light one can either use the rotate tool or move its 'effecter'. To create the first light one can create it from selecting the ‘primitives tab’, ‘light’ and selecting a type of light depending on kind and strength one requires using. This is the key light that should be placed higher than the other lights. To create the second, which is the Fill light, one can create it the same way but it should placed lower than the Key light. Lastly the Back light should be placed the lowest of all the lights. There should be a certain lighting rig for each different scene and subject because using the same lighting would not suite scenes such as indoor and outdoor scenes.

An Indoor Scene
http://www.cgarena.com/freestuff/tutorials/homefire/index3.html

This is an example of a scene that doesn't use the 3-point lighting system. Instead it uses lighting called global illumination that lights the whole scene evenly. The lights are placed by the models, which represent light sources. When rendering, Pass of Ambient Occlusion was also used.


References:
http://www.mediacollege.com/lighting/three-point/
http://www.cgarena.com/freestuff/tutorials/homefire/index3.html