Multispectral imaging - Ultraviolet False Color (UVFC)
Analytical technique description:
With the introduction of digital photography this technique has become a post processed technique. It could be used for identification of pigments and materials.
The importance of this technique is the opportunity to obtain an image hold information both visible and ultraviolet range, the last one invisible to naked eyes. So pigments look the same in visible region but with different chemical composition, can be differentiate by their different behaviour in ultraviolet.
Applications:
Pigments on every surface such as fresco, canvas, marble and wood.
Basics:
Ultraviolet is superimposed on visible image. In visible image RGB channels are shifted, replace green channel with blue and red channel with green. The blue channel is replaced with ultraviolet image. In this manner a false colours image is obtained.
Instrumental details:
Canon EOS 400D,  graphics editing program (Florence Unit).
ICVBC - AREA DI RICERCA CNR DI FIRENZE
Via Madonna del Piano, 10 - 50019 Sesto Fiorentino (FI)
Tel. 055 5225484 - Fax 055 5225483
Institute for the Conservation and Valorization of Cultural Heritage