6.4 Former Vermeers
Through the years, there have been many paintings with questionable origin put forth as by Vermeer, some have been accepted as genuine Vermeers for a time, but later rejected. As noted in the introductory chapter, such attribution judgments need to be holistic in combining relevant insights gained through connoisseurship and scientific image analysis.1 This section examines what weave maps can tell and what they cannot with regard to attribution.
Among the paintings attributed to Vermeer are several canvases that do not exhibit striped weave density pattern matches with any other canvases of paintings by Vermeer listed in table 1 in § 6.1.2 Thus, the absence of a weave match by a painting under examination with a painting attributed to Vermeer is not a mark for or against attribution of the painting under examination. The presence of a weave match is just one feature among many that would be used in an attribution declaration. For example, knowledge of studio practice would be helpful in deciding if the match could be to a painting by a different artist who shared studio space and materials with Vermeer.
As an illustration of the application of weave maps in a rollmate hunt, we will examine the X-radiographs of four paintings previously considered as by Vermeer. The average horizontal and vertical thread counts and the tight count matches among the paintings by Vermeer (L01-L23 and L26-L36) are listed in table 1.
The scatter plot of the average thread counts for these four former Vermeers along with the 34 paintings by Vermeer on canvas in figure  helps to visualize the tight count matches noted in table 1.
As table 1 and figure 1 show, Lady with a Guitar (38, Philadelphia Museum of Art) has tight matches with three of Vermeer's canvases: Mistress and Maid (L21), Young Woman Seated at a Virginal (L34) and The Guitar Player (L35). Were Lady with a Guitar (38) to have a weave match with any of these, it would provide important evidence in the attribution of the painting. However, visual analysis of the weave maps reveals no plausible matches, and so the similarity of the average thread counts must be considered a coincidence.
Average Thread Counts and Count Matches of Former Vermeers.
Scatter Plot of Average Thread Counts for L01-L23, L26-L36, and the four former Vermeers as 38-41 marked in red.
As known fakes, the paintings by Van Meegeren are not expected to be rollmates with any of the other paintings. However, Woman Playing the Cittern (40) and Interior with Man and Woman at the Harpsichord (41) have the same set of tight count matches with Vermeer paintings: The Procuress (L03), The Letter Reader (L05), A Lady Writing (L20), and Allegory of the Catholic Faith (L32). Visual comparison of the weave maps of The Procuress (L03), The Letter Reader (L05), A Lady Writing (L20), and Allegory of the Catholic Faith (L32) with the weave maps in figures  and  does not reveal any weave matches.
Weave Maps of Lady with a Guitar (38) (from 0.5 cm evaluation squares centered on 0.25 cm grid).
Weave Maps of Van Meegeren / Woman Playing the Cittern (from 0.5 cm evaluation squares centered on 0.25 cm grid).
Weave Maps of Van Meegeren / Interior with Man and Woman at the Harpsichord / NK3255 (from 0.5 cm evaluation squares centered on 0.25 cm grid).
The important points here are:
- Without matching average thread counts, canvases cannot be rollmates.
- A close average thread count match, while common among pairs of paintings by Vermeer, is not a reliable indicator of rollmates.
- A weave match, along with Vermeer’s presumed lack of pupils, between an accepted Vermeer and a painting of similar style is strongly indicative of an attribution to Vermeer.
- A lack of a weave match by a painting of similar style to any of the accepted Vermeers offers no positive or negative information regarding attribution of the painting of similar style.
1 A.K. Wheelock Jr., ‘The Scientific Examination of Works of Art: Its Potentials and Its Limitations’, in: C.R. Johnson Jr. (ed.), Counting Vermeer: Using Weave Maps to Study Vermeer's Canvases, RKD Studies, The Hague (RKD) 2017, chapter 1 (https://countingvermeer.rkdstudies.nl/1-the-scientific-examination-of-works-of-art-its-potentials-and-its-limitations).
2 In: W. Liedtke, Vermeer. The Complete Paintings, Antwerp 2008, and therefore appearing in table 1 in § 6.1 of this publication.