Old Master Paintings specialist Jonquil O’Reilly uses fashion to reveal the wider context of paintings. In her debut video, ‘The Costumist’ introduces Barbara Schwarz, wife of  Matthäus Schwarz, a fascinating 16th-century personality who meticulously documented his favourite outfits in a ‘Trachtenbuch’ or costume book. Despite her exclusion, Christoph Amberger captured a portrait of the Augsburg society woman and her highly fashionable costume, a highlight of Sotheby’s upcoming Old Masters Evening sale on 5 July in London.