Selections, masks and channels with Celia Henderson

How do these three core elements of Photoshop work together?  Why do you need to know a bit more about them.  We’ll spend some detailed time in the Select and mask workspace, look at how to create selections from the channels in your image, save and re-use selections.  Modify existing selections. Use Filters specifically designed to adjust masks. Work on masks to remove halos. And how about creating your own customised depth of field by creating an alpha channel and understanding a depth map.