TOWARD A NEW VIEWPOINT FOR THE ARTIST

Communication between the artist and the scientific and technological community has been so tenuous during the past 50 years that the artist is not using knowledge and techniques which originate in that world. Conversely, the scientists and technicians have little insight into the problems of artists, making it difficult for the artist to obtain information he knows he needs. Some of the concepts and techniques valuable to artists are outlined in this paper with a special emphasis on those relating to color. Artists' pigments and vehicles are rapidly changing. Channels of information are needed to keep him current and knowledgable. The artist must use both additive and subtractive color simultaneously, since the visual world he utilizes in creating a picture consists largely of additive situations, but the mixture of his paints is a subtractive process. Metamerism is a problem for the artist as it is in color matching for industry. Color systems, although long known, have never been adequately utilized. The Munsell system is the most practical one at the present time for several reasons. Expanding the Munsell notation to include a relative intensity dimension for pigments would add to its usefulness. A color slide rule and a table of approximate chroma loss between pairs of additive colors are proposed to aid the artist in creating depth effects, illumination effects and transparency effects. The artist should be practical in obtaining and using the facts of paint technology, but flexible in the application of systematic color in order to keep his options open. The use of color systems and techniques, while of value to every artist, can be used at many levels for differing purposes. Such concepts must be tailored to the individual artist's needs.     

Digitally reconstructing Van Gogh's Field with Irises near Arles part 3: Determining the original colors

In earlier articles, we determined the spatial distributions and concentrations of all pigments used by Van Gogh in his painting Field with Irises near Arles. The colors of some pigments are expected to have changed over time, especially those of chrome yellow, cochineal, and eosin lake. For all pigments in this painting, we made physical paint reconstructions by following historical sources on raw materials and production processes, and we determined their optical properties. We combined this with pigment concentration maps to reconstruct the original colors of the painting digitally. When substituting the reconstruction paints into the calculations, we found that technical‐scientific data was not sufficient to resolve several issues. In those cases, discussions within the broad interdisciplinary team allowed us to make informed decisions. These issues refer to the representation of the sky area, and the original contributions of the red lake pigments to local colors. The digitally reconstructed colors of the painting show that due to discoloring of red lake pigments, the irises in the field have changed from a warm purple to purplish blue, and many pink spots in the field have turned to white. The range of yellows in the field has decreased and partly turned to dark brown. The digital reconstruction gives a better understanding of the color scheme used by Van Gogh when compared to remarks the artist made in letters when describing this painting. Also, the original color composition is seen to be aligned with color theories on which Van Gogh based his work.     

Theoretical analysis of subtractive color mixture characteristics

Understanding the characteristics of the stimulus values of colors obtained by subtractive color mixture is not easy, compared with those obtained by additive color mixture, since the relationship between superimposed absorption media and the stimulus values is not simple. In this article, using the assumption of the Lambert‐Beer model for subtractive color mixture, we prove several theorems regarding the stimulus values of colors obtained by subtractive color mixture. Although these theorems are proved theoretically, numerical illustrations are also shown to confirm the theorems. The results of this paper will contribute to a systematization of subtractive color mixture. © 2003 Wiley Periodicals, Inc. Col Res Appl, 28, 175–181, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.10143     

Printing the light

This paper explores the relationship between additive and subtractive mixing for colour printing. Using Spectraval mica pigments (Merck)—marketed as RGB pigments—colour is generated by selective reflection and prints are based on additive colour mixing principles, that when printed onto black paper, create white and a range of colours. Although currently used mostly for decorative effects, they can be the basis of additive 'process' inks, that present new opportunities for and challenges to traditional print markets. The viewing angle dependency of their selective reflection favours applications in security printing similar to the holograms on bank cards for example. Traditional measurement and modelling methods are difficult to apply due to the layering and irregular dispersion of pigments.     

