CG Lighting in Maya, A balance of Colors, Lights and Shadow
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Lighting plays an important role in a scene. It controls the visibility and mood of your scene. Another important aspect of lighting is that you have to save render time, more lights you have in a scene, more time you need to render them; so place lights in the scene strategically. One another thing before you work on CG lighting is that first understand the darkness. Shadows and their intensity is another important aspect which controls the mood of the scene. It is also important to understand the physical properties of the light, such as wavelength and temperature. The light we see is a combination of the different wavelengths. You must have heard of infrared and ultraviolet light. Red color has shorter wavelength while violet color has longer wavelength. If you see VIBGYOR color spectrum colors will be in following order from shorter to longer wavelengths. ROYGBIV i.e. Red, Orange, Yellow, Green, Blue, Indigo, Violet. Light in Maya doesn't perform like in the real world, but it provides controls to you to fine tune that. There are some common techniques that animators use to light the scene are called light rigs. They are kind of layouts. The first one is the famous THREE POINT rig. It has a key light as a main source, which illuminates the sides of the objects directly facing it, a fill light with low intensity to illuminate the dark edges and a back light which is placed at the angle so that it does not show up in the camera, for highlights. You should not always go by this rule, you can place additional lights to make your scene more interesting. You can also change the elevation and position of the lights. Another one is dome lighting. In this lighting technique we create a hemisphere with dim lights. That we will discuss later in coming tutorials. Some important terms related to Lighting: Direct & Indirect Illumination: Where ever the light strikes, that area is referred to be as directly illuminated whereas the areas in the shadows are dimly lit, that area is referred to as indirectly illuminated. That area is illuminated by light bouncing off different objects. This is the basic of Global Illumination or GI in CG. Radiosity: When light bounces off brightly colored objects it carries color of the object and reflects on objects, this is called color bleeding or Radiosity. Attenuation: Sets how much the strength of the field diminishes as distance to the affected object increases. The rate of change is exponential with distance; the Attenuation is the exponent. If you set Attenuation to 0, the force remains constant over distance. Negative numbers are not valid. Shadows: Shadows are vital. You should always give great attention to the shadow. Ambient Illumination: Ambient light is the considered the omnipresent light in an environment. In a 3D package you have to use ambient light carefully as it can flatten out the mood of the scene. Color Temperature or Color Warmth: Light source temperature are measured in degree kelvin. Here are some temperatures. 1000K :Color Red: Match flame, small fires. 100W house hold bulb: 2865 In next tutorial we will talk about the different light source available in Maya . For classic light tutorial visit following link... http://www.itchy-animation.co.uk/light.htm
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