Not much is known about the artist of the original painting, François Gérard.  He was one of the
major students of Jacques-Louis David and a key voice of early 19th-century art in Paris.

 The person, who has been working on Gérard's catalogue raisonné for the last 30 years,  is a corrupt dealer.  Therefore, any conclusions that he has drawn are suspicious.

(The pictures and information were kindly provided by Ralph Rosen, a professor of classical studies at University of Pennsylvania, and Jon Seydl at the Getty respectively)