Examples of interference and the color pigment mixtures green with red and red with green

In industrial paint formulations, interference pigments are usually mixed with color pigments. Transparent interference pigments mix together according to the laws of additive mixing and color pigments to the laws of subtractive mixing. The behavior of both types differs depending on whether similar colors such as pearl green and green or contrasting colors such as pearl green and red are mixed. In this article examples of these differences for color measurement are discussed, along with showing the resulting charts. © 2001 Wiley Periodicals, Inc. Col Res Appl, 27, 276–281, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.10063     

Theoretical analysis of subtractive color mixture characteristics V—Centroid of subtractive tristimulus values

In additive color mixture, when more than two component tristimulus values are given then the mixture result is determined from a linear combination of the components. On the other hand, in subtractive color mixture, the resultant tristimulus values are not uniquely determined from component tristimulus values. Hence, analyses regarding the minimum and the maximum bounds are very important to understand the possible ranges of tristimulus values of subtractive color mixture. In our previous series of articles, several theorems have been proven related to the bounds. In addition to the values, the centroid of a possible range is very important and essential to the prediction of subtractive color mixture. In the present article, several theorems related to the centroid are provided and proven. © 2006 Wiley Periodicals, Inc. Col Res Appl, 31, 418–424, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20247     

浅谈新彩人物画的形神表现

新彩是有别于古、粉彩的新的彩绘形式,具有发色稳定、颜色品种多、附着力强以及彩绘技法多样,艺术表现力强等工艺特色。画好新彩人物,不仅需要扎实的绘画技巧,而且需要全面的艺术修养。     

介绍几种Gyricon电子纸

电子纸是近年来引起广泛关注的平面显示技术 ,本文从双色球结构、荷电性、用途等角度 ,介绍了加色法、减色法、高亮度彩色以及准四色彩色和双稳态Gyricon电子纸 ,描述了Gyricon电子纸的控制电路 ,认为提高显示反差和亮度是电子纸产业化的关键。     

Let's Say Goodbye to the Color Circle*

A rhombohedral representation of the color solid is described, giving equal prominence to the additive and subtractive basic (primary) colors and to black and white.     

简述王恩怀陶瓷艺术的传承与创新

陶瓷艺术家、中国工艺美术大师王恩怀出身陶瓷世家,自小随其父人称"青花大王"的王步学艺作画,又拜著名陶瓷美术家、"珠山八友"之一的刘雨岑为师学习粉彩,笔者尝试从传承、创新以及传承与创新二者相融合三个方面,从青花、粉彩、青花斗彩三类陶瓷装饰技法,简述其陶瓷艺术风格的演变和成熟。     

Characterization of spray paints used in street art graffiti by a non‐destructive multi‐analytical approach

Often associated with acts of vandalism, graffiti can also be identified with the so‐called street art movement. Moreover, in the historical context of visual arts from the 20th and 21st century, graffiti spray paints feature among the materials employed in the work of representative artists such as Lucio Fontana, Richard Hamilton, Yves Klein, or David Alfaro Siqueiros. In this study, a large number of artist spray paints were analyzed by means of X‐Ray Fluorescence (XRF), Fourier Transform Infrared Spectroscopy (FTIR), spectrophotometry, and Hyperspectral Imaging (HSI). The aim of the study was to provide a chemical characterization of the main organic and inorganic components present within the spray paint formulations by means of a complementary non‐destructive approach. Titanium white, zinc white, bismuth vanadate yellow, ultramarine, strontium sulfide, iron, and copper oxides, along a series of pigments of the azo, phthalocyanine, and quinacridone classes could be identified. High amounts of barium sulfate as well as calcium‐based extenders were also detected. FTIR analysis provided important information regarding the binder composition, mainly modified alkyd resins being identified. Additional information related to the existing chromophores as well as specific binder‐pigments interactions could also be highlighted within the HSI data sets. Overall results provide new insights on the complex chemistry of this new range of materials, which could help future investigations carried on street art graffiti, contemporary murals, or mixed‐media artworks.     

Production of white pigments based on zirconates and titanates using the precipitation method

Experimental data on the synthesis of zirconates and titanates of s and d elements of group II by the precipitation method are summarized. It is established that a chemical reaction takes place between the components under alkaline precipitation. Subsequent thermal treatment of the obtained precipitate makes it possible to synthesize materials with a perovskite-like structure, which are recommended as white pigments for producing paints suitable for decorating glass and enamel articles. __________ Translated from Steklo i Keramika, No. 2, pp. 22–24, February, 2006.     

