Legendary photographer Mario Testino has photographed some of the world's biggest stars from the world of fashion, Hollywood and royal houses. Now, the Peruvian shutterbug has opened up about his experience behind the lens, revealing that the process of photographing royals is quite similar to that of nudes.

TAP FOR GALLERY Mario Testino says that photographing royals is quite like photographing nudes.

“I see both nudes and portraits of royals as basic things in life,” he told Vanity Fair's Derek Blasberg, adding, “The royals seem to be, especially in countries such as England and Denmark, a constant—families that have existed as part of the country for a very, very long time. They are like the essence of the country. And a nude is like the essence of a human being. So even though they appear quite different, they have a similarity. They represent something fundamental that inspires me, and which I apply to my work in different ways.”

Here, Mario snaps photos of the Duchess of Cornwall at a charity reception in 2013.

Throughout his storied career, Mario has photographed royals from a variety of monarchies, including the United Kingdom. He was a close friend of the late Princess Diana, and in recent years has become the Duke and Duchess of Cambridge's go-to photographer for milestone events in their family. He famously shot Prince William and Kate's engagement photos in 2010 and had the pleasure of capturing Princess Charlotte's christening last July.

The Royal Family pose for Mario following Princess Charlotte's christening.

He further explained to the publication, “In fashion photography, we are free to create whatever we want to ... With royalty, it is not so much about new looks and all the other elements of a fashion photograph. It is about capturing and documenting something that exists. It is about making it look its best, capturing something at its core, and making it look fresh in order to communicate what is behind the people."

The shutterbug photographed Princess Diana many times before her tragic passing in 1997.

And when it comes to creating a great royal portrait, Mario says the secret is fresh eyes. "The Royals came to me initially for a commission of Princess Diana, and since then they have asked me for some other commissions. I like to keep looking at these commissions with fresh eyes—not based on what was done before, but what inspires me now. That is why I enjoy doing them.”