Clue: Warhol being, to some extent, portraitist (7)
Answer: HOLBEIN
Explanation: Definition: portraitist
A hidden answer ('to some extent') in 'War**HOL BEIN**g', for a family of painters, most notably Hans HOLBEIN the Younger, perhaps best known for his portraits of Henry VIII (and *The Ambassadors* with its anamorphic skull)*.