The collection contains an estimated 300,000 photo prints. The 1923 photogram, 4/i/Lampe Heliokonstruktion 125 Volt by El Lissitzky and Vilmos Húszar, is a special and rather atypical example, which at the same time illustrates the value of the photo collection as a primary source. The work is part of the estate of architect and urban planner Cornelis van Eesteren who was in the De Stijl circle.