Carol McNulty, 28th Medical Operations Squadron optometry technician, performs an auto refraction test on Senior Airman Spencer Butler, 28th Operations Support Squadron air traffic controller at Ellsworth Air Force Base, S.D., Sept. 12, 2013. The optometry clinic administers eye exams, issues corrective lenses, and acts as a liaison for optical surgeries and services to Ellsworth Airmen and their families. (U.S. Air Force photo by Airman 1st Class Alystria Maurer/Released)