It's a choice - there are two different sorts of photographer: those obsessed with the technicalities and those obsessed by the subject.

I waited a long time, an hour or two, to make that picture perfect. 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. I took my camera and that was the picture that ran everywhere - it was spontaneous emotion you could see they were completely in love.

I had the right amount of detachment to go back and really appreciate what I had grown up with. There’s a particular style that is very Peru that you don’t see anywhere else; it’s got so many different imprints. When you mix Incan minimalism with the heavy, ornate Spanish Baroque, it is very interesting.

My favourite subjects at school were algebra and logic: making a big problem into something small.

Ive been criticised for pretty, smiley photographs, but at least someone is happy! In my mind, I am always giving the image to the sitter.

There is something about Prince William and Prince Harry that brings real modernity to the British royal family. They are also very open, human, and kind, and this is what I have tried to capture in the pictures I have taken of them as well as in my pictures of Prince William and Catherine.

The more I photograph women, the less it is about transformation. Women are beautiful. All that really matters is enhancing that.