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To enable custom alphas for certain objects, enable the Custom Alpha channel checkbox in the Channels panel and open the Custom Alpha Channels Editor.
Enabling the export of Custom Alpha channels in Studio
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In this editor, you can define the different alpha channels you want to have (left column), set a name to identify each channel, and assigning the object or group of objects to be included in the channel. This assignment is not exclusive, so any object can be in more than one alpha channel.
Creating different alpha groups for the car body, the wheels and the whole car object
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The masks will be exported as independent alpha images in the indicated format.
The Custom Alpha channel feature allows you to get independent masks for the selected group of objects. Here the car body, the wheels and the whole car
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- Click the "Set alphas" button to open the Custom Alpha channels editor
- Create a new custom alpha channel and name it
- Click the + icon next to the Materials column and select one or more materials that should be used to create the selected custom alpha channel.
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The main render, the alpha created from the red material and the alpha from the yellow material.
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