U.S. Air Force Staff Sgt. Anthony Sweat, 100th Maintenance Squadron nondestructive inspection journeyman, uses a specialized optical lens Sept. 2, 2015, on RAF Mildenhall, England. Using these lens means he’s able to measure and pinpoint specific discontinuities on radiographic film for weld certifications. (U.S. Air Force photo by Gina Randall/Released)