Kate Middleton

By Joanna Crawley On January 19, 2014

Renowned photographer Mario Testino has opened up on shooting Kate Middleton, the Duchess of Cambridge and Prince William for their official engagement pictures in 2010, revealing that the royal couple are "completely in love".

Testino photographed Kate and William in November 2010, weeks after the couple confirmed their engagement. It sounds like it took perfectionist Mario awhile to land the best shot though, with the snapper telling The Telegraph:

"You could see they were completely in love. I waited a long time, an hour or two, to make that picture perfect," he said of their engagement session in the Council Chamber linked to Clarence House (where Prince Charles resides). "But I wasn't totally satisfied."

"Then, when I'd finished the shoot, they were about to leave and they suddenly hugged in front of a radiator," he recalled. "I took my camera and that was the picture that ran everywhere -- it was spontaneous emotion ... you could see they were completely in love."

On the duchess' much talked about looks and comparisons to William's mother Princess Diana (who he also snapped), the photographer muses: "Kate, she is beautiful in a different way. She radiates happiness. She is comfortable in her love."

Testino also opened up on other members of the royal family that he's photographed, revealing that 29-year-old Prince Harry was "so like Prince Charles: they act alike, they have the same sense of humor, the same confidence."

The photographer added that Harry's older brother William, 31, however, was "more like his mother, there's a kindness and a gentleness there that instantly wins you over."