Infrared reflectography: paintings, sculptures (all materials)
A camera detecting wavelengths of near infrared gives an image of the deep layers of the painting. Comparing this report with the visible work provides access to underdrawings or modified areas (restoration or pentimenti).
We shall notice that the characteristics of underdrawings, oftenly realised using graphite, make them particularly sensible to infrared reflectography. However, when drawn using sanguine (red pigment), they become invisible to the infrared.
Applied to other materials, such as plaster sculptures, this approach allows to highlight partially erased or covered inscriptions.
More generally speaking, it is an approach which reveal what could be hidden under layers of materials.
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