Have you ever wondered what it’s like to own your own gallery? Maybe you’re mystified about what drives the constantly fluctuating value of artwork. On Tuesday’s “Leonard Lopate at Large” two giants of the New York City art scene will give you a peek into one of the city’s chief cultural exports. Cristin Tierney is the owner of Cristin Tierney Gallery in Chelsea. Cristin explained the difference between her role as a gallerist and what an art dealer does to the author Jackie Battenfield for her book “The Artist's Guide: How to Make a Living Doing What You Love,” published in 2009. “A dealer is dealing with canvases, objects, videos, or whatever the case may be. A gallerist is dealing with a career,” she said. Sotheby’s Senior Vice President Nina del Rio began her career with the company, considered one of the world’s premiere brokers of fine art, as a cataloguer in the prints department. In 1999, she began working on the launch of Sotheby’s online auction site before becoming the department head of Museum Services. Don’t miss this rare glimpse into the art world with two people who know it as well as anyone.