Professional dog walker Jon Lovette of Jonny Walkers walks with dogs at Crissy Field on October 19, 2011 in San Francisco, California.

David Hall’s photographs of scenery and creatures off the coast of Canada in the Pacific Northwest portray serenity under the water, which belie the extreme challenges he faces to get his images. For each shoot, Hall wears a dry suit, a neoprene body suit that covers all of his body but his head and traps air inside to keep him warm. Water temperature in Canada’s British Columbia typically ranges between 45 and 50 degrees Fahrenheit. Photo: Moon jellyfish and cross jellies. (Photo by David Hall)

Photographer Andy Hall joins the thousands of fans from west Africa who have gathered for Baaba Maal's annual Blues du Fleuve festival in Senegal. Here: Dancers wait to perform on stage. (Photo by Andy Hall/The Observer)

The Royal Air Force Red Arrows perform the “Gypo Split” during their first public aerobatic display since the tragic death of Flt Lt Jon Egging on September 2, 2011 in Chatsworth, England. (Photo by Christopher Furlong/Getty Images)

Actress Scarlett Johansson Honored With The Star On The Hollywood Walk Of Fame on May 2, 2012 in Hollywood, California. (Photo by Jon Kopaloff/FilmMagic)

A model presents a creation at the Sophia Webster presentation during London Fashion Week in London, Britain February 20, 2017. (Photo by Neil Hall/Reuters)

Cheerleaders wait to perform before the New Year's Day parade in London, Britain January 1, 2017. (Photo by Neil Hall/Reuters)

Wrestlers perform at an all female wrestling event in London. England on August 17, 2017. (Photo by Neil Hall/Reuters)