George O. Jackson de Llano a Mexican American photographer whose snapshots of long-held festivals in Mexico will open in a large show at the National Museum of Natural History. Jackson de Llano will stop by to discuss his journeys and discoveries over the decade-plus that he shot the indigenous communities. The show of his work opens Sept. 26. The talk is Sept. 29, at 2:20 pm in the Baird Auditorium, 10th and Constitution Avenue NW. 202-633-1000. And it’s free!