Judith and her Maidservant, c.1615-17, oil on canvas, 114 x 93.5 cm. Galleria Palatina, Palazzo Pitti Baroque art, particularly history paintings, sought to capture the decisive moment.

That's what an art preservationist is arguing, based on trace materials found in the Baroque master's canvases ... project images of their subjects onto canvas, which they would then trace.