Archeomatica International 2019

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Fig. 3 - Antonello da Messina, Annunciata: a) IR Reflectography (2015); b) details of the face and theveil; c) detail in IR False Colour (2006).vantage of the materials available, typical during the 15 thcentury palette. This gave volumes, tones and chiaroscurothrough mixtures and glazes, calibrating thickness and typologyof the stroke; increasing thick-looking texture of thesurface fabric, or very thin layers for the flesh tones andthe highlights. These surveys also showed a variety types ofunderdrawings found in the many work of arts (Poldi & Villa2006a; Poldi & Villa 2006b; Villa 2006; Benizzoni et al. 2007;Poldi 2009).Subsequently, a decade on, the new diagnostic study in thispaper, was carried out in 2015 directly in situ, in the Sala diAntonello of Palazzo Abatellis, by using XRF-IRR INTRAVEDOscanner. The study provided new elements specifically fora correct interpretation of the variations and alterationsof shadows and lights in the veil over the time and of thepainting area between the face of the Virgin and the blueveil. This pictorial surface, altered in the past by cleaninginterventions, was not studied in depth during the previousscientific investigations as documented in 2007 by FrancoFazzio in his technical condition report (Fazzio 2007). In thecase of the paintings analyses, the combined equipmentfor performing IR Reflectography and XRF investigation becomesparticularly interesting because the X-ray fluorescenceresults complete the information from the diagnosticIR imaging. In fact, IRR highlights aspects no longer noticeablein the visible range or hidden by superficial layers, andthe XRF mapping contextually returned the elemental compositionof the overlapped pictorial layers, supporting theunderstanding of the pictorial stratigraphy and the distinguishingof any integration areas.MATERIALS AND METHODSThe previous and the new investigations of the Annunciatahas always been carried out in situ, in the Sala di Antonelloat the Galleria della Sicilia di Palazzo Abatellis, with portableinstrumentation, by keeping the panel in its showcasein the closing day of the museum (Fig. 2).The previous False The previous False ColourInfrared investigations (Cacciatoreet al. 2007; Prestileo& Bruno 2007; Prestileo et al.2009) were performed by usinga Digital CCD Artist camera(with 23 mm F/1.4 lens and objectivefrom 18-108 mm F/2.5)by Art Innovation. The imagesacquisitions were made usingthe CPS100 manual positioningsystem, as sources of lighting,of two 50W halogen lamps (forshooting in the visible and infraredup to 1150 nm).The new investigation was carriedout by using INTRAVEDOscanner, an ultra-high-resolutionIR and XRF scanner (andpositioning system Scanner XY:useful size 1.8×1.8 m, SW forpositioning with 0.1 mm stepreproducibility), to acquire insitu XRF mapping, for analysingthe chemical compositionof the pictorial layers characterizedby different spectralresponse in the IR range.Indeed, in order to utilise anXRF mapping acquisition system,a XY scanner was optimized and integrated, from botha software and hardware point of view.The equipment is composed by a motorized XY scanner,constituted with a modular and light structure, to provideIR digital Reflectography through an InGaAs sensor. Startingfrom this instrumental apparatus, the scanner was integratedwith an automatic positioner system, capable of supportinga maximum weight of 5 kg. This allows the housingof other equipment for not-destructive imaging and spectroscopicinvestigations. Among the various opportunities,a system for X-Ray fluorescence analysis coupled with theautomatic positioner scanner provide several advantages.They guarantee a set-up of constant measurement and controlledgeometry, aimed at creating False Colour maps forthe determination of the spatial and stratigraphic distributionof the individual chemical elements revealed.The XRF portable instrument consists of a miniature X-raytube system. This includes the X-ray tube (max voltage of40 kV, max current of 0.2 mA, target Rh, collimator 1 or 2mm), the power supply, the control electronics and the USBcommunication for remote control; a Silicon Drift Detector(SDD) with a 125 to 140 eV FWHM @ 5.9 keV Mn Kα line EnergyResolution (depends on peaking time and temperature);1 keV to 40 keV Detection range of energy; max rate ofcounts to 5.6 × 10 5 cps; software for acquiring and processingthe XRF spectra. Primary beam and detector axis forman angle of 0 and 40 degrees respectively directly pointingtowards the sample surface. Measurement parameters wereas follows: tube voltage 35 kV; current 80 μA, acquisitiontime 60 sec for single shot and 20 sec for each spectrumacquired for lines scanning; no filter was applied betweenthe X-Ray tube and the sample; the distance between sampleand detector was 1 cm. The setup parameters were selectedto ensure a good spectral signal and to optimise thesignal to noise ratio (SNR).20 ArcheomaticA International Special Issue
