Technological investigations represent one important aspect of the conservator’s work. They help to arrive at a well-founded understanding of an artwork and serve as an important reference for assessing such matters as its authenticity, dating, attribution and changes in condition, as well as for developing a conservation strategy. When the results are documented and published, colleagues elsewhere who are confronted with similar problems can look to them for comparison. The chief focus is on questions such as: What materials did the painter employ? How did the working process evolve? Did the artist revise his painting before he arrived at its final state?
The examinations at the Städel Museum were carried out according to a pre-established plan. The latter called for the employment of optical and radio-diagnostic (non-destructive) methods: in-depth examination under varying light conditions (incident light, transmitted light, reflected light, raking light) and ultraviolet radiation, and examination of the surface with the stereo microscope. An infrared camera and a digital X-ray device were moreover used to produce images of all of the paintings examined.
Further information on the procedures is found in the exhibition catalogue.