Portraits of power - Telegraph With only one hour, he took photographs rather than sketched. I described to her the reflective mood I wanted the painting to convey; I wanted her to have it in her mind, so it was visible on her face. She was a fantastic sitter, she knew what I wanted, and she's actually very beautiful to paint - I hadn't expected that. As a setting, Buckingham Palace didn't appeal. I felt [it] was limited in terms of telling real stories. I had three locations in mind, but the one I really wished for came through. He won't be drawn on which, save to say it's "an obvious choice, very fitting. It's laden with extraordinary power - there isn't a place more beautiful in this country. Heimans, who has a portfolio of paintings reaching back nearly 25 years, is renowned for portraits that integrate subject and context. When he painted Princess Mary of Denmark in 2005, he set her in the Garden Room of the Frederiksborg Palace rather than the formal state rooms, and included a nod to her home town of Hobart, Australia, in the form of a painting of its city hall reflected in the mirror. "When you have a complex image you are drawn into the entire narrative."" he says. He grew up in Cremorne and Mosman, middle-class suburbs on Sydney's North Shore. His father Frank was a documentary maker, his mother Rosette a French teacher. "Even as a child I had a confidence in myself artistically," he says. It took his parents "a bit of time" to come round. I went to university in part to appease that. As soon as they saw I could potentially earn a living they felt slightly reassured. Although he graduated in maths and fine art, he started with architecture; it was his architecture tutor that gave him his first commission. Aged 18 I had a string of commissions and architecture became my fall-back. It was ridiculous: no one does a six year degree as fall-back. He liked maths though: "it has a beauty and elegance...It's left in me an intuitive understanding of perspective." Art school wasn't for him. I came to Europe to look for a school but it was an awkward time, the late 80s, there was a current of non-education in the arts, very theoretical and I felt I wanted a strong, technical grounding. Realistic portraits were quite uncommon and even somewhat denigrated. As well as attending a Sydney academy to learn traditional methods, he took lessons with a private teacher, "a very old Polish man who had learnt to paint at the academy in Krakow just after the war, when things were very serious in the eastern bloc. I built my own technique based on that and looking at other art. If I'm looking at a painting I can work out how the painter has achieved those effects. By the late Nineties, he had established himself as one of Australia's foremost young portraitists. Several of his works from this period, when he was only in his twenties, now hang in the National Portrait Gallery of Australia. Since then, commissions have included Dame Elisabeth Murdoch, former Australian prime minister Paul Keating, an English QC, even the French rugby team. He is also a favourite with bankers in New York and London. Last year he painted the legendary Russian conductor Vladimir Ashkenazy at Sydney Opera House. The portrait was lauded internationally for its unusual perspective, where Ashkenazy is positioned amongst a riot of architectural detail. It's a clever piece, a sort of visual fugue, held together by light, reflection and geometry. When I visit the studio, the Ashkenazy is leaning against a wall opposite its packing case. There's a boot print on its surface, where a particularly careless handler walked over it during transportation. And not just any boot; this must be a size 15. Heimans is about three weeks shy of his Royal deadline, and feeling the pressure. It's twice as big as any other painting I've done, more than twice the amount of work. His commissions usually take about 12 months, this must be completed in six months. He works 10 hours a day, every day. You can't do it in little chunks. If you're writing an email here and picking up the phone there, you're screwed. He listens to classical music "the romantics, a lot of chamber music." Recently, he's developed a taste for lectures on the kings and queens of England - "all that history is feeding into the painting." His technical approach pays homage to masters of chiaroscuro such as Caravaggio and Rembrandt, adopting a traditional glaze technique rarely seen in modern portraiture. There might be 10 coats, more for the lights; the shadows tend to be more transparent. In the flesh it seems the light is sitting in between the layers rather than on the surface. It gives the paint an opalescent quality. I use heavy mediums which trap the light, so it refracts from every layer... the final coat is everything, where the magic starts to appear. It's quite satisfying to reach that point because you can see all the preparation was worthwhile. Meanwhile, the commissions are rolling in: "A couple in Australia, one for a medical research team, a series of private commissions for Hong Kong, and a UK-based family, very high profile." He looks so tired that I ask him if the painting is keeping him awake at night. It is. As are his two small babies. "I think I'll follow the painting to Australia when it goes," he says. I'll have a break there. That's one of the things I look forward to - the simple pleasure of lying on a beach.