Santi – Scanner for X-Radiography

Santi – Scanner for X-Radiography

CHSOS presents low-cost and practical methods to perform radiography on art and library items. We want to allow art professionals and small and medium studios and institutions to perform radiography with much easier equipment to handle. When it comes to Radiography it’s a question of costs but also and mostly, handling sensitive equipment, the X-ray radiation tube. 

Santi, the X-Radiography scanner is designed to match a low-cost dentist radiography system (X-tube and sensor) and deliver larger X-radiographs.  We do not sell the X-tube and the sensor but with Santi come instructions about compatible tube and sensor and where to find them.

The smaller, the better

There are different kinds of X-ray tubes. Small tubes or powerful ones. The bigger the tube to higher the cost. What really matters is the number of permits and limitations that are involved with handling and owning large tubes. So, our efforts are aimed at showing what we can do with the smallest tubes available on the market, those ones used by your dentist. Since these tubes have very low power, their regulation is much easier. So, it really makes sense to take out the best of them for art examination. 

Scanning

Dentists’ X-Radiography equipment is cheap and digital. We used that technology to build a low-cost and portable X-radiography scanner. 

Note: X-radiation is dangerous. Be sure to have all the necessary authorization in your Country to operate an X-ray tube. 

Testing the radio-opacity of pigments

More complete evaluation of the radio-opacity of the pigments was performed on a mini pigments checker. The pigments are in the same order as in the standard pigments checker but close to each other. So we could take the radiograph with fewer scans.
This test shows immediately the opacity that we can expect from different pigments. The more radio-opaque pigments (brighter in the radiograph) are those containing lead, such as lead white, lead-tin yellow, massicot, naples yellow, red lead. Less radio-opaque are pigments containing mercury such as vermilion. We can distinguish pigments containing copper, such as azurite, malachite, and verdigris Barely visible are the earth pigments, which contain light elements, iron, and manganese, as well those inorganic pigments containing other light elements, such as ultramarine. Organic pigments and lakes are, as expected, totally transparent.

Stitching

As an example of low-cost radiography scanning, we used the same panel made for this publication, A. Cosentino “Transmittance spectroscopy and transmitted multispectral imaging to map covered paints” Conservar Património 24, 37-45, 2016. Some historical pigments were painted over a canvas with a white preparation and then covered with a further titanium white paint layer. We scanned the left part of the panel with a matrix of 6 rows and 2 columns, for a total of 12 images, moving the scanner 2 cm on both the X and Y axis. The under paint made of radio-opaque elements become visible, such as cobalt violet (Co), red lead (Pb) and vermilion (Hg). On the other hand, yellow ochre (Fe), titanium white (Ti) and lamp black (C) contain light elements and become transparent in the radiograph.

Training program on Radiography

These methods are discussed in our Training program. Practical activities are included in the programs delivered in our Studio in Italy where we have our authorized facilities for running the X-ray equipment.
In the training programs delivered abroad, we will not provide practical activities for X-radiography, but we will discuss the methods with plenty of the usual practical and technical information.