Consider the following when producing separations for documents with gradients:
A gradient created in InDesign that contains a combination of spot and process colors will be separated onto both the process and spot plates.
A gradient that contains process colors will be separated onto the process plates.
A gradient that contains two tints of the same spot color will be separated onto a single spot color plate.
To create a gradient that separates on one piece of film between a spot color and white, create a gradient fill between the spot color and the Paper swatch in the Swatches panel.
If you create a gradient between two spot colors, you should assign different screen angles to those spot colors. If two spot colors have the same screen angle, they will overprint each other. If you’re not sure what the angles should be, consult with your prepress service provider.