A documentary team becomes the first Chinese moviemaker to take cameras to the summit of the world's highest mountain.

As a child, Pasang Tharchin would stare for hours at the crowds of mountaineers who passed through his hometown as they prepared to tackle their greatest challenge: Qomolangma, known in the West as Mount Everest.

As an adult, the 36-year-old helped blaze a trail for the first Chinese documentary to record the trek from base camp to summit.

Slim, with dark red cheeks kissed by the cold, Pasang was born into a poor herding family with six brothers and sisters in Xigaze in the Tibet Autonomous Region. The city's location near the base of Qomolangma meant climbers often used it as a starting point for their summit attempts.

"The job opportunities are limited here," Pasang said in broken Mandarin. "So I went to the Tibetan Mountaineering School to train as a professional climber."

After graduating in 2003, he began working as a guide, specializing in repairing and maintaining ropes along the slope and setting up camps for climbers. He has reached the top of the world's highest mountain nine times.

Despite more than a decade of working on the mountain, he never imagined he would join a film crew and shoot the documentary Himalaya: Ladder to Paradise, which turned its lens on mountain guides. Its title is a play on the name given to the patterns on the palisades that can be seen across the Tibetan plateau. The Tibetan people believe the ladders lead to the Holy Land.

Pasang and the other guides were selected to help shoot the film because most professional videographers lack the skills and endurance to film in the harsh conditions more than 5,000 meters above sea level.

When filming began in 2013, Tashi Wangyel, chief director of photography, chose Pasang to help record the last leg of the climb, starting 7,028 meters above sea level, because of his contribution to the 2008 Olympic torch relay at Qomolangma.

Last year, after four months of camera training, Pasang and fellow guides were dispatched to finish the documentary.

According to Tashi, the best time to climb Qomolangma is a window stretching from March to May each year. The crew waited at base camp for three months before the opportunity presented itself.

On May 25, last year, having collected and analyzed data provided by the China Meteorological Administration and the Meteorological Bureau of the Tibetan Autonomous Region, Pasang and his partner set off before dawn.

Severe cold made filming extremely difficult. "The equipment weighed more than 5 kilos," Tashi said. "The Tibetan cameraman carried more than 10 kilos of camera and gear, plus an oxygen bottle and thermal gear."

The need to keep the batteries charged and in working condition, while also trying to capture difficult time lapses along the steep and glazed slope made the task almost impossible, Tashi said.

But the two Tibetan cameramen spent six hours a day recording the starry sky, capturing the changes between light and dark above the peak.

The air at their base camp, at 5,200 meters, contained only half the oxygen available at sea-level, and the higher they climbed, the thinner the air became.

"I could hear the beating if my heart clearly," Pasang recalled. "I was constantly out of breath. As we reached 8,000 meters, we put the camera on the ground and pushed it forward."

After six hours, Pasang and his partner became the first Chinese cameramen to carry a tripod to the summit of Qomolangma, where they stopped filming.

They stayed on the summit for 20 minutes, capturing precious images from the roof of the world, but Pasang was not confident, and he worried about the quality of the video.

"He even felt ashamed, and stopped at 6,000 meters on the way back," Tashi said. "He refused to return to camp at 5,200 meters."

The assistant director and the chief cameraman had to be dispatched to persuade him to return.

"When the video was played at the camp, we found it was good enough." Tashi said, although he admitted there are flaws.

"The focus control, the stability of the lens, the variety of the scenery and the lack of brightness were still unsatisfactory in the final version," Tashi said.

Despite its rough edges, Himalaya: Ladder to Paradise has crested the 6 million yuan ($938,000) mark since it was released nationwide in mid-October.

"It is successful enough, given the pressure of domestic and foreign commercial movies," said Tashi, who believes the movie will achieve the biggest audience for any Chinese documentary.

The film crew was also the first in the industry to capture footage at altitudes higher than 6,500 meters.

"Some of the scenery shots were finished by our crew, who also took risks," Tashi said.

During a windstorm, the chief cameraman's eyeglasses were blown off his face, and he slid 8 meters down the slope, unable to see.

"If not for the tent of another mountaineering team, he would have fallen into a chasm," Tashi recalled.

The documentary has been purchased by the BBC and Japan's NHK for screening overseas. The production team has also finished post-editing a five-episode television series, although Tashi did not reveal the release date.

The experience gave Pasang a taste for filming and inspired him to begin shooting on his own. "It changed my life," he said.