In a new video from The Telegraph, illustrator Jonny Duddle shows how he goes about creating his illustrations for book covers, using Harry Potter and the Half-Blood Prince as an example. That video, as well as a snippet from the interview, may be viewed below:

“All I can really do, as an artist, is draw my vision of that scene,” Duddle says. His covers were shaped by feedback from Braithwaite, Rowling’s agent Neil Blair and Rowling herself. For each rough he submitted, Duddle would have a number of revisions suggested. He says he could never be sure which of them came from Rowling herself.

Duddle’s covers have been launched sequentially online, where Potter’s enormous fan base is active and vocal. He knows when Bloomsbury have released a new cover because his usually quiet Twitter account is suddenly inundated as the fans give 140-character verdicts.

The biggest complaint he receives, he says, is that Harry looks too young, especially on the cover for the final book, Harry Potter and the Deathly Hallows. “He’s only meant to be 17, and he’s always described as being quite slight. Ron is meant to be tall and skinny. The problem is in the film Daniel Radcliffe and Rupert Grint are grown men by that point, and they’ve been working out.”