Macro investigation
In the macro examination , the paint layer of a painting is examined in a magnification range of approx. 2: 1 to approx. 25: 1 with the help of a magnifying glass or a stereo microscope. The documentation and evaluation of a macro examination takes place with the help of macro photos. Therefore, this article also includes the field of painting photography in the near and macro range.
Application area
The macro examination is one of the methods of painting examination , which are summarized under the generic term painting surface examination . The most important areas of work in which this method is used are the style-critical investigation ( style criticism ), the investigation of the painting technique , the investigation of lettering and signatures , the investigation of craquelé as well as the conservation-restoration investigation.
Historical overview
Towards the end of the 19th century, art history began to include the painting detail and the technical structure of a painting in its research. We know little about the process of these first investigations. However, it can be assumed that they were made with a magnifying glass. The microscope was only systematically used to examine paintings in the early years of the 20th century.
Arthur Pillans Laurie, an English chemist, is considered a pioneer in this field of research. He developed the so-called “traveling microscope” for the macro investigation, a microscope that was attached to a tripod in front of or above the painting. His systematic research focused on brushwork, that is, on artistic handwriting. In 1930 Laurie reported on the results of his research with the help of macro photos at the International Museum Conference in Rome, which was under the auspices of the League of Nations. A resolution recognized the importance of macroinvestigation as an aid to attribution issues. In 1932 he published a comprehensive work on the brushwork of Rembrandt and his school.
technology
Today, in addition to the various magnifying glasses, the stereo microscope is mainly used for macro studies. The stereomicroscope was developed by Zeiss at the turn of the 19th and 20th centuries. It became an indispensable tool for painting. All examinations for which the human eye needs a magnification can be carried out more easily with this device. They can be performed on the standing, hanging or lying work of art. There are special stands for the examination. Combined use is made possible by the modern operating stands, to which a stereomicroscope with phototube can be attached in a self-supporting manner and pivoted into all positions.
Close-up and macro photography of paintings
Macro photography is carried out after the macro examination with the digital camera on the stereo microscope in order to document the knowledge gained for further evaluation. This is also possible with a camera specially equipped for this purpose (intermediate rings, bellows, macro lenses). Despite the first early work towards the end of the 19th century, painting photography in the close-up and macro-range only gains in art history and in restoration studios with the advent of panchromatic films with their higher sensitivity and the ability to reproduce the colors of a painting in graduated gray values Meaning. In 1937 the possibilities for enlargement were limited. It was not until the twenties and thirties that macro photos were found more frequently in specialist art literature, probably for these reasons and for printing reasons.
The advantages of this technology can be seen when studying older publications. Giovanni Morelli , an Italian art historian, developed a new method for identifying paintings in 1890. He still had to fix his comparative examples and details in drawings for publication. Even Theodor von Frimmel published in his first published in 1894 "painting Customer" only individual much "hard" to and in detail some meaningful photos. Moreau-Vautier in 1912 and later Laurie published the first good macro shots that could be used for style criticism. Laurie in particular is groundbreaking for the style-critical macro investigation with his extensive work on the painting style of Rembrandt and his school (see above).
Illumination
The illumination for the macro examination and the macro photography is done with spotlights, possibly also projectors, which shine a bundled “sharp” light onto the painting. They emphasize the surface structure more strongly and, as a rule, also allow shapes in very dark color areas to be interpreted.
literature
- Knut Nicolaus: paintings. Explore-Discover-Explore . Braunschweig 1979
Individual evidence
- ^ AP Laurie: The pigments and the mediums of the old masters . London 1914.
- ↑ AP Laurie: The brushwork of Rembrandt at his school . London 1932.
- ^ M. von Rohr: Treatise on the history of the stereoscope . 1908.
- ^ D. Rosen, H. Marceau: A study in the use of photographs in the identification of paintings . In: Technical Studies in the Field of Fine Arts . tape 6 , 1937, pp. 17-40 .
- ^ I. Lermolieff: The Galleries Borghese and Doria Pamfili in Rome . 1890.
- ^ Theodor von Frimmel: Handbook of painting studies . Leipzig 1894.
- ^ Ch. Moreau-Vautier: The Technique of Painting . London 1912.
- ↑ Knut Nicolaus: Painting. Explore-Discover-Explore . Klinckhardt & Biermann, Braunschweig 1979.