Don't ask your models to pose. That is one of Jock Sturges' secrets to good photography.

The American photographer, who has been known for works of naturism since the 1990s, has brought a selection of his signature photography to China this fall.

Some 60 black-and-white portraits that stilled the musing, laughing, wondering subjects in their most unguarded, natural state are on display at the 798 Wuyue Image Space.

With them, the artist hopes to convey his persistent attitude when taking pictures.

"The best pictures are the true ones," he says. "The hardest part of photography isn't mechanical. It's what the photographer knows about the subject."

There is only one way to get that in-depth understanding.

"Time, time, time," Sturges says. The 66-year-old's most famous series tracked a young girl, Misty Dawn, through her childhood, adolescence and 20s.

"Ninety-nine percent of my time is spent socializing. Taking the pictures is only a few seconds."

To illustrate further, Sturges says he needs at least three years to get a decent picture that's "truly meaningful".

"They have to trust me, and I trust them. It has to take that long before there is a relationship."

Therefore, for the Rollei Project filmed with the title camera and stretched for three months in 2012, the subjects are understandably those whom Sturges knows very well - including his daughter, his daughter's best friends and long-time neighbors.

Most of them are naturalists. And they bare themselves to Sturges, both their bodies and inner selves.

With that familiarity, the photographer can do away with wasted film. "I only take one shot of each picture I take," he says.

He boasts the ability to find the relationship between any photographer and subjects.

Taking one of his own pictures as example, where two little ones stare curiously and without smiling into the camera, Sturges expresses his dissatisfaction with it.

"We've known each other for only a year. You can see it in their eyes that they're still a little on guard. But I'll do another one next year, and it will get better."

With forming sincere relationships as his aim, it's easy for him to point out the pictures that will have a lasting impression, too. "It's the human relationship that touches, not sugar and surface beauty. That's why you put away magazines," he says.

Tian Zhili, the curator, has arranged all the pictures in an album in the studio, a first for Sturges' pictures.

"Each of the photos are so innocent and intimate, I don't want to ditch any single piece," Tian says.

"Sturges' works are classic, simple, direct and so charming that one is always moved at the sight of them. They're the presentations of life."