Autodesk 62205-051408-9001 User Guide - Page 232

9 Working with Image Channels 7. Draw a series of circles in the shape of "thinking bubbles." 8. When you have completed drawing on the alpha channel, choose Window | View Mode | Alpha to see what the alpha channel looks like. 9. Choose Window | View Mode | Normal. You return to the normal view mode. 10.Click the Back button to return to the previous view or, in the Workspace panel, double-click the Composite operator. You return to the composite (and can see what our subject is thinking about). Importing Files with Alpha Channels If the footage you import contains an alpha channel, Combustion automatically uses it to determine the layer's transparency. If there is no alpha channel in a clip or still image, Combustion automatically creates a default alpha channel. The default alpha channel has no effect on a clip's transparency. You can modify the alpha channel using Paint, a Keyer, a mask, or various channel effects. For example, you can import an animated 3D logo into Combustion rendered with an alpha channel and build a composite using any clip as a background for the logo. You can also create an animated 3D logo in 3ds Max (on Windows) and render it with an alpha channel. You can then import the logo into Combustion and build a composite using any clip as a background for the logo. Interpreting Alpha Channels In some cases, certain file formats may be interpreted incorrectly. For example, if you notice fringing or other unusual edge artifacts in your image or clip, change the footage channel settings. You can modify an interpretation for each layer by selecting or changing the type of alpha channel 216