Undermåling

Undermåling is a term used in painting and art conservation to describe a layer of paint applied beneath the visible, final layer. This layer is not intended to be seen directly but serves a functional purpose in the overall composition and preservation of the artwork. Undermåling can be made of various pigments and binders, often differing from the materials used in the upper layers.

The purpose of undermåling can be multifaceted. It might be used to establish a tonal base, to block in large areas of color, or to prepare the surface for subsequent glaze layers. In some historical painting techniques, undermåling played a crucial role in building up the illusion of depth and form. For example, a dark undermåling might be used to create deep shadows, while a lighter one could serve as a foundation for luminous highlights.

Additionally, undermåling can contribute to the longevity of a painting. It can act as a barrier between the canvas or panel and the upper paint layers, helping to prevent cracking or delamination. The choice of pigments in the undermåling can also influence the overall color and luminosity of the final image, as the colors of the upper layers interact with those beneath.

The study and analysis of undermåling are important aspects of art conservation and art historical research. Techniques such as X-radiography, infrared reflectography, and cross-section analysis allow conservators and scholars to examine these hidden layers without damaging the artwork. This information can reveal details about the artist's working process, original intentions, and any alterations made during the creation of the piece. Understanding undermåling helps in authenticating artworks and in developing appropriate conservation strategies.