Photoshop Depth Masking Selects by Space, Not Edge

Photoshop's depth masking skips edge detection entirely and reads spatial depth instead, so a subject three metres from a background gets isolated cleanly even when colours and tones blend together. If you're cutting out subjects against complex environments, like a person in front of a cluttered office or a product shot with overlapping props, this tool does the work that used to take three rounds of Pen Tool cleanup.