.When you split an image into its RGB, HSL, or CMYK channels, Paint Shop Pro creates a greyscale image for each channel. Use one of these channel images to create a mask for the original image or another image.
To create a mask from a channel:
Split the image into channels using one of the Image > Split Channel commands, and leave the resulting greyscale images open in the workspace. For more information, see Working with Color Channels.
Select the image where you want to create the mask layer.
Choose Layers > New Mask Layer > From Image to open the Add Mask From Image dialog.
In the Source window drop-down list, select which channel to use for the mask.
In the Create mask from group box, select the Source opacity option.
To reverse the transparency of the mask data, mark the Invert mask data check box.
Click OK.
The mask layer and the selected layer are added to a new layer group. The mask layer applies to the selected layer only. To apply it to all underlying layers, drag it from the layer group to the main level.
For information on editing the mask, see Editing Masks.
To view the mask on the image, on the Layer palette click the Mask Overlay toggle .
Creating Masks from Selections