Digital Lighting and Shading for 3D objects

The art of lighting design  was practised for centuries prior to the advent of computer graphics in various forms of art, such as photography, theatre, paintings and so on.  Be it a shot from a movie, a photograph or even a painting, an aesthetically well lit picture looks much more appealing than a normal picture that has been captured without giving importance to the light source.
 
Digital lighting refers to that aspect of 3D computer graphics where a 3D object or model created using a 3D software is made to look realistic by simulating the behaviour of light in real life by using lighting tools which are part of the 3D software. Lighting adds realism and depth to an existing object.  For instance, a table with a bowl of fruits in it looks much better when the background and the table are lit dimly and when the focus is made to shift onto the shape of the fruits and the bowl by lighting its edges brightly and interestingly from all three directions; the main source from either one side, bounce light from the opposite bottom of the main source and  a  backlight from the back of the object to bring out its form, thereby making it stand out and look beautiful. This process is called 3-point lighting in computer graphics.  It is one of the basic methods of lighting 3D objects. Lighting has various other attributes that have to be carefully studied, such as its reflectivity, shadows, refraction, and so on if it has to be replicated manually using the tools of a 3D software.
 
  Digital lighting  goes hand in hand with shading which is the art of giving texture to a 3D object with reference to its surface structure; the transparency, translucency, reflectivity, shininess, glossiness, bumpiness, and other surface attributes. Shaders can be designed, assigned and adjusted to develop unique looks for the objects in a 3D scene. Different 3D software enable us to create various simple and complex shaders based on our requirement. Shaders are definitions of how 3D objects respond to light ,describing their surface appearance or how they will be rendered.
 
 Therefore, shading  is complimentary to lighting and vice-versa.  Shading helps define the nature and character of a particular object and teamed with good lighting, renders almost an exact replica of the object in real life. However, it is always dependent on the skill, experience and expertise of the shading and lighting artist to make 3D objects look as realistic as possible. A good  shading and lighting artist has to possess an in depth knowledge of the scientific facts that define the behaviour of light, the factors that influence its character such as the transparency of the object it hits, the size of the light source that define the size of the shadows, and so on. It also requires an eye for detail, besides the technical know-how, software skills, creativity and an excellent aesthetic sense