For those schooled in contemporary art, stepping into Artist’s Proof (aproof.net), the new gallery in Cady’s Alley, is a joy. Peggy Sparks, the space’s down-to-earth and gorgeous owner, is a Singapore-born, globe-trotting art consultant who recently moved to the District with the mission of opening a gallery that sells exclusive, yet accessible, art. 

There are two types of people who walk into an art gallery: the “just browsing” set or the serious collector looking to find a hidden treasure. But when either steps into Artist’s Proof…