Before-and-After and Underneath: Recent Restorations and Technical Examinations of Vermeer's Paintings

In recent decades, a number of Vermeer's paintings have undergone careful technical examination and restoration, often revealing aspects of his art that had been obscured by time, grime, overpainting, or previous restoration efforts. These interventions—sometimes subtle, sometimes transformative—have offered rare insights into the painter's original intentions, compositional changes, and the delicate surfaces he so masterfully crafted. While the idea of restoring a Vermeer may raise anxieties about modern interference, the work carried out by leading conservation teams has generally aimed at returning the paintings as closely as possible to their original state, guided by the highest standards of material analysis and historical understanding.

This article presents a visual and analytical record of several major restorations of Vermeer’s paintings, combining before-and-after image sliders with in-depth commentary on the procedures, findings, and critical responses. From the long-debated cleaning of Girl with a Pearl Earring to the startling revelations uncovered beneath Girl Reading a Letter at an Open Window, each restoration is considered in its own context. These treatments not only affect how we see the paintings today but also how we interpret Vermeer’s working methods, his use of color and light, and his evolving approach to pictorial composition.

Click on the links below to access a before-an-after slider of each painting.

The restoration of Vermeer's paintings focuses on preserving the artwork and revealing its original details and colors. This involves many techniques and advanced tools, such as X-ray fluorescence^{X-ray fluorescence (XRF) is an invaluable non-destructive technique used in the analysis and conservation of paintings, providing detailed insights into the materials and methods employed by artists. By detecting the characteristic X-rays emitted by elements within the paint when exposed to a source of X-rays, XRF identifies the elemental composition of pigments and other materials used in the artwork. This allows researchers to authenticate paintings by comparing the pigments to those historically available and commonly used by the artist. XRF also helps map the distribution of elements across the surface of a painting, revealing underdrawings, pentimenti (changes made by the artist), and the layering techniques used. This detailed mapping is crucial for understanding an artist's process and for making informed decisions during restoration. Additionally, XRF aids in studying the degradation processes affecting paintings, helping conservators choose appropriate restoration materials and techniques that are compatible with the original composition. Although XRF primarily identifies elements rather than complex compounds, making further analysis sometimes necessary, it remains an essential tool for preserving artworks and enhancing our understanding of historical paintings.} and infrared reflectography^{Infrared reflectography (IRR) is a non-invasive imaging technique used in art conservation and research to reveal underdrawings, preparatory sketches, and compositional changes hidden beneath a painting's visible surface. By utilizing infrared light, which penetrates paint layers but is absorbed by carbon-based materials like charcoal, IRR can uncover the artist's original concepts and modifications, known as pentimenti, offering valuable insights into their creative process. This method is also crucial for authentication and conservation, helping to identify areas of damage, previous restorations, and underlying structures that inform restoration strategies. While particularly effective with carbon-based pigments and materials that allow infrared light penetration, IRR may be less useful with other materials, making it a specialized but essential tool for preserving and understanding historical artworks.} Paintings are carefully cleaned to remove dirt and yellowed varnish. Tears are fixed and weak areas are repaired. Inpainting and retoruching fills in missing or damaged areas using reversible materials. Restoration, however, often involves ethical considerations, such as balancing preservation with maintaining the artwork's aesthetic appearance, using reversible materials for future undoing or redoing, and ensuring the authenticity of the original work remains intact.^{Restoration, as it applies to painting, is the process of preserving and repairing artworks to return them to their original or near-original state, while maintaining the integrity and authenticity of the piece. This involves cleaning, stabilizing, and retouching the painting to address damage, deterioration, or the effects of previous restorations, all while using materials and techniques that are reversible and compatible with the original work. The goal of restoration is to enhance the visual appearance of the painting and to prevent further decay, ensuring that the artwork can be appreciated by future generations without compromising its historical and artistic value.}

Diana and her Companions

Diana and her Companions, also known as Diana and Her Nymphs, underwent significant restoration efforts, particularly during the period from 1999 to 2000, which revealed much about the artwork's original state and Vermeer's techniques.

Background of the Painting

Diana and her Companions is considered one of Vermeer's earliest works, painted shortly after he became an independent master in 1653. It features five women, including Diana, the goddess of the hunt, in a serene and contemplative scene. The painting is noted for its large-scale figures and subdued atmosphere, which contrast with the more dynamic and emotional scenes typical of this mythological subject matter.

Provenance and Initial Misattribution

In 1876, the painting was acquired by the Mauritshuis in Paris. Initially, it was misattributed to Nicolaes Maes, a more well-known artist at the time. It was only after further examination that the signature was identified as "JVMeer," confirming it as a work by Vermeer. The painting had been heavily overpainted, including the addition of a blue sky in the background, which was later discovered to be anachronistic, as it contained Prussian blue, a pigment not available during Vermeer's lifetime.^{Prussian blue is a deep blue pigment that was discovered in the early 18th century and became one of the first synthetic pigments widely used in art. It is made from iron salts and has a distinctive, intense color that was particularly popular in painting and printing. Prussian blue is also notable for its permanence and stability, making it a favored choice among artists for creating vivid blue tones.}

Restoration Process

The restoration process involved several steps:

Lining Removal: The 1882 lining of the canvas had deteriorated, prompting the need for relining. This involved applying a protective facing to the front of the painting before removing the old lining, which was done carefully to avoid damaging the original seventeenth-century canvas.

