He had to cleanse himself and did not consume garlic or shallots before painting.

During the painting process, thangka painters were also not allowed any contact with women.

As of now, Losang Changchub doesn't have any apprentice learning from him because he says young people may not be able to endure painting for three months to complete a small piece of thangka. Typically, a big piece can take several years to complete.

"It's said that it took a whole day for Namkhagyan to draw a single leaf," he says.

Also on display at the exhibition are about 60 other thangka paintings done in the Namkhagyan style by his successors from his hometown, where thangka painting techniques are passed from fathers to sons.

Song Bin, the organizer of the show, says the art of Namkhagyan's thangka has long been neglected due to its low exposure to the public.

Song is now preparing to set up a school in Luhuo county to allow more people learn Namkhagyan-style thangka.

If you go

9 am-5 pm, through Thursday. National Center for the Performing Arts, 2 West Chang'an Street, Xicheng district, Beijing. 010-6655-0000.