Create Deformers > Blend Shape >
Origin
Specifies whether the blend shape will be relative to the base object shape’s position, rotation, and scale. Click Local or World. The default is Local.
Local will blend the base object shape to the target object shape(s) while ignoring differences in position, rotation, and scale between the base object and the target object(s). For facial animation setup, you would typically want to select Local. In general, Local is useful when you want to have your target object(s) in various separate positions for easy viewing but don’t want their positions to affect the deformation.
Target Shape Options
Specifies whether the blending will be in series or in parallel.
If on, the blending will be in series. Shape transitions will occur in the order in which you selected the target shape(s). The effect will be that the blend shape will be able to change from the first target object shape, to the second, and so on, back and forth through the series of target object shapes chained together as “in-between” shapes.
If off, the blending will occur in parallel. Each target object shape can influence the blending simultaneously in a parallel fashion rather than one after another in a series. Typically, for facial animation setup, you want In-Between off so that you can have a variety of basic facial expressions that form the basis of all the possible expressions. Because the blending is in parallel, you can control the influence of each basic expression at any moment to get a nearly infinite variety of highly nuanced expressions. Default is off.
Specifies whether to delete the target shape(s) after creation. Deleting target shapes can be useful if you don’t need to see or manipulate the target shape(s) and you want to improve display performance. However, be sure to save a copy of the target shapes in case you later decide you need to adjust them. Default is off.