Varnish and Overpaint Removal: The painting had been covered with a yellowed varnish and overpaint that obscured much of Vermeer's original work. These layers were removed using solvents and mechanical techniques, revealing the true colors and details underneath.

Repairing Damage: The original canvas was found to be decayed in some areas, requiring delicate repairs. This included reweaving damaged threads in the canvas and addressing paint losses with new fillings that were then retouched to match the original paint.

Addressing the Blue Sky: The overpainted blue sky was a significant issue. Since removing it entirely risked damaging the underlying paint, the restorers decided to cover it with a dark brown layer, restoring the painting's original closed-off background. This adjustment returned the composition to a state more consistent with Vermeer's other early works.

Retouching and Final Varnish: Retouching was done with great care to ensure that the new work integrated seamlessly with Vermeer's original painting. A final layer of varnish was applied to protect the painting and to restore its visual coherence.

Research and Discoveries

The restoration process also provided insights into Vermeer's technique. For example, the analysis revealed his use of vibrant underpainting to achieve the rich colors seen in the final work. The research confirmed that the blue sky was a later addition and not part of Vermeer's original composition. It was also determined that the canvas had likely been trimmed on the right side, altering the original composition.

Outcome of the Restoration

The restoration significantly improved the painting's appearance, bringing it closer to its original state as intended by Vermeer. The removal of the sky and the restoration of the dark background enhanced the painting's depth and the intimate atmosphere among the figures. This treatment also allowed for a reassessment of the painting's place within Vermeer's oeuvre, linking it more closely to his other early works through its composition and use of light.

Recent Findings

drawn from:
"Compositions in the Making Vermeer’s Changes," in Closer to Vermeer: New Research on the Painter and His Art, Anna Krekeler, Francesca Gabrieli, Annelies van Loon and Ige Verslype (2025).

A small adjustment to restore and reaffirm that focus can be seen in Diana's left sleeve, which was slightly extended over the red sleeve of the adjacent right nymph. The red colour of this nymph’s dress optically pushes forwards, Diana and her Nymphs, c. 1655–1656, indication of details a decorated quiver equipped with arrows lying on the rock to the left of Diana. This quiver with arrows shows striking similarities in design and pigment use to the one lying at Cupid's feet in the painting-within-a-painting in Vermeer’s Girl Reading a Letter at an Open Window from a few years later. This significant change illustrates that Vermeer originally chose a more traditional way of portraying Diana and her nymphs. By eventually reducing the attributes to only the crescent moon he redirected the viewer’s focus solely on the figures and their quiet interplay.^{Anna Krekeler, Francesca Gabrieli, Annelies van Loon and Ige Verslype, "Compositions in the Making Vermeer’s Changes," in Closer to Vermeer: New Research on the Painter and His Art, ed. Anna Krekeler, Francesca Gabrieli, Annelies van Loon, and Ige Verslype (Amsterdam: Rijksmuseum / Veurne: Hannibal Books, 2025), 59.}

Diana and her Nymphs hides another remarkable adjustment. The nymph in the background wearing a red hairband and looking down at the foot-washing initially had her head up, directed frontally towards the viewer. She might even have been looking directly at the viewer. This is reminiscent of depictions of Diana that were identified as possible precedents for Vermeer’s interpretation, such as the two paintings by Jacob van Loo: Diana and her Nymphs (1648, Berlin, SMPK, Gemäldegalerie) and (c. 1650, Braunschweig, Jacob van Loo, Diana and her Nymphs, 1648. Oil on canvas, 136.8 × 170.6 cm. Berlin, Staatliche Museen zu Berlin, Gemäldegalerie, inv. no. 765A) promising the illusion of Diana sitting in front. By slightly extending Diana’s sleeve, Vermeer seemingly attempted to reduce that effect to–again–ensure Diana is perceived as the main and central figure of the composition.^{Anna Krekeler, Francesca Gabrieli, Annelies van Loon and Ige Verslype, "Compositions in the Making Vermeer’s Changes," in Closer to Vermeer: New Research on the Painter and His Art, ed. Anna Krekeler, Francesca Gabrieli, Annelies van Loon, and Ige Verslype (Amsterdam: Rijksmuseum / Veurne: Hannibal Books, 2025), 58-60.}

The Procuress

Vermeer's The Procuress, painted in 1656, underwent a comprehensive restoration between 2002 and 2004 at the Gemäldegalerie Alte Meister in Dresden. The restorationwas lead by Marlies Giebe, the gallery's chief restorer. This effort sought to address the physical deterioration of the painting while uncovering elements of Vermeer's original technique that had been obscured over centuries.

The project benefited from extensive collaboration with external specialists and institutions. Experts from the Doerner Institute in Munich provided scientific analyses of Vermeer's materials and techniques, while colleagues from the National Galleries of Scotland and the Mauritshuis in The Hague shared documentation and insights. Additionally, conservation professionals from the Metropolitan Museum of Art in New York contributed their expertise. Art historians, including Albert Blankert and Annaliese Mayer-Meintschel, offered valuable perspectives on the painting's historical and artistic context. This interdisciplinary effort ensured a meticulous restoration, combining technical precision with scholarly rigor to honor the masterpiece's historical significance.

