Diana Duncan Holmes' extraordinary monochromatic photographs line the walls at Iris BookCafe, making art of such humble subjects as plastic bags blowing in the wind or the shreds of automobile tires. Three series are here: the bags, the blowouts and works Holmes calls “bowlz,” reflecting the dips and swoops of skateboard parks.There's also a curious triptych of blurred type, titled “New York Times.” A steady move toward abstraction marks the work of recent years by this Cincinnati-based, internationally recognized artist. She and her collaborator, Timothy Riordan, will discuss the works in bags, bowlz, blowouts and more, dating from 2009 through 2011, at 2 p.m. Sunday, at Iris, no charge for admission. Get there early enough to look closely at the exhibition first, and don't miss the two in the restroom. They're stunners.