T e c h n i c a l a r T i c l e Complementary Quantitative Approach to Unsolved Issues in Art History Similarity of Visual Features in the Paintings of Vermeer and His Probable Mentors M I n S e o K im a n d J e o U n g H o o n K im Who is the most probable mentor to Johannes Vermeer? To provide to uncover the mentor to Johannes Jan Vermeer (1632–1675). complementary evidence for this question, the authors quantitatively The identity of Vermeer’s mentor and the nature of his train- analyzed and compared the visual features of the works of Vermeer ing remain a mystery owing to lack of evidence [9–12]. Thus, with those of artists proposed as his possible mentors. The results ABSTRACT to reveal this mentor of Vermeer, we created and compared a showed that Vermeer and Gerard ter Borch have similar artistic styles in many respects. scientific reservoir of the artist’s signature elements. UnCovering the MenToR To vermeeR Artwork contains many features that the unaided eye cannot The identity of Vermeer’s mentor has attracted a fair amount easily detect. For this reason, works of art are difficult to ana- of critical attention. At present, five artists have been pro- lyze manually in a quantitative fashion owing to the complex- posed as Vermeer’s mentor in light of archival documents ity of their contents [1]. Conventional artwork analysis relies [13–15]. The first is Carel Fabritius (1622–1654), recognized heavily on either historical evidence or highly subjective ap- as Rembrandt’s most gifted pupil. A poem by Arnold Bon praisal, and has many limitations [2]. Those who study art (1634–1691) indicates that Vermeer succeeded Fabritius as have thus turned to scientific methods, such as X-ray imag- the foremost painter in Delft [16]. This hypothesis is sup- ing, infrared photography and pigment analysis, to address ported by the similarity of the two artists in terms of subjects an increasing number of problems in art history. Neverthe- and style and by their common interest in perspective and less, these methods also have inherent limitations related to optics. As Vermeer owned three paintings by Fabritius, this their risk of irreparable damage to artworks. Moreover, the assumption is reasonable. However, this hypothesis conflicts results obtained by microanalyses of paint samples cannot be with the dates of Fabritius’s residence in Delft and Vermeer’s straightforwardly generalized [3]. Accordingly, artwork anal- age at that time. The second candidate is Leonaert Bramer ysis stands in great need of noninvasive analysis and objective (1596–1674), another successful Delft artist. The principal methodology to support traditional approaches. Meanwhile, reason for proposing him as Vermeer’s mentor is the subtle biologically motivated image processing has been developed connection between Bramer’s blue and Vermeer’s. Vermeer as a complementary approach for the analysis, evaluation and used a distinctive blue hue, and its similarity with Bramer’s identification of artworks, including associating a specific is regarded as vital evidence. Moreover, Bramer’s drawings painting with a painter, classifying a painting by its school of paintings in the collection of Vermeer’s father testify to a of art, authenticating paintings and finding influential links long association with the Vermeer family. Similarly, Abra- between painters [4–8]. Hence, the present study combined ham Bloemaert (1566–1651), the third candidate, was a dis- traditional art appraisal with biologically motivated image tant relative of Vermeer’s mother-in-law and trained many processing techniques as an attempt to standardize artwork pupils in Utrecht [17]. Vermeer might have trained in Am- analysis. As the first step in realizing this concept, we sought sterdam or Utrecht after spending the first four years of his apprenticeship in Delft [18,19]. This finding supports the likelihood of Vermeer studying under Bloemaert. A fourth Minseo Kim (artist), Graduate School of Culture Technology, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, candidate is Gerard ter Borch (1617–1681), who is believed Republic of Korea. Email: [email protected]. to have influenced Vermeer. The compositional concept and Jeounghoon Kim (artist), School of Humanities & Social Sciences, Korea Advanced Institute of Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, chosen subject matter of the two artists show striking re- Republic of Korea. Email: [email protected]. semblances, especially in picturing the secluded privacy of See www.mitpressjournals.org/toc/leon/52/2 for supplemental files associated a person reading or writing a letter. In addition, ter Borch with this issue. and Vermeer cosigned a document two days after Vermeer’s 164 LEONARDO, Vol. 52, No. 2, pp. 164–174, 2019 doi:10.1162/LEON_a_01401 ©2019 ISAST Downloaded from http://www.mitpressjournals.org/doi/pdf/10.1162/leon_a_01401 by guest on 30 September 2021 wedding [20]. In view of these facts, it is quite likely that Image DataseT Vermeer was familiar