The restoration process also addressed structural issues, such as flaking and instability in the paint layers and canvas, ensuring the painting's longevity. Advanced imaging techniques, including X-radiography and infrared reflectography, were employed to uncover compositional adjustments made by Vermeer during the painting's creation. These analyses revealed deliberate repositioning of figures to achieve balance and harmony in the overall composition.

The cleaning process itself brought to light many details that had been obscured over time. Vibrant color contrasts reappeared, such as the interplay of textures in the woman's garments and the reflective surfaces of metallic objects. The luminous highlights on key elements of the painting further showcased Vermeer's attention to light and texture.

Throughout the restoration, conservators adhered to ethical guidelines emphasizing minimal intervention and the use of reversible materials. This ensured the historical integrity of the painting would be preserved for future conservation efforts.

Pigments

It was discovered that Vermeer employed a variety of pigments in The Procuress to achieve remarkable depth, contrast, and naturalism. The vibrant lead-tin yellow in the woman's jacket re-emerged after cleaning, showcasing the light primrose hue—rather than the murky yellow—as it appeared in Vermeer's time. Warm tones painted with red madder were revitalized, and the careful application of ultramarine blue—a pigment known for its expense and brilliance—was revealed in delicate details. Ultramarine was prominently used in the depiction of decorative pattern the wine jug, demonstrating Vermeer's deliberate choice of high-quality materials and exceptionally firm hand.

Carbon black and bone black were used to create deep shadows and strong contrasts, enhancing the chiaroscuro effects that give the painting its striking dimensionality. Lead white, a versatile pigment, was applied extensively for highlights and mixed with other colors to produce a range of luminous shades, adding body and brilliance to the composition. Earth pigments, such as yellow and red ochre, contributed to subtle tonal variations and the realistic rendering of skin tones and other elements. Lead white served as the base, providing luminosity and opacity, and was mixed with other pigments to create a range of light and mid-tones.

Red ochre was used to add warmth and subtle pinkish hues, contributing to the naturalistic rendering of the skin. Yellow ochre introduced golden undertones, helping to model the forms and add depth to the complexion. Carbon black was sparingly applied to create soft shadows and subtle contrasts, enhancing the three-dimensional effect of the figures. Vermilion, a bright red pigment, was used in small amounts to highlight features such as the lips or to accentuate rosy areas of the skin. These pigments were skillfully layered and blended, with glazes and fine transitions lending a softness and realism to the figures, showcasing Vermeer's mastery of color and texture in portraying human flesh.

Additionally, traces of verdigris or green earth were identified, likely employed for delicate shading and smooth tonal transitions, further demonstrating Vermeer's meticulous attention to color and form. In the shadows of drapery and textiles, these pigments were applied to create nuanced shading, particularly in the folds and darker areas of the fabrics. This careful application added depth and realism to the textures. In the figures' skin tones, traces of verdigris and green earth were blended into the base layers to introduce cooler undertones, balancing the warm hues of ochres and reds.

Evidence of glazing was identified in areas where Vermeer achieved subtle tonal transitions and depth, such as the deep shadows and drapery to create rich, translucent shadows and enhance the illusion of three-dimensionality.g

Varnish Rermoval

Prior to restoration, the painting showed significant signs of aging, with yellowed varnish and accumulated grime muting its vibrant colors and intricate details. Preliminary testing was first carried out to identify the chemical composition of the varnish and determine the most effective solvent mixture. This step was crucial to ensure that only the varnish was dissolved, leaving the underlying paint untouched.

Solvents were then applied in small, controlled areas using swabs, allowing the conservators to soften and lift the varnish incrementally. This cautious approach enabled constant monitoring of the painting's surface, ensuring that no damage occurred during the process. In areas where multiple layers of varnish had accumulated over time, the removal was performed layer by layer. This gradual method minimized the risk of exposing or harming the original paint, maintaining the integrity of Vermeer's work while restoring its original vibrancy.

Use of a Compass

Infrared reflectography and X-ray imaging of the painting revealed faint, underlying construction lines. The use of a compass would have allowed him to render geometrically accurate forms, ensuring harmony within the overall composition while demonstrating his technical skill. Circular lines in the paint of the jug was found inscribed into the paint layer to create the circular form of the wine jug, likely made using a pointed instrument, consistent with the technique of using a compass. These incisions provided guidelines for achieving the precise circular shape seen in the wine jug. Such findings align with Vermeer's reputation for meticulous planning and precision in his compositions.

Pentimenti

The restoration also revealed several pentimenti, or changes made by Vermeer during the painting process. For instance, X-ray and infrared imaging uncovered that the procurer's hand was originally placed closer to the transaction between the man and woman. Vermeer later painted over this detail, likely to shift the viewer's focus and create a subtler narrative. Additional adjustments were discovered in the clothing and lighting of the figures, indicating Vermeer's continuous refinement of the scene to enhance its overall balance and storytelling. X-ray and infrared imaging uncovered that the procurer's hand was originally placed closer to the transaction between the man and woman. Vermeer later painted over this detail, likely to shift the viewer's focus and create a subtler narrative. Additional adjustments were discovered in the clothing and lighting of the figures, indicating Vermeer's continuous refinement of the scene to enhance its overall balance and storytelling.

