Large-scale investigation of plaster detachments in historical murals by acoustic stimulation and video-holographic detection
Gerd Guelker|Klaus D. Hinsch|Holger Joost
In the conservation of historical murals an important issue is detection plaster or paint layers that detach from supporting material and thus threaten to fall off. Commonly, walls are inspected by acoustic response a gentle finger-tapping (percussion method). Since this costly cumbersome technique there need for metrological instrument serving same purpose. last few years we have shown, time-average version electronic speckle pattern interferometry (ESPI) with increased sensitivity in combination excitation object can be powerful tool monitoring loose areas. It offers full-field, video real time capability has advantage non-contact remote operation which, example, extremely useful large buildings. Recently, fully computer-based evaluation control system was added assist introduction method as generally approved artwork monitoring. Principles instrumental features equipment presented some results their interpretation obtained computerized church chapel at St. John's convent Mnstair, Switzerland demonstrated.
Proceedings of SPIE