There are a number of studies on the application of each of the above mentioned imaging methods specifically for the identification of pigments: UV Fluorescence (UVF), UV Reflected (UVR), Infrared False Color (IRFC), Infrared Fluorescence and Infrared Reflectography. So the 8 imaging methods are called VIS (Visible), IR (Infrared), UVF (UV Fluorescence), UVF254 (UVC light source), UVR (UV Reflected), IRFC (Infrared False Color), IRF (IR Fluorescence), IRR (Infrared Reflectography), Figures 1 and 2. The acronyms for the MSI methods presented in this paper highlight first the spectral band followed by R (Reflected), F (Fluorescence), FC (False Color). This is an Open Access article distributed under the terms of the Creative Commons Attribution License (), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. © 2014 Cosentino licensee Chemistry Central Ltd. This paper illustrates a flowchart method for pigment identification based on the acquisition of MSI images in 4 spectral bands: Ultraviolet, UV (360-400 nm) Visible, Unlike other references, which suggest the use of software algorithms to analyze the MSI images, this paper proposes a more straightforward method simply based on visual examination and the use of a photo-editing software for the characterization of features apparent in the image. This method is more likely to succeed when applied on artworks where pigments have been applied in one single layer and not mixed as is the case with miniatures, drawings and prints. This simplified approach, though demonstrated to be limited in its analytical diagnostic capabilities, has the benefit of being accessible and easy to implement by professionals in the art conservation and examination field. In this way, selected pigments are likely to be identified by means of MSI examination. Will work for those which present peculiar behaviors in the range of the electromagnetic spectrum readily observable with an IR-VIS-UV modified digital camera (360-1100 nm) and an InGaAs camera (900-1700 nm). This method doesn't claim to allow the identification of all different pigments, but itĬorrespondence: Scholar at "CulturalHeritage Science Open Source" Blog,, Piazza Cantarella 11, Aci Sant'Antonio 95025, Italy The intention of this paper is to show that with a flowchart based methodology it is possible to tentatively identify some historical pigments by means of MSI performed with simplified equipment and without the aid of imaging analysis software. The use of MSI to tentatively identify pigments has an important advantage justifying its application: the rapid and low-cost survey of large areas. To identify pigments with an acceptable degree of certainty, at least one other material specific technique must be used to complement hyper or multispectral imaging diagnostics. Though, it is mandatory to point out that these methods are problematic and the user may be subjected to draw conclusions that remain uncertain, essentially, because pigments are often mixed and overlapped in layers to make the desired color and effect. Multispectral imaging (MSI) and Hyperspectral Imaging, have been suggested as methods for the non-destructive identification of 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 (320x256 pixels) rather than a more sophisticated InGaAs scanner system. 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 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. 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. 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. The literature on the application of Multispectral and Hyperspectral imaging for identification of pigments on artworks is sparse. Identification of pigments by multispectral imaging a flowchart method
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