With the Multi matte Render Channel, only three colors are possible: red, green, and blue. In comparison, other matte render channels can include many colors to represent each material or object in a scene with a different color. With Multi Мatte, a single R, G, or B channel can be used directly as a matte, eliminating the step of selecting the color in the compositing software. This ease of use makes Multi Мatte a popular choice for compositors.

The Multi Мatte Render Channel includes anti-aliasing.

To represent all the objects or materials in a scene with just the available red, green, and blue colors, several Multi Мatte Render Channels can be generated for a single rendering, each with different Material ID or Object ID settings.

UI Path: ||V-Ray Node Editor|| > World > Render Channels > Matte > V-Ray Multi Matte

Red/Green/Blue Objects – Use these sockets to connect objects to either the channel Red, Green, or Blue channel. Choose whether the objects to be included or excluded from the lists.

See the Render Channels page to find out where you can find these properties.

Channel Name – Customizable name for the render channel.

Mask Type – Specifies how the mask is generated:

Separate Channels – Considers all three Red, Green, and Blue Ids.
White – Creates a mask only for the objects with the specified Id.

Id – When Mask Type is set to White, you can specify the id of the object to be masked.

Red/Green/Blue Id – When Mask Type is set to Separate Channels, these parameters set the ID used for the respective channel.

Id Source – Specifies how the Red/Green/Blue Ids are read.

Object ID – Multimatte considers the Red object ID, Green object ID, and Blue object ID values to be the Object ID and renders the R, G, and B channels accordingly.
Multimatte ID – The Red, Green, and Blue Ids are considered as the Material ID.

Enable Deep Output – Includes this render element in deep images.

Affect Matte Objects – Determines whether to include matte objects when generating the render element.

Consider For Anti-Aliasing – When enabled, anti-aliasing is used where possible.

Mode – Selects whether to include or exclude the specified objects in the list.

Red/Green/Blue Channel Objects – Creates a list of objects/collections to be excluded or included in the respective channel. When set to Include, considers the Object List as an inclusive set. All objects/collections not mentioned in the list are not rendered with this render element. The opposite is true when the lists are set to Exclude Mode. Use the Remove button to remove any selected items from the respective list.