Infrared reflectography and X-ray imaging also revealed that Vermeer initially painted the young man without a hat and later added it during the painting process. This adjustment suggests that Vermeer refined his composition as he worked, potentially to emphasize the character's role in the scene or to balance the overall design. Such alterations are consistent with Vermeer's practice of making changes to achieve greater harmony and narrative focus in his works.

The restoration of The Procuress not only improved its physical condition but also provided a deeper understanding of Vermeer's techniques and artistic decisions. By integrating scientific analysis and ethical conservation practices, this project exemplified how modern restoration can bring historical artworks back to life while respecting their original intent. The revitalized brilliance of Vermeer's pigments and the rediscovery of compositional subtleties offer a renewed appreciation for this masterpiece within his body of work.

Girl Reading a Letter at an Open Window

The restoration of Vermeer's Girl Reading a Letter at an Open Window was a transformative process that revealed much about the painting's original composition as well as Vermeer's intentions. This restoration, completed in 2021, fundamentally altered the perception of one of Vermeer's most characteristic works.

Initial Research and Planning

The painting had undergone several previous restorations, with records dating back to 1838, when it was cleaned, mended, and varnished. Over time, these layers of varnish and overpainting aged, obscuring parts of the original work. By March 2017, a team of experts gathered in Dresden to assess the painting's condition and develop a plan for its restoration. This team included distinguished professionals such as Ursula Haller, Christoph Herm, Elke Oberthaler, Ige Verslype, Jørgen Wadum, Arthur K. Wheelock Jr., Marlies Giebe, Uta Neidhardt, and Christoph Schölzel. It was during this early phase that they began to suspect that the painting held more beneath its surface that could be recovered completely, with no risk.

Removing Yellowed Varnish

The restoration began with the removal of the yellowed varnish, which had been applied in 1838 and subsequently "regenerated"^{Varnish regeneration was an older conservation technique used to refresh the appearance of paintings without fully removing the aged varnish layer. Over time, varnish tends to yellow and become brittle, dulling the vibrancy of the underlying colors. To address this, conservators would soften the existing varnish using solvents like alcohol or turpentine, allowing it to re-coalesce and become more transparent. In some cases, heat was applied to make the varnish more pliable, aiding in its rebinding to the paint layer. After the regeneration process, a fresh layer of varnish was sometimes applied over the top to protect the now-refreshed original varnish and enhance the painting's gloss and color saturation. However, varnish regeneration had significant drawbacks. The process could be inconsistent, leading to uneven treatment where some areas of varnish were overly thinned or inadequately regenerated. The use of solvents and heat posed risks to the original paint layers, potentially causing damage. Despite these efforts, the varnish would often continue to yellow over time, requiring repeated treatments that could further compromise the painting. Additionally, the repeated regeneration and reapplication of varnish layers could result in a thick buildup on the painting's surface, obscuring fine details and altering the artist's intended effects.} several times over the following 170 years. Using cotton wool swabs soaked in organic solvent, restorers carefully removed this varnish, revealing Vermeer's original paintwork underneath. To their surprise, the original colors were found to be astonishingly fresh, indicating that the painting had survived largely undamaged over the centuries.

Understanding the Overpainting

As the varnish was removed, restorers noticed that certain areas, particularly on the left edge of the background, reacted differently to the solvents. This inconsistency suggested the presence of overpainting, presumably. Further scientific analysis, including the examination of paint samples, confirmed that the overpainting had been added much later and was not done by Vermeer himself. This discovery was crucial as it indicated that a significant part of the original composition had been altered after Vermeer's death, confuting the long-held hypothesis that it was the artists himself who had done the overpainting in order to hide a painting of a framed Cupid, which had been detected previously by x-radiography.

Reassessment and Decision

Throughout the restoration process, the team faced a critical decision: whether to preserve the painting in its overpainted state, which had become part of its historical narrative, or to remove the overpainting to restore Vermeer's original vision. After careful consideration, they decided to remove the overpainting. This decision was driven by a desire to experience the painting as Vermeer intended, rather than preserving the arbitrary changes made by a later hand.

Unveiling the Cupid

An X-ray taken of the painting in 1979 showed that there was a fully overpainted picture-within-a-picture of a nude Cupid that adorned the room's rear wall in the background. Annaliese Mayer-Meintschel first published this fascinating finding in 1982, and it has been cited in many works on the subject. Since then, academics have assumed that Vermeer rejected the Cupid painting as he was unhappy with the composition, and painted over the room's rear wall himself. New analyses in 2019 using advanced technology (X-ray fluorescence, infrared reflectography, and microscopic analysis determined the overpainting occurred decades after Vermeer's death. A layer of dust between the original paint and the overpaint indicated a significant time gap between the applications. Carefully, the restoration team began the delicate task of removing the overpaint, uncovering the Cupid in a state of remarkable preservation. The reveal of this figure was of fundamental importance, not just in terms of the painting's composition but also for understanding its narrative.

Christoph Schölzel, a painting conservator at Staatliche Kunstsammlungen Dresden, led the effort to remove a thick varnish layer hiding the Cupid image. Using a scalpel and microscope, he meticulously removed the overpainting layers to preserve the original paint underneath, at a rate of approximately one square centimeter per day.

