Proceedings e report - Firenze University Press

EFFECT OF THERMAL TREATMENT ON STRUCTURAL DEFECTS OF MODEL PANEL PAINTINGS
the authors of the NG have not come across any published scientific work focused on artificially aged
wooden samples that imitate old artistic substrates.
(a) (b)
Fig. 1. (a) An artificially-made sample (Sample 1-Group 1); (b) Schematic cross-section of the sample.
The protocol followed at the first stage of thermal treatment of the model panel paintings is presented
in table 1. The procedure was performed in a thermal chamber (Memmert Company).
The samples were examined by the technical partners by means of Digital Speckle Holographic
Interferometry (IESL), Shearography (ITO) and Dynamic Holographic Interferometry (CSL). At a
second stage, some of the samples were further treated whereas others were restored and then treated
again.
The preliminary results that are presented in this paper have been aroused from the samples’
examination performed by the co-authors of CSL, by means of DyHI [3]. Two standard setups have
been used, i.e. 2 front illuminations or 1 back and 1 front illumination with 175IR lamps.
Table 1: The protocol followed at the first stage of the thermal treatment of the samples
Group Sample Thermal protocol
1 All Continuous heating at 102 o C for 480 hrs
2 All Heating at intervals at 102 o C for totally 66,5 hrs
1 (IESL) Continuous heating at 102 o 3
C for 17,5 hrs
2 (CSL) Continuous heating at 102 o C for 46hrs
3 (ITO) Continuous heating at 102 o C for 141 hrs
4 All Continuous heating at 85 o C for 247 hrs
5 All 1. Continuous heating at 60 o C for 66,5 hrs
2. Continuous heating at 90 o C for 148 hrs
6 All Same as GROUP 2
3. Results
Some representative results of the numerous experiments that have been performed by CSL are
presented in Fig. 2 – Fig. 6. The presented inteferograms have been processed so that sheared images
and diagrams are acquired. Nevertheless, only some examples that may substantiate the effect of
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