The historical paint analysis is a scientific analysis of architectural completion, including not only paint but also metallic finishes and clear and clear finishes used in historic buildings. The main purpose of the analysis is to determine the final color used at a certain time in the history of the building, usually its original construction, but not always. Secondary objectives include the determination of materials such as media (water, oil, latex, etc.) and pigments (organic pigments, inorganic pigments, dyes, etc.). The paint analysis is also used in time as a dating technique for various building elements.
Typical problems encountered in historical paint analysis include things like paint loss, surface damage, new materials, substrates, delamination, media and pigment damage, and crocodiles.
Video Historic paint analysis
Histori
The analysis of historic architectural pain found its roots in the early 20th century in the United States. The historic preservation movement began in 1849 with the preservation of Mount Vernon, the home of George Washington. The early preservationists began to realize that the enduring paint and finishing are very important but may not be the original, or historic, finish. Interest in historic wallpapers is also developed with an interest in paint and historic colors. One of the earliest attempts came with the restoration of Williamsburg, Virginia funded by John D. Rockefeller in the 1920s. A preliminary investigation by a simple scratch from the final result by Susan Nash from the original living building produced a palette that became popularly known as the color of Williamsburg.
In the 1950s and 1960s serious efforts in investigating the color of the original paint were underway at Independence National Historical Park in Philadelphia by architect Penelope Hartshorne Batcheler. The pioneering effort was introduced, for the first time in the country, the use of stereo microscopes to more thoroughly examine the 18th century paint in Independence Hall. Batcheler also introduced the use of the Munsell Color System for matching and referenceing the original paint color. Its major publication, "Paint Color Research and Restoration", is the first publication on the analysis of historic architectural paints for original color determination. At the same time, in the UK, microscopy of paint samples was developed by Joyce Plesters of the National Gallery, London who works primarily with paintings of horses but also with samples from frescoes.
In the 1960s and early 1970s, Morgan W. Phillips at the Society for the Preservation New England Antiquities (SPNEA) was involved with historic paint and color analysis, especially at Harrison Gray Otis House in Boston. At the same time, E. Blaine Cliver, Historical Architect, who originally worked with Batcheler at the National Park Service (NPS) in Philadelphia, then with the National Trust for Historic Preservation in Washington, DC and later at the Northeast Regional Office of NPS, became involved with historic paint analysis, especially in the laboratory at Building 28 of the former Boston Navy. In the early 1970s, Frank S. Welsh joined NPS in Philadelphia and began research and studies on historic paints with Penelope Batcheler, where he introduced the use of the National Bureau of Standards Color Name Charts (NIST) for naming suitable colors to the System Color Munsell. Welsh was also the first to introduce the term "paint analysis" into a historic preservation lexicon. As an independent historic color paint consultant, one of his first major projects is Monticello, home of Thomas Jefferson. In the mid-1970s, Matthew J. Mosca began working for the National Trust with Blaine Cliver. Later, as a conservation consultant, Mosca examined Mount Vernon's historic color.
Advances in paint science research by these people suggest that popular Williamsburg colors have been matched by fading and aging. During the 1980s and 1990s Colonial Williamsburg consulted with Welsh to conduct comprehensive paint and color analyzes on many buildings in historic areas. In his research, "the first modern scientific paint analysis" there, asserted that the Williamsburg color palette does not represent the true historical color. In addition, he found that in many cases, their early attempts had incorrectly matched the layers of paint later, some nineteenth century.
Historically, the paint analysis done on the site carefully removed the paint layer then to reveal the finished sequence down to the substrate. This is the methodology used during the initial recovery completed at Historic Williamsburg. Although this method is used by some practitioners, it is not uncommon because of the inherent problems of misinterpretation and failure to overcome problems such as aging paints and discoloration. Since the analysis is completed under laboratory conditions, samples are collected in the field for later analysis and may be collected by the analyst or by his clients who then send them to him.
Maps Historic paint analysis
Laboratory analysis
The main purpose of the analysis is to determine the historical settlement and to determine the principal components such as media or basic pigments. There are two methodologies in the preparation of paint samples for microscopic analysis. The first, derived from the medical world, is treating the sample as a specimen and arranging it to a fixed position in a permanent medium such as paraffin. The specimen is then pounded flat, giving a horizontal surface for viewing under a microscope. The second is to let the sample in a loose condition with a damaged surface which can then be manipulated under a microscope to allow multiple layers views. The main drawback of the first method is that the grinding process tends to obscure layers, especially the same or identical color layer. It also provides only one fixed point of view. The second method lacks this deficiency, although the skills and experience are required to effectively manipulate the sample.
