The editors of Smithsonian magazine have just announced the finalists in their 12th annual photo contest, selected from more than 26,500 entries. They've kindly allowed me to share several of these images here from the competition's six categories: The Natural World, Travel, People, Americana, Altered Images and Mobile. Captions were written by the photographers. Be sure to visit the contest page at Smithsonian.com to see all the finalists.