Originally, the painting depicted a solemn girl reading a letter—thought to be characteristic of the manner of Rembrandt— but the addition of a Cupid painting behind her adds a more playful element to the narrative. This Cupid is similar to one in Vermeer's later work, Lady Standing at a Virginal and two other works, where in the case of the latter two appearance is less pronounced. This suggests that it might have been based on a painting of Cupid owned presumably by Vermeer's mother-in-law, Maria Thins. Restoration of the lower part of the painting also revealed the base of a wine glass or roemer,^{A roemer (Römer in German) is a type of drinking glass that originated in Germany during the 16th century and became popular throughout Europe, particularly in the Netherlands. It is characterized by its distinctive shape, with a wide, rounded bowl atop a thick, cylindrical stem often adorned with small, applied glass knobs or prunts for a better grip. The foot of the glass is typically broad and stable, making it ideal for use on uneven surfaces. Roemers were commonly used for drinking wine and are frequently depicted in still life paintings of the Dutch Golden Age, symbolizing wealth and the enjoyment of fine wine.} which was originally covered by Vermeer with a green curtain but left the base visible. This glass, painted in dark blue-gray with light highlights, was later overpainted along with the Cupid image.

Conclusion

After a multi-year investigation by a panel of international experts terminated in 2021, the results of the major restoration of Vermeer Girl Reading a Letter at an Open Window had significantly altered the painting's overall appearance, changing its atmosphere and meaning. The painting, created between 1657–1659, has been in the Gemäldegalerie's collection for over 275 years. The restoration of Girl Reading a Letter at an Open Window has allowed art historians and the public to appreciate the painting as Vermeer originally conceived it. The removal of the overpainting and varnish not only restored the balance and chromatic richness of the composition but also clarifies Vermeer's intended narrative. The recovery of Cupid underscores Vermeer's focus on love and emotional introspection.

The Milkmaid

drawn from:
"Compositions in the Making Vermeer’s Changes," in Closer to Vermeer: New Research on the Painter and His Art, Anna Krekeler, Francesca Gabrieli, Annelies van Loon and Ige Verslype (2025).

The Milkmaid for its stillness and the absolute focus on the maid's occupation. Conversely, Vermeer's path to arrive at this state of contemplation was not without diversion. Early in the development of the composition, Vermeer had placed a jug shelf on the rear wall behind the milkmaid's head and had a large woven basket, with a cloth on top, placed on the floor to the right of the figure. The 2022 research at the Rijksmuseum revealed that Vermeer must have discarded both items quickly, as they only appear as a sketch painted in black—with the basket additionally showing some underpainting—but were never laid-in further to be finished off in detail. The woven basket has been previously interpreted as a laundry basket. While laundry would typically consist of mostly white linens, the black underpainting Vermeer applied in preparation rather suggests a dark final colour, such as blue. Another possible interpretation is that of a fire basket. Equipped with wickerwork on top and featuring an earthenware basin with glowing coals, these baskets were used for heating and drying linens and swaddling clothes.^{Vermeer, who had eleven children, also had a fire basket in his home.} However, rather than hanging loosely over a woven superstructure, the fabric in the initial composition of The Milkmaid appears to be tucked in, as the basket's rim is entirely visible. Fabric being tucked in is reminiscent of that found on the backs of cradles. It is therefore also a possibility that Vermeer initially planned to include a cradle next to the milkmaid. The cradle would have been visible from the back, similar to the one depicted in Gerrit ter Borch’s Woman Sewing beside a Cradle (1656). By abandoning the jug shelf and basket and opting for an empty rear wall, Vermeer directed the viewer's attention solely to the maid and her task, minimizing distractions. Just like in Officer and Laughing Girl—less seems to be more.

The milkmaid's red skirt and blue apron also underwent a noteworthy and previously unknown alteration. The RIS-SWIR false-colour image^{RIS-SWIR false-color imaging (Reflectance Imaging Spectroscopy in the Short-Wave Infrared range) is a non-invasive technique used in the analysis of paintings to reveal compositional changes, underdrawings, and material differences not visible to the naked eye. By capturing reflected light beyond the visible spectrum and combining specific infrared wavelengths into a color-coded image, conservators can detect features such as hidden objects, alterations, or distinct pigments based on their spectral responses. In Vermeer’s Milkmaid, for example, this method exposed an earlier, broader version of the blue apron and suggested the presence of now-removed elements like a cradle or fire basket, offering valuable insight into the artist’s evolving intentions.} shows that initially, the blue apron was slightly broader and longer, with its lowest tip extending down to the lower edge of the painting. The red skirt underneath was only visible as a small red triangle pinched between the greenish-blue table cloth and the blue apron. By adjusting the composition to show more of the contrasting red skirt, Vermeer effectively enhanced the sense of depth in the foreground, creating a more dynamic visual balance.

^{Anna Krekeler, Francesca Gabrieli, Annelies van Loon and Ige Verslype, "Compositions in the Making Vermeer’s Changes," in Closer to Vermeer: New Research on the Painter and His Art, ed. Anna Krekeler, Francesca Gabrieli, Annelies van Loon, and Ige Verslype (Amsterdam: Rijksmuseum / Veurne: Hannibal Books, 2025), 68–69.}

View of Delft

The View of Delft is one of the most celebrated cityscapes in art history. Painted around c. 1660–1663, this work captures a view of Vermeer's hometown with remarkable precision and a striking sense of atmosphere. The painting underwent significant restoration in 1994, which revealed much about Vermeer's techniques and the painting's history.

