Digital radiography is one of the physical inspection techniques used in the field of cultural heritage. The
technical features of the system used for digital radiography of paintings we investigated is described in the section titled
Linear scanner for NDT . The samples have been provided by the
"Opificio delle Pietre Dure" Institute in Florence. One of them was a benchmark panel with a number of classified original
pigments. The panel was a 72×57 cm2 canvas mounted on a wooden frame about 7 cm large, 2.3 cm thick (see figure left).
The maximum field of view of our detector was 13×18 cm2, thus a complete radiography of the panel was possible only as a mosaic
of several radiographies. A photograph of the panel is reported in the figure below where the scheme of the mosaic of
radiographies is shown. The various radiographies were partially superimposed to be sure to cover all the surface of
the panel. The reconstructed mosaic of radiographies that formed the complete radiography of the panel is shown in
Figures below. In figures is shown also a detail zoomed of the entire image.
Figures: reconstructed radiographic mosaic of the benchmark panel of picture (top) and a single radiography of the mosaic
(bottom). The radiographies were made at 25 kVp, 0.6 mA, 400 ms, single frame. The woof of the canvas is clearly resolved by
the system. The different absorption of x-rays by the various pigments is visible as well as the pigment distribution.
Details of the wooden frame and nails are visible too.
