The original support is a fine, tightly woven fabric. When the painting was lined, the format was enlarged about one-half inch on all sides by opening out and flattening the tacking margins. The composition was extended by overpainting these unpainted edges. Regularly spaced tacking holes and losses in the ground layer along the folds of fabric bent over the original stretcher confirm that these smaller dimensions were the original format.

A moderately thick, warm buff ground is present overall, and a reddish brown underpaint is found under the blue jacket.[1] Opaque, fluid paint of various densities is applied with fine brushstrokes, with the ground incorporated into the design in the woman's features and headcovering. Dense paint layers overlap with thin glazes to soften the contours. Some contours are softened by leaving a thin line of ground between two edges.

Thin, diffused glazes are overlaid with rounded, thick strokes to create specular highlights. No pentimenti are visible in the x-radiograph; infrared reflectography reveals a change in the position of the balance.

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.

[1] For pigment analysis of the paint layers see Kühn 1968, 191-192. Kühn's conclusion that the yellow of the curtain is Indian yellow is based on a sample taken from the overpaint near the edge of the painting. Subsequent pigment analysis of the ground was undertaken on 26 June 1974 by Robert L. Feller, Carnegie Mellon University, Pittsburgh, and by Melanie Gifford in June, 1994 (available in the Scientific Research department, NGA).