Hartman's work arises from his curiosity about the interaction between humans and landscape and how each influences the other. In his first main series, Highway 69 he made large format photographs of landscapes in a transitional state; choosing to record the landscape as it is transformed into a new place. His subjects include highway construction and large urban demolition sites. Hartman finds the concept of transition intriguing, using the subject to articulate basic human desire and our need for progress. In Hartman's work the deconstruction of large buildings signifies change in human perception; what was once seen as progress is now seen as a hindrance. His photographs tell a story about society through what Hartman calls, "monuments of our time."