By the end of the century aristocratic, or French, values were spreading among the burghers, and depictions were allowed more freedom and display. A distinctive type of painting, combining elements of the portrait, history, and genre painting was the tronie. This was usually a half-length of a single figure which concentrated on capturing an unusual mood or expression. The actual identity of the model was not supposed to be important, but they might represent a historical figure and be in exotic or historic costume. Jan Lievens and Rembrandt, many of whose self-portraits are also tronies (especially his etched ones), were among those who developed the genre. Family portraits tended, as in Flanders, to be set outdoors in gardens, but without an extensive view as later in England, and to be relatively informal in dress and mood. Group portraits, largely a Dutch invention, were popular among the large numbers of civic associations that were a notable part of Dutch life, such as the officers of a city's schutterij or militia guards, boards of trustees and regents of guilds and charitable foundations and the like. Especially in the first half of the century, portraits were very formal and stiff in composition. Groups were often seated around a table, each person looking at the viewer. Much attention was paid to fine details in clothing, and where applicable, to furniture and other signs of a person's position in society. Later in the century groups became livelier and colours brighter. Rembrandt's "Syndics of the Drapers' Guild" is a subtle treatment of a group round a table. Scientists often posed with instruments and objects of their study around them. Physicians sometimes posed together around a cadaver, a so-called 'Anatomical Lesson', the most famous one being Rembrandt's "Anatomy Lesson of Dr. Nicolaes Tulp" (1632, Mauritshuis, The Hague). Boards of trustees in their "regentenstuk" portraits preferred an image of austerity and humility, posing in dark clothing (which by its refinement testified to their prominent standing in society), often seated around a table, with solemn expressions on their faces. Most militia group portraits were commissioned in Haarlem and Amsterdam, and were much more flamboyant and relaxed or even boisterous than other types of portraits, as well as much larger. Early examples showed them dining, but later groups showed most figures standing for a more dynamic composition. Rembrandt's famous "The Militia Company of Captain Frans Banning Cocq" better known as the "Night Watch" (1642), was an ambitious and not entirely successful attempt to show a group in action, setting out for a patrol or parade, also innovative in avoiding the typical very wide format of such works.