Can art change the world? Photographer Robert Glenn Ketchum thinks so. He’s used his career as a highly-respected color landscape photographer to build political support for cleaning up and protecting places of natural beauty and ecological importance. Ketchum’s current exhibit pairs his work with the work of another photographer who inspired him. It’s called “Regarding the Land: Robert Glenn Ketchum and the Legacy of Eliot Porter,” and it runs until January 7th at the Amon Carter Museum in Fort Worth. We’ll spend this hour with Robert Glenn Ketchum.