Assessment of real aging in selection process of replacement materials for stone monuments conservation.
Submitted: 2016-01-20
|Accepted: 2016-01-20
|Published: 2011-04-15
Downloads
Keywords:
Compatibility, Stone, Calibration, Colour, Cultural heritage
Supporting agencies:
Abstract:
Reconstruction of monuments often raises the question of stones replacement. It must be aesthetically durable, which means the stone must age like the original one. This study presents an image processing chain, from capture to visualisation, to compare stones at different states of aging: recently extracted from quarry, weathered on old buildings, and cleaned on monuments recently restored. This tool includes: (1) a digital still camera calibration, (2) a chromatic adaptation transform and (3) a resizing process. To test it, a case study was conducted to assess the compatibility of three types of limestone. This graphical tool helps the selection of replacement materials by visual comparison between several possible stones in order to select them by aging properties and visual resemblance.
References:
BRILL, Michael H., "The relation between the color of the illuminant and the color of the illuminated object". Color Research & Application. (1995) 20: 70– 5. doi:10.1002/col.5080200112.)
CHORRO E., PERALES E., de Fez D., LUQUE M. J., and MARTÍNEZ-VERDÚ F. M., “Application of the S-CIELAB color model to processed and calibrated images with a colorimetric dithering method,” Optics Express 15, no. 12 (Juin 11, 2007): 7810-7817. http://dx.doi.org/10.1364/OE.15.007810
FAIRCHILD M.D., “A Revision of CIECAM97s for Practical Applications ”, dans Color Research & Applications, Wiley Interscience, vol. 25, no 4, August 2000, p. 260–266
ICOMOS-ISCS, Illustrated glossary on stone deterioration patterns, 2008
THORNBUSH. M.J. and VILES, H.A., “Photo-based decay mapping of replaced stone blocks on the boundary wall of Worcester College, Oxford”. Building stone decay: from diagnosis to conservation. In, Prikryl, R. and Smith, B.J. (eds.) (2007) Geological Society Special Publication, 271: 69-75.P. https://doi.org/10.1144/GSL.SP.2007.271.01.08
THORNBUSH. M.J., “Grayscale calibration of outdoor photographic surveys of historical Stone Walls in Oxford, England,” Color Research & Application 33, no. 1 (2, 2008): 61-67. https://doi.org/10.1002/col.20374
STOKES M. (Hewlett-Packard), ANDERSON M. (Microsoft), CHANDRASEKAR S. (Microsoft), MOTTA R. (Hewlett-Packard) Version 1.10, November 5, 1996 “A Standard Default Color Space for the Internet: sRGB” ICC, [online] http://www.color.org/sRGB.xalter [Consulta: 22-04-2010].
