A royal photographer is spilling behind-the-scenes details on what some of the world’s most glamorous princesses were like away from the cameras.

In his new book, My Life Photographing Royalty And The Famous, Reginald Davis, who worked as a royal photographer for four decades, reveals a more intimate side to the last century’s most famous royals.

But “the most difficult royal I ever photographed,” he said, according to the Daily Express, was Princess Grace of Monaco.”

“She only agreed to a private audience because I had previously had a private audience with the Queen,” he continued.

“Everyone wanted to shoot Grace,” he said. “She was such an attractive woman, why be so haughty, arrogant and awkward?

Pictorial Parade/Hulton Archive/Getty

“Of course, you’d never know that from looking at her face” he said. “(In the photo) she seems every inch the relaxed, happy mother.”

As for his favorite subject to shoot, Davis says that title went to Queen Elizabeth’s younger sister, Princess Margaret.

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“She was just so vibrant — and had these beautiful azure eyes,” he said. “She really was the Diana of her day. Everything I took of her was in demand.”

After training as a photographer with the Royal Navy during WWII, Davis joined the Daily Express in 1949 and graduated from working on the night shift to shooting celebrities at first nights and film premieres.

He first photographed the Queen in 1959 and during the next four decades, accompanied the royal family on state visits and royal tours around the world.

But he did some of his best work at the royal family’s homes in Britain.

Lichfield

“I’d been invited to Windsor Castle to photograph the family in the gardens. I had this idea of sitting them all on the grass.

“But the ground was so wet I had to get something for them to sit on,” Davis said. “All I could find was a Persian rug.

“When Prince Philip saw it he wanted to know: ‘Whatever is a Persian carpet doing in the middle of Windsor?’

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“Thankfully the Queen eased the situation, saying to the two younger boys (Princes Andrew and Edward): ‘Come along children, let’s sit on the magic carpet and fly away …’ “

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