Indeed, Mr. Dyhrenfurth had failed several times. He was the cameraman for a 1952 Swiss expedition that saw Raymond Lambert, accompanied by Mr. Norgay, get within 800 feet of Everestâs summit. In 1955, he tried and failed to climb Lhotse, the worldâs fourth-highest mountain, also in the Himalayas. And in 1958, he roamed that range in an unsuccessful search for signs of the mythical animal known as the yeti. (He was convinced it existed and was a species of large ape.)
Mr. Dyhrenfurthâs breakthrough began in May 1960, when he was the cameraman for a Swiss-Austrian expedition to Dhaulagiri, a Himalayan massif that includes the worldâs seventh-highest mountain.
The next month, he sought permission from Nepalâs government for an American expedition to climb Mount Everest. He received a permit in May 1961.
He recruited a team that, by the start of the climb in February 1963, had grown to 19 members, including climbers, scientists and photographers. They were supported by some 900 porters carrying about 26 tons of food, clothing, equipment and scientific instruments.
But a big disagreement arose, as a National Geographic article in 2012 recounted.
Two of the climbers â Thomas F. Hornbein, an anesthesiologist, and Willi Unsoeld, a Peace Corps director â argued that climbing in Mr. Hillaryâs footsteps was too modest a goal, and urged trying a new but more dangerous route, the West Ridge.
Mr. Dyhrenfurth said that getting an American to the top was the priority, and that Mr. Hillaryâs route, the South Col, was the more certain â if less adventurous â path. Mr. Whittaker sided with Mr. Dyhrenfurth.