Add to Object Buffer
Use this page to specify up to 12 object Buffer IDs for the object. These object channels correspond to the object channels defined in the Multi-Pass setting's Channel menu.
Let's say you activate a Compositing tag in the Channel tab for a given object and assign it ID 1. If you subsequently define an object channel in the Multi-Pass settings with an ID of 1, an alpha channel will be created that matches the object. This method can be used to create any number of alpha channels.
An ID of 1 can also be assigned to other objects, letting you combine a wide variety of objects that can be output as alpha channels. Refer to the Multi-Pass chapter for more details.
Tip:Even though 12 Buffer IDs per object are available by default, additional Buffer/object IDs in excess of 12 can be defined. Simply enter the desired number (e.g., 587) in the respective Buffer field. This makes it possible to, for example, assign 20 different objects various amounts of Buffer/object IDs.