A paper on Multispectral Imaging has been published on Heritage Science, “Identification of pigments by multispectral imaging a flowchart method” 2:8, 2014.
In this paper I provide a flowchart method to use the multispectral imaging to tentatively identify pigments. I have been posting extensively on this idea for a while on the “Cultural Heritage Science Open Source” blog and this paper summarized all that thoughts, tests and trials. This post introduces also an online searchable database which collect the same data in the paper. It adds the possibility to search the 56 pigments based on their MSI (MultiSpectral Imaging) properties.
From the Abstract: “The literature on the application of Multispectral and Hyperspectral imaging for identification of pigments on artworks is sparse. While these methods do not provide the analytical capability that spectroscopies do offer, the use of spectral imaging has the advantage of being a rapid and relatively low-cost solution for the examination of
large areas. This paper presents a flowchart for the identification of historical pigments applied with gum Arabic using multispectral imaging (wavelength ranging from 360 to 1700 nm) performed with a modified digital camera for infrared, visible and ultraviolet photography; and an InGaAs camera for infrared reflectography. The flowchart method will be most successful on paint made of one layer of pure pigment, and it can selectively discriminate only a fraction of the 56 pigments analyzed. Though, considerably limited in its analytical capabilities, the low cost
and speed of the workflow make the method worthwhile, even if only to localize retouching and areas appearing the same hue but painted with different pigments. The InGaAs camera is the only expensive instrument used in this study but its cost is relatively affordable for the average painting conservation studio since only a model with a low
pixel count is required (320×256 pixels) rather than a more sophisticated InGaAs scanner system.”
This paper presents the “Pigments checker“. I make it with Kremer pigments and the overall idea is to have a standard test panel to be used to test different equipment (Imaging and Analytical). I do provide it or the mini pigment checker (selection of 18 historical pigments) as a gift, respectively, for institutions or professionals that require my training program on multispectral imaging.
Pigments Checker is for photographers, conservators and scientists interested in technical documentation of paintingss. It has 54 swatches of historical pigments designed for infrared photography, ultraviolet photography and other technical photographic methods for art examination. Check it out!
Pigments Checker is a collection of 54 swatches of historical pigments that have been applied using gum arabic as a binder on a cellulose and cotton watercolor paper, acids and lignin free. This paper is not treated with optical brighteners, it’s slightly UV fluorescent, and it reflects IR. Two cross-hair lines, 0,2 mm (vertical) and 0.4 mm (horizontal) are printed on each swatch of paper before the application of paint, in order to have a means to evaluate the pigments’ transparency in the IR and IRR imaging. Among all the pigments and their varieties ever used in art these pigments collection select the most used ones from antiquity to early 1950’.