Background of the Painting

View of Delft presents a calm, almost serene depiction of the city from the southeast, focusing on the harbor known as the Kolk. The scene is bathed in the soft light of a morning sun, with the Nieuwe Kerk's tower rising prominently in the background. Vermeer's meticulous attention to light, texture, and detail makes this work a prime example of his mastery in capturing the subtleties of his environment.

Provenance and Early Conservation

The painting was acquired by the Dutch State at an auction in Amsterdam in 1822. Before this, little is known about its history. Since its acquisition, View of Delft has undergone several treatments, including a lining in 1875 and the repair of a hole caused by a dislodged curtain rod in 1876.

1994 Restoration Process

The most comprehensive restoration occurred in 1994, when the painting was treated alongside Vermeer's Girl with a Pearl Earring. This restoration was carried out in a public setting, allowing visitors to observe the process.

1. Varnish Removal: The first step involved removing the old, yellowed varnish that had been applied during previous restorations. The varnish had darkened over time, obscuring the painting's brightness and clarity. This was a delicate process, particularly because the paint surface exhibited cupping—a condition where the paint forms tiny islands that can curl up and detach from the ground layer.
2. Handling Cupping: The irregular paint surface required careful handling during varnish removal. The cupping^{Cupping in painting refers to a condition where the paint layer becomes distorted, forming small, concave or convex deformations that resemble tiny "cups." This typically occurs when the paint layer loses its adhesion to the underlying surface, often due to environmental factors like fluctuations in humidity or temperature, aging, or the natural drying process of the paint. As the paint contracts or expands unevenly, it can lift from the surface, creating these cup-like shapes. Cupping is a significant concern in painting conservation, as it can lead to paint loss if not carefully stabilized and treated.} was most pronounced in areas containing lead white, particularly in the sky. Fortunately, despite the advanced cupping, the paint remained largely intact.
3. Retouching and Inpainting: After the varnish was removed, old retouchings were taken off as well, revealing slight abrasions in the paint layer. Notably, an earlier restorer had attempted to remove a figure Vermeer had painted but later decided to obscure. This figure was retouched out again, respecting Vermeer's final intention for the composition.
4. Repairing Damage: The restoration also addressed the hole in the sky caused by the falling curtain rod in 1876. The canvas patch used to repair the hole was still securely attached and did not require replacement. The hole and other minor losses were carefully filled and retouched to blend seamlessly with the surrounding original paint.
5. Final Varnishing: After retouching, a final varnish was applied to protect the paint surface and restore the painting's luminosity. This varnish was carefully chosen and included a UV light stabilizer to slow down future yellowing and aging.

Research and Discoveries

1. Painting Technique: Vermeer's technique in View of Delft is notable for its combination of thick, opaque impasto and thin, translucent paint layers. He used a varied palette to create the scene, employing bold, long brushstrokes in the sky and delicate highlights in the sunlit areas of the city.
2. Use of Ultramarine: Vermeer was known for his use of ultramarine, an expensive pigment derived from lapis lazuli. In View of Delft, ultramarine was used in the sky, the woman's apron in the foreground, and even in the foliage of the trees, demonstrating his mastery in creating rich, vibrant colors.
3. Optical Effects: Vermeer's interest in optical effects is evident in his depiction of light and reflection. The shimmering light on the hull of the boat and the reflection of the houses in the water are particularly striking examples of his skill in capturing the play of light on different surfaces.
4. Lead Soap Aggregates: One unexpected discovery during the restoration was the presence of lead soap aggregates in the red roofs of the cityscape. These aggregates, which give a gritty texture, were not originally part of Vermeer's technique but resulted from a chemical reaction over time between the oil and lead in the paint.

Outcome of the Restoration

The 1994 restoration significantly enhanced the painting's appearance, returning it to a state much closer to what Vermeer intended. The removal of the yellowed varnish restored the painting's brightness, making the scene appear almost as if viewed through a window into seventeenth-century Delft. The subtle play of light and shadow, the careful rendering of textures, and the overall composition once again became fully visible, reaffirming "View of Delft" as one of Vermeer's masterpieces.

This restoration not only preserved the physical integrity of the painting but also allowed for a deeper understanding of Vermeer's artistic process, contributing to the appreciation and study of his work.