After sample preparation, they are usually viewed under an optical microscope using natural northern light or artificial light polarized to simulate natural northern light. Northern light is essential to make accurate colors without the effect of yellow sunlight direct spectrum. Each individual layer is identified and, usually, matched with the Munsell color system. The Munsell color system is a scientific system in which color has been spanned into a color fan based on three attributes: color or color, chroma or color saturation, and neutral or darkness or light values. Unlike the color system developed by paint manufacturers, the Munsell system provides an unchanging reference standard that is unaffected by the market and changes color appetite.
Color notation, color, showing a sample relation with a scale of 100 times the same color visually. There are 10 main colors, five staples and five medium in this scale. Color is identified by initials indicating the group's central members: red R, yellow-red yellow, yellow yellow, yellow-green yellow, green G, blue-green BG, blue B, purple-blue PB, purple P, and red-purple PR. The colors in each group are identified by the numbers 1 through 10. The most purplish of red, 1 on a scale of 100, is set as 1R, the yellowest as 10R, and the middle hue as 5R. Color 10R can also be expressed as 10, 5Y as 25, and so on if notation of hue as number is desired. Chroma shows the departure rate of a certain hue from the neutral gray axis of the same value. This is the color saturation force of neutral gray, written/0 to/14 or further for maximum color saturation.
The value, or lightness, forms a neutral-colored gray axis of the color wheel, starting from the black, the number 1, to the white at the top of the axis, the number 10. The visual value can be approached with the help of a neutral gray chip from the Rock or Soil Color chart with ten intervals. The color parameters can be expressed with numbers semi-quantitatively as: hue, value/chroma (H, V/C). The "medium red" color should serve as an example for presentations with three color attributes, 5R 5.5/6. This means that 5R is located in the middle of the red hue, 5.5 is the brightness of Munsell value near the center between light and dark, and 6 is the degree of chroma Munsell, or color saturation, which is at the center of the saturation scale.
References
Source
- Batcheler, Penelope Hartshorne. "Cat Color Research and Restoration", Technical Leaflet # 15, American Association for State and Local History, Historical News , Vol. 23, No. 10, (October 1968)
- Baty, Patrick. The RÃÆ'Â'le of Paint Analysis in Historic Interiors. The Journal of Architectural Conservation. (March 1995): 27-37.
- Baty, Patrick. Scrape or Not Scratch? Traditional Paint News, Vol 1 No. 2 (October 1996): 9-15.
- Baty, Patrick. "The Benefit of Hindsight". Some Tips on Commissioning Paint Analysis An article based on a paper given at the English Heritage Layers of Understanding conference taking place in London on April 28, 2000.
- Bristow, Ian C., Architectural Colors in English Interior, 1615-1840 , Yale (1996)
- Bristow, Ian C., Color and Home Interior Painting Technology, 1615-1840 , Yale (1996)
- Gettens, Rutherford J., and Stout, George L. Painting Materials: Short Encyclopedia . New York: Publication of Dover, (1966)
- Hughes, Helen, ed., Layer of Understanding: Seminar Continues 28 April 2000 , Donhead (2002)
- Maycock, Susa and Zimmerman, Sarah Exterior Historical Drawing: Colors, Applications, and Rules: Resource Guide , Cambridge History Commission, Cambridge, Massachusetts, (1998/2006)
- Moss, Roger W. American Paint: Historical Building Colors Preservation Press, Washington, D.C., (1994)
- Moss, Roger W. Century of Color: Exterior Decorations for American Buildings, 1829-1920 , American Life Foundation, Watkins Glen, New York, (1981)
- Phillips, Morgan W. "Problems in the Recovery and Preservation of Old House Paint, Preservation and Conservation", in the Principles and Practices. Proceedings of the North American Regional Regional Conference, Williamsburg, Virginia, and Philadelphia, Pennsylvania, 10-16 September. 1972 . The Preservation Press, National Trust for Historic Preservation in the United States, (1976)
- Sherwin-Williams. Inheritance: Authentic Exterior Color of American Buildings, 1820-1920 American Life Foundation, Watkins Glen, New York, (1981)
External links
- http://www.apti.org Association for Conservation, International
- Crick Smith/Lincoln University's paint analysis report for Sheldonian Theater, Oxford.
- http://mcri.org/home/McCrone Research Institute.
- http://www.mccroneatlas.com The McCrone Atlas of Microscopic Particle
- http://www.modernmicroscopy.com Modern Microscopy (Online Journal)
- Oestreicher, Lisa, 'Decorative Archeology', Building Conservation Directory , (2001)
- Oestreicher, Lisa, 'Seeing the colors of the past', Building a Conservation Directory , (2006); Lisa Oestreicher in England.
- Traditional Cat Forum, historic research group based in the UK
Source of the article : Wikipedia
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