in the case of potential betrothals, when the object of the work is to make the sitter as attractive as possible. In these cases the sitter was often shown smiling, with an engaging and radiant expression designed to appeal to her intended. Around 1508, Albrecht Dürer described the function of portraiture as "preserving a person's appearance after his death". Portraits were objects of status, and served to ensure that the individual's personal success was recorded and would endure beyond his lifetime. Most portraits tended to show royalty, the upper nobility or princes of the church. The new affluence in the Burgundian Netherlands brought a wider variety of clientele, as members of the upper middle class could now afford to commission a portrait. As a result, more is known about the appearance and dress of the region's people than at any time since the late Roman period. Portraits did not generally require lengthy sittings; typically a series of preparatory drawings were used to flesh out the final panel. Very few of these drawings survive, a notable exception being van Eyck's study for his Portrait of Cardinal Niccolò Albergati. Landscape Landscape was a secondary concern to Netherlandish painters before the mid 1460s. Geographical settings were rare and when they did appear usually consisted of glimpses through open windows or arcades. They were rarely based on actual locations; the settings tended to be largely imagined, designed to suit the thematic thrust of the panel. Because most of the works were donor portraits, very often the landscapes were tame, controlled and served merely to provide a harmonious setting for the idealised interior space. In this, the northern artists lagged behind their Italian counterparts who were already placing their sitters within geographically identifiable and closely described landscapes. Some of the northern landscapes are highly detailed and notable in their own right, including van Eyck's unsentimental c. 1430 Crucifixion and Last Judgement diptych and van der Weyden's widely copied 1435–1440 Saint Luke Drawing the Virgin. Van Eyck was almost certainly influenced by the Labours of the Months landscapes the Limbourg brothers painted for the Très Riches Heures du Duc de Berry. The influence can be seen in the illuminations painted in the Turin-Milan Hours, which show rich landscapes in the tiny bas de page scenes. These, according to Pächt, should be defined as early examples of Netherlandish landscape painting. The landscape tradition in illuminated manuscripts would