Technical Survey

Cross-section

Cross-section

Cross section blocks are often made of paint fragments to provide information on the layer structure of a painting as they can aid in the identification of pigments used in the paint-layer. A cross section is made by embedding a sample in resin, then cutting and polishing the embedded fragment to the layers of interest. Samples taken from The Marriage of Strongbow and Aoife indicate Maclise used prussian blue glazes over less expensive blue pigments such as smalt throughout the sky area.

Infra-red examination of the painting

Infrared Light

Infrared reflectography uses a heat-sensitive film for image capturing. When a painting is illuminated with infrared radiation it penetrates the surface and underlying layers. The absorption of infrared wavelengths varies for different pigments and the resultant image can help distinguish pigments that have been used in the painting or underdrawing. Infrared examination of the painting indicate Maclise stayed true to his original composition with only minor changes visible in the smaller details.

Ultra-violet analysis

Ultraviolet Light

Ultraviolet light waves are not visible to the human eye, however when a painting is exposed to these wavelengths they cause materials used by the artist to fluoresce in different colors. Aged varnish coatings often appear as a milky-green colour under UV light. Ultraviolet examination of The Marriage of Strongbow and Aoife is used before and during treatment to help indicate safe cleaning parameters whilst removing varnish from the surface of a painting.