Anna Wintour says Mario Testino can make "insecure" people feel "beautiful".Anna Wintour has praised photographer Mario Testino for making his subjects look "as beautiful as possible".The editor of American Vogue has used Testino for several of the magazine's high-profile covers, such as Lady Gaga and Sienna Miller's shoots.Wintour says Testino was an obvious choice for her, due to his ability to make people look their best."I think Mario's kind of dedicated his life to surrounding himself with beauty in so many forms, and I think that one of his great skills as a photographer is making people look as beautiful and extraordinary as they possibly could," she gushed to Fashionista."I think that for celebrities and people that can sometimes be insecure about the way they present themselves, Mario's hands are the most reassuring to be in, because they know that they're safe, they know that they will look as beautiful and extraordinary as they possibly can, and so he's able to capture candid moments and they know that even if they let their guard down, they're going to look extraordinary."Testino rose to fame all over the world for his intimate shots of the British Royal Family, including late Princess Diana's infamous Vanity Fair photoshoot.Last night Testino opened his first US gallery at the Museum of Fine Arts in Boston.The exhibition is split into two, In Your Face and British Royal Portraits, with the former showing the 'boldness' in his work and the latter showcasing 16 of Testino's favourite royal family shots.Testino explained Wintour had a huge amount of input into the finished product."I totally listen to her and follow her," he explained. "She's the most loyal person there is."