AMSTERDAM.- In collaboration with the Museum Prinsenhof Delft, the Rijksmuseum has conducted the first ever extensive technical research into the work of Pieter de Hooch (1629-in or after 1679), in the run-up to the 'Pieter de Hooch in Delft: From the shadow of Vermeer' exhibition at the Museum Prinsenhof Delft (11 October 2019 through 16 February 2020). This study has deepened our understanding of Pieter de Hooch’s working method, his search for the right composition, his growth as an artist, and his palette.

Janelle Moerman, director of the Museum Prinsenhof Delft: In 2017, the Museum Prinsenhof Delft initiated a major multidisciplinary research project on Pieter de Hooch. Such an extensive study of this Delft master had never before been undertaken. The Rijksmuseum was our most important research partner in this project and also the most important source of works on loan for this exhibition, with as many as four paintings. Thanks to this research project, we now know more than ever about Pieter de Hooch. We are extremely grateful to the Rijksmuseum for their generous contribution to the exhibition.

Taco Dibbits, general director of the Rijksmuseum: This research has increased our understanding of how De Hooch built up his paintings, and it has created an excellent basis for further studies in the future. I’m delighted the Rijksmuseum has been able to make a contribution to this must-see exhibition at the Museum Prinsenhof Delft.

Research
Over the past 18 months, researchers gathered technical information on a total of 27 paintings from all over the world, and used advanced imaging techniques such as macro-XRF scanning (MA-XRF) and reflectance imaging spectroscopy (RIS/VNIR) to look ‘under the skin’ of ten of them. Conservator Anna Krekeler led the research, which was carried out at the Rijksmuseum’s Atelier Building.

New insights
The search for the right composition and hidden scenes
Using MA-XRF researchers have been able to confirm that on many occasions Pieter de Hooch made changes to figures in his paintings in his search for the ideal composition. It has been revealed, for example, that the artist made alterations to A Mother Delousing her Child's Hair, known as A Mother's Duty (c. 1660-61). The painting initially featured a couple in front of the box-bed. The figures in this newly revealed version are consistent with similar pairings in De Hooch’s Delft paintings, while the room is consistent with paintings he made in Amsterdam. As a result, the work Mother's Duty seems to form a bridge between De Hooch's Delft and Amsterdam periods.

Pieter de Hooch’s growth as an artist
This research has confirmed that it was during his years in Delft, and primarily between 1655 and 1658, that the artist developed most in terms of technique and style. A good example of this is his use of pins with a string attached to achieve perfect perspective: whereas many artists of the period would make use of one tiny pinhole at the central vanishing point on the horizon, two such holes can be found in a number of De Hooch’s paintings. No second pinhole could be found in his paintings dating from about 1658 onwards suggesting, that by this time De Hooch had mastered central perspective.

The artist’s palette
The technical component of the research has enabled researchers, for the first time, to identify the pigments used by Pieter de Hooch. The central conclusion is that in many regards De Hooch’s palette is identical to those of other 17th-century Dutch painters. What is striking is his use of the costly pigment ultramarine produced from the semiprecious stone lapis lazuli. De Hooch used ultramarine in many of his paintings, not only in the prominently blue areas, but also mixed with pigments such as yellow lake to depict green foliage, for example.

The mason’s son who built with paint
The use of the colour of the ground as a shadow or mid-tone, as well as the minimal paint layering De Hooch used to build up the composition, testify to an efficient and economical way of working. Through this research the use of the ground has also become apparent in Figures in a Courtyard behind a House (c. 1663-1665). De Hooch literally built the house, a true mason’s son, brick by brick, with little red brush strokes and using the colour of the ground to indicate the mortar.

Catalogue: Pieter de Hooch in Delft
The catalogue published in collaboration with WBOOKS to accompany the exhibition Pieter de Hooch in Delft: From the shadow of Vermeer includes an essay by Anna Krekeler in which she explores in detail the results of her research.

The Rijksmuseum, international centre of expertise
The Rijksmuseum’s Atelier Building is where the Rijksmuseum, the Cultural Heritage Agency of the Netherlands (RCE) and the University of Amsterdam (UvA) pool their knowledge and expertise on the technical research, restoration and conservation of cultural heritage. This ever-evolving centre of expertise, which brings together research, education and practice under a single roof, is unique in the Netherlands and far beyond its borders.