Adding Smoke to Light
Maya 2012 Tutorial
How to Add Smoke Effect to Light in Maya
By creating fog and adding noise to the light you can create a smoke effect. You also have the option to add shadows to the smoke.
Another example of this type of lighting can be found in the topic, Volumetric Lighting.
Open a scene with multiple objects.
Add an spot light to the scene (Create > Lights > Spot Light). Position the light above the scene.
With the light selected, open the Attribute Editor and soften the lights edges by adjusting the Dropoff and Penumbra settings. Adjust the Cone Angle if necessary.
Scroll down the light options and open the Light Effects tab. Click the checker-board next to the Light Fog box.
Click the color rectangle to change the fog color.
Click the checker-board next to the Density slider. In the Create Render Node panel, right click the Cloud texture button in the 3D Textures section and choose Create Texture.
Return to the light's main Attribute Editor panel and adjust the Intensity slider. You may also need to scale the light to extend the effect.