The Light on Van Doesburg Workshop The Light on Van Doesburg Workshop

Colour, and the relationship of colours to each other, are important themes in Theo van Doesburg's design drawings. If certain colours fade, the whole design changes. Light is needed to see a work, but light causes damage. This damage is often cumulative and irreparable, even with small amounts of light. A few hours of sunlight or a few years of museum lighting can make light-sensitive materials disappear altogether. Het Nieuwe Instituut is aware of its responsibility to ensure that these works remain representative of the vision of Van Doesburg, without loss of colour.

A producer looks at exhibiting a collection piece in a different way from a collection manager, which is why various stakeholders from the institute, together with restoration and conservation experts from the RCE, and led by senior researcher Agnes Brokerhof (RCE), have laid the foundation for the lighting policy in teams. The four works shown above from the Van Doesburg collection have been selected for this workshop. Readability plays an important role here: they show the design process and therefore have a high information value for researchers and others.

Various questions have been explored, such as: what is the value of an object or collection? What happens to the value if the material changes? How much change is acceptable over a period of time? And how sensitive is the material? The policy will translate into a series of agreements, including a lighting budget, and the recommended number of lux hours per year.

Of the four selected works, the drawings on which Van Doesburg mainly worked himself were awarded the highest artistic and historical value. His gouache on tracing paper, unique in its design and coloured by himself, received a higher rating than the diazotype on vellum, the original drawing of which was made by Denis Honegger (Van Doesburg drew only on the copy). The drawing of graphite and India ink on vellum was valued for its simple beauty. Reproductions, such as the diazotype and blueprint (cyanotype), of which there are usually several copies, also within the institute's collection, were given a lower rating.

To see how changes over time affect the valuation, the RCE created a Photoshop simulation of the digitised object, based on the expected light sensitivity. In the simulation, reproductions tolerated the least light. With the diazotype, the lines soon faded completely, and the blueprint fades with a shift to purple. As long as the characteristic features remain intact, such as the lines of the diazotype and the blue colour of the blueprint, the decay does not greatly affect the usefulness or value of the material.

When asked about a strategy for showing the copies, the group initially chose to rotate the different versions. When it became clear that the consequence would be that all the versions would deteriorateAgnes Brokerhof, Pieter Kuiper & Steph Scholten (2018) Spread or Sacrifice: Dilemma for Lighting Policies, Studies in Conservation, 63:sup1, 28-34, DOI: 10.1080/00393630.2018.1504439, the consensus changed. One choice isn't necessarily better than the other, but it's good to establish the tipping point from acceptable to unacceptable change.

Also interesting is the drawing on vellum, in which the browning of the medium can increase the sense of age and historical experience. The lines of the ink and graphite will hardly change under the influence of light. There is a slight reduction in contrast, but it has little effect on readability and value over the years.

Light will have relatively little effect on the gouache coloured drawing. Earlier researchLuc Megens, Rika Pause, Mariel Polman, Onderzoek van de pigmenten in de kleurontwerpen van Theo van Doesburg voor de Aubette in Straatsburg, [Investigation of the Pigments in the Colour Designs of Theo Van Doesburg for the Aubette In Strasbourg,] Cultural Heritage Agency, November 9, 2019 on a comparable work showed that Van Doesburg used paints with fairly light-fast pigments. The poor adhesion of the paint to a surface that is actually unsuitable and which will eventually yellow is actually expected to cause more damage. Paint loss is unacceptable according to the group. This work would therefore not be currently suitable for consulting or exhibiting, but would first have to be conserved.

This workshop prepared the ground for the joint development of a lighting policy, including a lighting plan for exhibitions and a loan protocol. In order to draw up a policy for the entire Van Doesburg collection, it will be divided into categories of drawings on which light probably has the same effect. The fragility and value of the underlying works are also important here.

As a result of this workshop, the desire arose to conduct more light research on reproductions. This will take place within _Invented from Copies_, one of the research projects of Disclosing Architecture. There will be a follow-up in 2022.

A prominent position in the Disclosing Architecture programme is reserved for the collection of Theo van Doesburg (1883-1931). As an architect, artist and founder of the De Stijl artists' movement, Van Doesburg has acquired a special cultural-historical value within the National Collection for Dutch Architecture and Urban Planning, in particular because of his views on colour and architecture. Worldwide, Het Nieuwe Instituut owns the largest part of his architecture collection, which shows his design process and the history of the ideas behind it.

This article draws on the report of the Light on Van Doesburg WorkshopBrokerhof, A.W., 2021, Workshop Licht op Van Doesburg [ Light on Van Doesburg, Workshop] RCE project number 2021-024, Amsterdam, Cultural Heritage Agency, National Heritage Laboratory. of the Cultural Heritage Agency of the Netherlands (RCE).