This tutorial describes the basic concepts of image masking and shows some examples of how to use masking to change your image in subtle and very distinctive ways. Masking is a powerful tool, and Sagelight has many extensive masking functions, ranging from easy masking tools to more advanced masking effects, including mask feather controls, draw mask, and separate channel selection. This video just discusses the basic masking concepts, so you don’t need to know anything about Sagelight (or even use Sagelight) to learn how masking works in general.