Selected works from the past four years have been brought together for Wolfgang Tillmans’s exhibition “Aufsicht”/“View from Above,” traveling to four venues across Europe. In Hamburg a group of earlier works was added, perhaps in honor of the artist’s onetime residence here. But the emphasis was on his most recent abstractions—works that play with light or that are actually drawn with traces of light. Great quantities of work from the series “Blushes,” 2000, “Conquistador,” 2000, and “Mental Pictures,” 2000–2001, filled the walls. Tillmans’s typical way of repeating motifs in varying formats