Girl with a Pearl Earring

When the Girl with a Pearl Earring was purchased at auction by A.A. des Tombe^{A.A. des Tombe was a Dutch art collector known primarily for his role in rescuing and preserving Johannes Vermeer's painting Girl with a Pearl Earring, at a time when Vermeer's works were not widely recognized or highly valued. His full name was Arnoldus Andries des Tombe, and he lived from 1818 to 1902. In 1881, des Tombe bought Girl with a Pearl Earring at an auction in The Hague for a very modest sum—reportedly only two guilders with no other bids. At that time, Vermeer's works were not as famous or sought after as they are today.SInce he did not have any direct descendants, towards the end of his life, he decided to bequeath his art collection to the Mauritshuis in The Hague. Thanks to his generous donation, Girl with a Pearl Earring became part one of the museum's most famous and important pieces.} in 1881, its condition was described as being in "a sorry state of neglect." Before the painting entered the Mauritshuis collection in 1903, it was treated in Antwerp in 1881 by a restorer named Van de Haeghen (first name unknown). He lined the painting using a starch-based adhesive and probably consolidated the front of the painting with animal glue. In 1915, Derix de Wild "regenerated" the upper layer of varnish without affecting earlier retouchings, then he varnished the painting. De Wild performed another regeneration treatment in 1922. In 1960, Jan Cornelis Traas carried out a full restoration: he relined the support^{In painting restoration, "underlining" refers to the process of applying a protective layer of material, typically a fine fabric, to the back of a canvas to reinforce and stabilize it. This technique is often used when the original canvas has become weak or damaged over time, ensuring that it can support the paint layers without further deterioration. The underlining process helps preserve the structural integrity of the painting, preventing tears or distortions, and allowing the artwork to be safely handled, displayed, or further restored.} with a wax-resin adhesive, removed most old varnish layers, applied a new varnish, and retouched damages. Despite—and largely because of—these interventions, Girl with a Pearl Earring has survived in relatively stable condition.^{Abbie Vandivere, J. Wadum, K. J. van den Berg, et al., "From 'Vermeer Illuminated' to 'The Girl in the Spotlight': Approaches and Methodologies for the Scientific (Re-)Examination of Vermeer's Girl with a Pearl Earring," Heritage Science 7 (2019): 66, https://doi.org/10.1186/s40494-019-0307-5.}

Girl with a Pearl Earring was examined during a 1994 restoration treatment, within the project Vermeer Illuminated. Conservators and scientists investigated the material composition and condition of the painting using the analytical and scientific means that were available at the time: technical photography (visible light, ultraviolet fluorescence, and infrared), X-radiography, and stereomicroscopy. To understand the build-up of the paint layers, they investigated paint samples, often mounted as cross-sections.

Years later, in 2018, the Mauritshuis spearheaded a project The Girl in the Spotlight  involving a team of internationally recognised specialists working within the collaborative framework of the Netherlands Institute for Conservation+Art+Science+ (NICAS), with some scientists from other institutions. The painting was examined in front of museum visitors at the Mauritshuis. The imaging techniques employed were among the mostm advanced at the time, which included: technical photography, multispectral infrared reflectography, reflectance and fluorescence imaging spectroscopy (hyperspectral imaging), fibre optic reflectance spectroscopy, multiscale scanning optical coherence tomography, 3D scanning, 3D digital microscopy, macroscopic X-ray fluorescence and macroscopic X-ray powder diffraction. Furthermore, the samples mounted in 1994 were re-examined, and new forms of microscopic, organic and inorganic analysis were carried out to identify the pigments and binding media. Advances in computation and data science allow the results of these techniques to be co-registered and compared, and new results to be generated.^{Abbie Vandivere, J. Wadum, K. J. van den Berg, et al., "From 'Vermeer Illuminated' to 'The Girl in the Spotlight': Approaches and Methodologies for the Scientific (Re-)Examination of Vermeer's Girl with a Pearl Earring," Heritage Science 7 (2019): 66, https://doi.org/10.1186/s40494-019-0307-5.}

Woman in Blue Reading a Letter

The 2010-2011 Restoration^{Ige Verslype, "The Restoration of Woman in Blue Reading a Letter by Johannes Vermeer," Rijksmuseum Bulletin 60 (2012): 2-27.} It has been a long-standing wish to have Vermeer's Woman in Blue Reading a Letter restored. The highly oxidized, irregular and yellowed varnish, old discoloured retouching, overpaint and overfill along the bottom edge, as well as the numerous tiny paint losses, especially visible in the light coloured wall on the left and in the figure's blue jacket, interfered with the original cool blue hues, delicate details and overall legibility of the picture. To facilitate the restoration, an advisory committee was set up to provide insights into Vermeer's technique, conservation problems and art historical information.

After several tests, the varnish was removed with an organic solvent to ensure minimal mechanical contact with the fragile paint surface. The removal of the yellowed varnish revealed the intense blue hues and detailed paint surface. The shift in colour was quite dramatic, particularly in the shadowed area of the figure's blue jacket. While the blue of the chairs appeared to be the same as the blue of the jacket before the old varnish was removed, after its removal it became quite apparent that Vermeer had used two different shades. Once the varnish had been removed, it was also possible to remove the retouches and overpaints along the edges of the picture—exposing the bright orange filler material from a previous restoration—and some of the overpaints covering the damage at the bottom. Overpaint and overfill covering original paint along the large loss at the bottom, which could not be removed with solvents, were removed mechanically with a scalpel under the microscope.

At least six different filler materials could be discerned in and around the large damage, evidence of several previous restorations. Where it was not covering original paint, old inert filler was left and used as a base for retouching. With the removal of the old restorations in the lower right corner came a surprising discovery: small painted brass nails in the chair—delicate details painted by Vermeer that had been covered for decades—were revealed. It also became apparent that the area of the wall below the chair was originally a vibrant purplish blue, and that it had been painted over in the greenish-grey colour of the wall above the chair at a later date.

The removal of a thin brown overpaint covering the brown cloth laid over the table revealed the original rounded folds with slightly different hues. The four yellow dots of paint on top of the table and the small stroke of yellow paint above the letter extended over cracks in the paint layer, indicating that they were not original. They were easily removed with solvent and it became apparent that, with the exception of the third dot of yellow, which had been applied directly on top of the light blue tabletop, they had been covering dots of original white paint. The dots of yellow paint must have been added at some time to transform the small dots of original white paint into a string of pearls. Once the painting was cleaned, the old loss at the bottom was clearly visible, and it also became obvious to what extent the numerous tiny holes interfered with the legibility of the painting. These small holes needed to be concealed, and it was decided to do so with a gouache paint, as this material has a certain "body" that also acts as a filler. Because the holes were so small, this part of the inpainting was done under the microscope. The large loss at the bottom was filled and subsequently covered with gouache paint.