with works by ter Borch, as they might We created an image dataset from various websites offering have been intimate acquaintances. Finally, Rembrandt van documentary records of ownership provided by art muse- Rijn (1606–1669) is also a possible mentor. Vermeer would ums. This process helped minimize the source dependency have felt the impact of Rembrandt, especially his powerful of the images as well as verify that those analyzed were based chiaroscuro and sfumato effects. Vermeer almost certainly on the actual visual content [24]. Second, this study did not studied Rembrandt’s style indirectly [21,22]. Fabritius was a consider painting genre, given the focus on the superficial pupil of Rembrandt and worked in the latter’s studio; as such, components of the painting style of each artist observed their artistic styles in terms of subject, setting and composi- in all their paintings, such as the way of drawing lines (e.g. tion are similar in many cases. Thus, the advisability of this width and orientation), constructing shapes (e.g. drawing study’s method will be validated if the stylistic similarities of face contours) and choosing colors. In a preanalysis step, this two painters can be extracted. study found that the genre does not strongly determine an artist’s idiosyncratic style related to drawing lines or faces and Artistic STyleS of vermeeR choosing color. Third, this study classified the artists into two Art historians examine the following factors when visually groups in terms of the number of paintings they produced. assessing Vermeer’s styles. First, sfumato is a drawing style One group comprised Vermeer and Fabritius, who were not without lines or borders, in the manner of depicting smoke prolific artists; we included all their available paintings. The or a plane beyond the focus. Vermeer used blurry lines be- artists in the other group were those who produced many cause he regarded shadow as more significant than elabo- works: Bramer, Bloemaert, Rembrandt and ter Borch. We rated lines for separating different objects. Second, pointillé sorted their paintings based on representative paintings; is a light expression technique in which an artist forms then, we included only paintings that were contemporary points on a polished or metallic surface. Vermeer added with the works of Vermeer. Subsequently, the image dataset new interpretations to the typical pointillé method by us- contained 535 images from six different painters, as shown ing the technique particularly on subjects with unreflecting in Table 1. surfaces, including bread, cloth and baskets. Third, Vermeer Fourth, we collected 266 face images from the entire image used complementary colors to emphasize the effects of light dataset and used them for the radial frequency analysis. As and enhance the vividness of the quality of the materials. In- not all paintings had face images, the analysis depended on deed, Vermeer is known for his pairings of yellow ocher and the number of face images available. We gave special note to cobalt blue. Fourth, Vermeer’s faces in his artworks mean the position of the nose, which influences the formation of to depict mental activities. Many of his paintings portray the face contour. Meanwhile, the range of head orientations women as leitmotif in a domestic context. Apart from these provides reliable discrimination at around 20 degrees [25]. characteristics, light and perspective are among the major Thus, we selected only face images in which the nose did not technical innovations of Vermeer, who is well known for deviate from the face contour. Fifth, for the color analysis, we rendering the effects of light [23]. Meanwhile, his style pro- extracted a total of 1,489 cobalt blue values and 1,177 yellow duced geometrical spaces that evoke a feeling of glimpsing ocher values from the paintings. However, as a number of through a keyhole. The current study deals with three fac- the paintings do not include cobalt blue or yellow ocher, we tors—line, face and color—in the comparative analysis of analyzed each artist with the average value. Sixth, we normal- Vermeer and his possible mentor as regards their common ized each painting to 256 × 256 pixels without changing the artistic styles. aspect ratio. To fit the ratio of each painting, we cropped the TABle 1. number of images of artworks by Vermeer and the five candidate mentors in the dataset used in three analyses. vermeer Bramer Bloemaert fabritius Rembrandt ter Borch Total Orientation 33 108 139 33 131 91 535 Analysis Radial Frequency 28 31 44 23 82 58 266 Analysis Cobalt Blue 435 228 213 58 159 396 1,489 Color Values Analysis Yellow Ocher 152 238 165 47 294 281 1,177 Values Kim and Kim, Complementary Quantitative Approach to Unsolved Issues in Art History 165 Downloaded from http://www.mitpressjournals.org/doi/pdf/10.1162/leon_a_01401 by guest on 30 September 2021 background parts when such parts were not important to the Renaissance painter Pietro Perugino (1450–1523) and neo- overall composition.