Thursday, December 24th, 2009
Autodesk Combustion has an extremely powerful tool – 3D fog for simulating and rendering realistic fog in your compositions. But 3D fog uses a Z-Depth which is usually obtained from 3D software packages like Maya or 3D Max while rendering. What if you working on 2D composite and need finish it quickly. To speed up things you can use pre-made fog footage. So whenever you want to composite fog onto footage, you can just make use of this footage.
Create a new composition – File->New and import your footage – File->Import Footage.
Create a new composition and add your pre-rendered fog footage to it.
Add a Compound blur operator to footage. Go to operator settings by double clicking on compound blur node. Set the layer input to fog with luminance channel selected. Adjust the blur value to simulate diffraction.
Add Set Matte operator to fog. Choose the layer – fog and set the input channel to luminance.
Create a new composition “output”. Link the footage and fog node to the output node as shown in schematic diagram. Make sure that fog layer is on top on footage layer.
With this you are done.