Leonardo didn't have a photograph to work from.

Does the Guardian not have an editor?
From the article: "Stamping out copyright infringement is harder than the old men in suits thinks it is."
Followed immediately by: "It's all the rage these days: crackpot proposals. . ."
Later, ". . .perform with near-perfection: even if it turns out. . ."
There may be more but I stopped looking. Sorry about the non sequitur but it's weird to see errors like this in the (online) print of a popular newspaper. :P