A new exhibition in Belgium brings together a 1956 painting by Paul Delvaux and its original preparatory drawing, revealing how the artist transformed his composition and concealed elements beneath the finished work.

Scientific examination of a painting by Belgian surrealist Paul Delvaux has revealed significant changes to its original composition, including figures and other details concealed beneath layers of paint. The findings are being presented in a new exhibition opening on 16 October at Musée L in Louvain-la-Neuve.

The exhibition, La Ville lunaire II: The Hidden Side of Paul Delvaux’s Painting, examines a work completed in 1956 and held in the museum’s permanent collection. Through X-ray imaging, infrared reflectography and ultraviolet examination, researchers have been able to investigate the artist’s working methods and compare the finished painting with an original preparatory drawing.

The exhibition, which runs until 7 February 2027, follows the acquisition of the drawing by the King Baudouin Foundation in 2024. Its subsequent deposit at Musée L has made it possible to examine the two works together and reconstruct the development of a composition that underwent substantial alterations.

A Painting Concealing Its Own History

Completed in June 1956, La Ville lunaire II depicts a mysterious nocturnal landscape, with a long avenue, buildings, streetlamps and figures arranged within an unsettling architectural setting.

The painting measures approximately 89 by 139 centimetres and was executed in oil on a fibreboard panel. It entered the museum’s collection in 1990 through a bequest from Dr Charles Delsemme.

Its carefully constructed perspective and unusual treatment of space reflect Delvaux’s interest in creating scenes that appear familiar while remaining detached from ordinary reality.

The museum’s collection records describe the work as a strange nocturnal landscape, with wooden barriers and a sequence of streetlamps establishing its distinctive spatial arrangement.

Yet the painting visible today differs considerably from the composition Delvaux originally envisaged.

Earlier technical examinations had already established that important details were covered during the painting process. The new exhibition brings those findings into direct comparison with the preparatory drawing, enabling visitors to see how the artist’s intentions changed.

An auction catalogue published in 2024 identified several elements present in the drawing and concealed in the painting, including a moon in the right-hand sky, a seated figure on the right and two figures wearing robes near the centre.

These changes are significant because they suggest that Delvaux did more than adjust minor details. He altered the population and lighting of the scene, potentially changing how the composition would be experienced by the viewer.

The reasons for those decisions remain uncertain.

How Scientific Technology Reveals Hidden Paintings

Modern conservation techniques allow researchers to examine works of art without removing the paint that covers earlier stages of their creation.

Infrared reflectography can reveal underdrawings and certain changes concealed beneath surface paint, depending on the materials used by the artist. X-ray imaging can detect differences in the composition of pigments and structures below the visible surface.

Ultraviolet examination provides further information about surface materials and alterations, including some later interventions.

When combined with documentary evidence, these methods help researchers distinguish between an artist’s initial design, revisions made during painting and changes introduced after completion.

The Musée L exhibition uses these techniques to investigate what art historians call pentimenti — visible or detectable alterations that record an artist changing their mind during the creative process.

The preparatory drawing, measuring approximately 28 by 45 centimetres, provides an additional reference point. Executed in ink and pencil, it contains elements that were subsequently revised or painted over in the final composition.

Displayed alongside the finished work, it allows visitors to follow the artist’s decisions from the preliminary design to the version that eventually entered the museum’s collection.

The technical findings also demonstrate the importance of preserving preparatory studies, which can contain information absent from completed paintings.

Paul Delvaux and the Belgian Surrealist Tradition

Born in Antheit in 1897, Paul Delvaux became one of Belgium’s best-known twentieth-century painters, developing a distinctive artistic language associated with surrealism.

His paintings frequently depict classical buildings, railway stations, deserted streets and solitary figures, often arranged in environments where architectural precision contrasts with an atmosphere of uncertainty.

He was influenced by the Italian painter Giorgio de Chirico, whose deserted urban spaces and dramatic perspectives helped establish the visual language of metaphysical painting.

Delvaux’s relationship with de Chirico has been examined extensively by art historians, including Joël Roucloux, whose study of La Ville lunaire II analysed its architectural perspective, shadows and the psychological effect of its composition.

The painting’s apparently moonlit setting is particularly interesting in light of the concealed moon identified by technical examination.

The absence of that celestial body from the final visible composition changes the relationship between the painting’s title and its visual content, leaving the viewer to interpret the source of its unusual illumination.

This approach distinguishes Delvaux from other Belgian surrealists, including René Magritte, whose work frequently relied on recognisable objects placed in logically contradictory situations.

For Delvaux, architecture, perspective and the arrangement of human figures were equally important in constructing a world that appears coherent but resists conventional interpretation.

A New Examination of a Familiar Work

The exhibition forms part of Musée L’s programme devoted to research into its permanent collections, rather than a conventional retrospective of the artist’s career.

Its central purpose is to explain how a single painting developed, from its first drawn composition through successive revisions to its completed form.

The research has been supported by the Jacqueline Delcourt-Nonkels Fund, managed by the King Baudouin Foundation.

For visitors, the opportunity is to examine not only a painting by one of Belgium’s leading surrealists, but also the evidence of the artistic decisions that shaped it.

The exhibition is open at Musée L in Louvain-la-Neuve from 16 October 2026 to 7 February 2027. By presenting the original drawing, technical images and finished painting together, the museum offers a detailed examination of Delvaux’s methods and the changes he made to one of his most carefully constructed nocturnal scenes.