Cultural heritage Technologies 21RESULTS AND DISCUSSIONThe Infrared Reflectography obtainedby the InGaAs sensor at 1700nm confirmed the executive detailsshown by previous IR acquisition(Poldi & Villa 2006a; Poldi & Villa2006b; Cacciatore et al 2007; Prestileo& Bruno 2007; Prestileo et al.2009), highlighting higher resolutionto reveal several changes made byAntonello and the pictorial areas toprevious restoration treatments. Inparticular, the size of the thumb ofthe right hand has been changed bythe artist three times, the little fingerof the same hand was more bentcompared to the first draft. Besides,the middle finger of the left handwas slightly inclined compared tothe first draft in which it appearedrelaxed and, therefore, longer.Moreover, in the Virgin’s face, theunderdrawing traces revealed theareas of shade (area to the left ofthe nose and under the chin) anddetails of the hair. The flicker holesof the xylophagous insects, stuccoesand pictorial integrations due to1942 restoration (Brandi 1942; ArchivioRestauri ISCR 13 th March 1942;Archivio Restauri ISCR 14 th March1942) have been highlighted (Fig. 3).Previous investigations in InfraredFalse Colour already suggested aspectral difference between the innerportion of the veil along the leftcheek of the Virgin (Fig. 3) characterizedby a different tone than theentire veil that reveals the typicalred spectral response of lapis lazuliblue pigment. This is not distinguishablein visible image (Cacciatore etal. 2007; Prestileo & Bruno 2007;Prestileo et al. 2009).The different spectral response inthe area between the face and theveil confirms the need to understandif this surface is affected by thethinning of the original blue layer, orinstead, due to a possible undocumentedpictorial integration real-Fig. 4 - Antonello da Messina, Annunciata: localization on photographic image of XRF singlespot measurements carried out to identify the pigments used on the different layers ofcolour and selected marker element for the XRF mapping analysis.ID area Colour Si Ka S Ka K Ka Sn La Ca Ka Fe Ka Cu Ka Hg La Pb La Sr KaA1 Dark Red ND 1847 1150 ND 3147 4698 1577 1200 30544 527A2 Light Blu 460 1519 1761 ND 3953 1575 619 ND 11823 1201A3 Black ND 1575 950 ND 19581 813 8485 ND 851 1505A4 Red ND ND 378 ND 1073 1491 510 1265 32605 629A5 Dark Red ND 2060 1793 ND 18125 980 772 ND 1019 1890A6 Brown ND ND 880 1455 6717 4282 439 ND 16004 1429A7 Brown ND ND 773 1444 2351 1075 556 ND 32789 718A8 Flesh tone ND ND 539 ND 3687 7712 510 895 19391 1360A9 White ND ND 344 ND 1366 1098 406 ND 30811 NDA10 Dark blue 270 1331 1394 ND 3931 1166 523 ND 13067 879Tab. 1 - Chemicalelements detectedby XRF single spotmeasurements. Theintensity values,expressed in totalcounts, refer to Kαor Lα peaks of eachelement; “ND” (NotDetected) refers tothe absence or thepresence below thedetection limits forthat element.
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Page 4 and 5: SUMMARYDOCUMENTATION6 QGIS, pyarchi
Page 6 and 7: DOCUMENTATIONQGIS, pyarchinit and b
Page 8 and 9: the digital survey information take
Page 10 and 11: Fig. 10 - Example of 3D Model (dens
Page 12 and 13: Fig. 12 - Example of Qgis Grid for
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Page 18 and 19: RESTORATIONIRR and XRF investigatio
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Page 24 and 25: DOCUMENTATIONHazards, heritage prot
Page 26 and 27: Budget restrictions, lack of traine
Page 28 and 29: RESTORATIONThe Crucifix Chapel of A
Page 30 and 31: MSI photos produced using the panor
Page 32 and 33: Because the pigment tends to oxidiz
Page 34 and 35: Bibliography[1] S. Galli, G. Barone
Page 36 and 37: INTERVIEWSave the Syrian Heritage:t
Page 38 and 39: Fig. 5 - 3D Model of the Citadel of
Page 40 and 41: GUEST PAPERVIRTUAL ARCHAEOLOGICAL E
Page 42 and 43: THE DENOUMENTExisting models of ext
Page 44 and 45: COMPANIES AND PRODUCTSNEW TRIMBLE R
Page 46 and 47: AGORÀFig. 1 - © AFN archives. Aug
Page 48 and 49: EVENTS11 - 13 JUNE 202012th Europea
Page 50: Paestum Salerno19-22 novembre 2020P

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