To imitate the structure of the original paint surface on top of the filler material, a silicone mould was made of the original paint surface elsewhere in the painting and pressed into an acrylic binder applied on top of the gouache base. Several seventeenth century Spanish chairs were studied, as was Vermeer's depiction of them in other paintings, in order to understand their construction. With this knowledge, and the fragments of original paint that were previously covered with overpaint, the chair leg in Woman in Blue Reading a Letter was reconstructed as Vermeer intended it, wide at the bottom and narrower at the top. Before the final inpainting was carried out, a stable synthetic varnish was brush applied to saturate the colours. The application of this varnish served to level out the uneven surface of the painting caused by the tiny holes and blisters to some extent. The final inpainting was done with a stable synthetic resin and loose pigments in order to achieve optimal concealment of the damage and restore the legibility of the image. A final natural varnish layer was then brushed on to the surface to fully saturate the colours, to seal off all retouches and to even out any differences in gloss.

Woman Holding a Balance

In 1994 conservators at the National Gallery cleaned the Woman Holding a Balance, removing discolored varnish from its surface. Their work revealed that at some point in the past, the painting had been extended by a half inch on all four sides. To restore it to its original size, conservators removed the added paint. Small losses are found in the figure, small areas of abrasion in the dark passages. Discolored retouching and old varnish were removed in 1994. Black overpaint covering the frame of the Last Judgment on the wall behind the woman has been removed, revealing two vertical bands of yellow paint along the right side of the frame. Overpaint that had been applied along the opened-out tacking margins when the painting was restretched on a larger stretcher has been removed. The painted image, now smaller, reflects Vermeer's original intention.

Recent technical studies at the National Gallery of Art revealed Vermeer's innovative use of materials during the underpainting stage. For example, in the tablecloth depicted in Woman Holding a Balance, an XRF copper map showed that Vermeer used a copper-containing pigment, likely verdigris, as a drier in the underpaint. This addition allowed the underpaint to dry faster, facilitating quicker progression to subsequent painting stages. The copper map also highlighted the vigorous, broad brushstrokes Vermeer used in the underpaint, which are not visible in the final image but played a crucial role in defining the light and shadows. Infrared reflectography reveals that Vermeer changed the position and increased the size of the balance and revealed slight traces of underdrawing and compositional changes that lie beneath a painting's surface.

Woman with a Pearl Necklace

Throughout these interventions, conservators adhered to principles of minimal intervention and reversibility, ensuring that any treatments could be undone if future conservation science deemed it necessary. Detailed documentation accompanied each restoration phase, providing a comprehensive record of the painting's condition and the methods employed.The essential composition we now see of the Woman with a Pearl Necklace was not Vermeer's original concept. Neutron autoradiography has revealed that the artist made critical changes in the composition. By extending the shape of the great folds of the slate-blue tablecloth in the still life, he eliminated a number of black and white floor tiles and more of the table's intricate structure. As a result, the viewer's attention is now drawn to the upper part of the composition. Another important modification was the exclusion of a musical instrument, most likely a cittern, which lay propped up diagonally on the foreground chair. Throughout these interventions, conservators adhered to principles of minimal intervention and reversibility, ensuring that any treatments could be undone if future conservation science deemed it necessary. Detailed documentation accompanied each restoration phase, providing a comprehensive record of the painting's condition and the methods employed.

However, the most startling alteration was the overpainting of a large wall map that subframed the standing girl. This map absorbed her presence and obfuscated the line of her gaze toward the mirror. The map was very likely the same one that appears in The Art of Painting.

According to Arthur K. Wheelock Jr., the "map, representing the physical world, and the musical instrument, referring to sensual love, would have given a context for interpreting the mirror and the pearls negatively rather than positively. Indeed, the sensual, earthy connotations are similar to those associated with Vrouw Wereld. The Vrouw Wereld (the Lady World) was a well-known allegorical figure dating back to medieval times who personifies worldly pleasures and transience." By removing the map and musical instrument, Wheelock proposes that Vermeer transformed the image into a poetic statement, evoking the ideals of purity and truth.^{Vrouw Wereld ("Lady World") is an allegorical figure common in medieval and early modern Dutch literature, art, and religious discourse. She represents worldly temptations, materialism, and the fleeting nature of earthly pleasures. Often portrayed as a beautiful woman adorned in fine clothing and jewels, Vrouw Wereld embodies wealth and sensual allure. However, her outward beauty typically conceals grotesque or decayed features, such as a skull hidden beneath her façade, symbolizing the emptiness and transience of worldly pursuits. Her imagery served as a moral warning, appearing frequently in sermons, plays, and moralistic texts. Vrouw Wereld’s attributes, such as luxurious garments, mirrors symbolizing vanity, and gold representing greed, underscored the dangers of succumbing to sin and placing excessive value on material wealth. Her figure is closely associated with the vanitas tradition in Dutch culture, which emphasized the transitory nature of life and the futility of earthly achievements in the face of death and divine judgment.}