A public princess

It might look like a paparazzi shot, snapped unawares in the long grass by the river. In fact, this sanctioned portrait catches the newlyweds in casual mode in Balmoral at the end of their August 1981 honeymoon. Charles looks at home in the Scottish setting. His wife, by contrast, appears to have one foot firmly planted in Sloane Square. Photograph: Hulton-Deutsch collection/Corbis

The princess meets and greets the crowds at the Open Expo in Canada. The only person apparently unimpressed is the Liliputian tyke with the oversized spectacles. Probably a budding republican. Photograph: Corbis

East meets west during a visit to Abu Dhabi, May 1989. Photograph: PA Wire/PA

Diana in sombre mode, shrouded by a black veiled hat during a trip to the Birthright Centre in Sheffield hospital, April 1986. With its heightened - almost theatrical - air of gloom, it is a classic image of 80s style. Photograph: Jayne Fincher/Princess Diana Archive/Getty

Another sober side to the princess, this time accompanying Charles to Arlington military cemetery on a chill November day in 1985. It was during the course of this US tour that Ronald Reagan, his mind wandering, famously introduced her as "Princess David". Photograph: Jean Louis Atlan/Sygma/Corbis

Diana congratulates a victorious Charles at the end of a polo match in 1988. At the time the image was seized on by the press as evidence of a happy, healthy relationship. In fact, the marriage was already starting to sour. Photograph: AP/PA