Amid the absences of the Princess of Wales and King Charles, royal expert Professor Anna Whitelock says that "monarchs have to be seen, visibility is their currency, it's where they get their legitimacy from" -- and she notes that Kate "seems to be being held to the same standards". The prevalence of images of Charles since his cancer diagnosis shows he's understood that he "still needs to be present through image", says Whitelock, professor of the history of monarchy at City, University of London. IMAGES AND SOUNDBITES