Rendering time is directly affected by the number and type of lights. By carefully configuring the lights in your scene, you can speed up rendering considerably.

For more information about lights, see Lights [Direct Illumination].

• Use the minimum number of lights necessary in each render pass. Each light adds to the overall rendering time.

• Lights that don't cast shadows have a much lower impact on rendering time.

• Use selective lights to control the number of objects that each light affects. Exclude objects that are out of a light's range. This limits the number of calculations performed for each light and reduces rendering time.

• Avoid using area lights unless you need soft shadows.

• If you want a light to affect only a material's specular or diffuse component, open the light's property editor and check the appropriate Light Contribution options (diffuse and/or specular).

  TipYou can toggle off all of a scene's area lights before rendering by typing ToggleAreaLights in the Scripting text box.