In a post on Writers in the Storm, Lisa Hall-Wilson offers advice for writing in deep third-person point of view. “Deep POV is one character at a time living out a story with the reader at their side, in their head,” she explains. “When writing entirely in deep POV, every word on the page comes to the reader filtered through the point-of-view character. The reader receives all info through the point-of-view character, not the writer (as they would in limited third person).”
That closeness of POV means that all your details – descriptions of character, setting, emotion, and dialogue – are filtered through your narrator and described in your narrator’s voice and with their opinions, without the author’s filter.
Hall-Wilson gives some before-and-after examples of how a writer might unintentionally insert themselves into deep POV writing and how they can extricate themselves.