Whiter than white: options for the compounder

A number of white pigments can be employed in plastic compounds to achieve strong white colours and high reflectance, as well as for modifying other colours and increasing brightness. Titanium dioxide is the most important of these pigments for the plastics industry, but there are some alternatives as well. Plastics Additives & Compounding summarizes some of the issues at stake for compounders when selecting a suitable white pigmentation system.     

Complementary colors theory of color vision: Physiology,color mixture,color constancy and color perception

I describe complementary colors' physiology and functional roles in color vision, in a three‐stage theory (receptor, opponent color, and complementary color stages). 40 specific roles include the complementary structuring of: S and L cones, opponent single cells, cardinal directions, hue cycle structure, hue constancy, trichromatic color mixture, additive/subtractive primaries, two unique hues, color mixture space, uniform hue difference, lightness‐, saturation‐, and wavelength/hue‐discrimination, spectral sensitivity, chromatic adaptation, metamerism, chromatic induction, Helson‐Judd effect, colored shadows, color rendering, warm‐cool colors, brilliance, color harmony, Aristotle's flight of colors, white‐black responsivity, Helmholtz‐Kohlrausch effect, rainbows/halos/glories, dichromatism, spectral‐sharpening, and trimodality of functions (RGB peaks, CMY troughs whose complementarism adapts functions to illuminant). The 40 specific roles fall into 3 general roles: color mixture, color constancy, and color perception. Complementarism evidently structures much of the visual process. Its physiology is evident in complementarism of cones, and opponent single cells in retina, LGN, and cortex. Genetics show our first cones were S and L, which are complementary in daylight D65, giving a standard white to aid chromatic adaptation. M cone later split from L to oppose the nonspectral (red and purple) hues mixed from S+L. Response curves and wavelength peaks of cones L, S, and (S+L), M, closely resemble, and lead to, those of opponent‐color chromatic responses y, b, and r, g, a bimodal system whose summation gives spectral‐sharpened trimodal complementarism (RGB peaks, CMY troughs). Spectral sharpening demands a post‐receptoral, post‐opponent‐colors location, hence a third stage. © 2011 Wiley Periodicals, Inc. Col Res Appl, 2011     

Color Properties of Liquid Crystals and Their Application to Visual Arts*

Selective reflection properties of cholesteric liquid crystals are reviewed. It is then shown that the color of superimposed coatings of these substances is perceived as that of an additive mixture of colors of the coatings. This property permits one to synthesize many spectral reflectance distributions. A greater color gamut than is possible with other colorants can be realized. Applications to visual arts that take advantage of the additive color properties, the highly saturated colors, and the dependence of colors on temperature, angle of illumination, and angle of viewing are discussed.     

Ceramic pigments of the brown spectrum based on galvanic slime

The possibility of synthesizing pigments of the brown spectrum on the basis of galvanic slime is investigated. The color characteristics of the pigments, their phase compositions, and coloring capacity in overglaze paints and glazes are investigated.Translated from Steklo i Keramika, No. 4, pp. 3–7, April, 1995.     

Calcium sulphate as pigment for improved functional properties of coated paper

In the last few years, interest and demand of high bright paper have forced paper manufacturers to think new ways to improve brightness and whiteness of coated paper. Pigment coating is widely used to enhance the optical properties such as brightness, whiteness, and gloss of paper and paperboard. These optical properties are the most important for end user and also determine the final cost of coated paper. Calcium sulphate has inherent better optical properties compared to other conventional pigments for example ground calcium carbonate, precipitated calcium carbonate and kaolin clay. The present study was carried out with an aim to synthesize calcium sulphate using waste procured from phosphoric acid industry and to study its impact on the rheology of coating color as well as optical properties of coated paper. Addition of calcium sulphate improved the water retention property of coating color which can be helpful for improving the machine runnability. The results also revealed that calcium sulphate can be used as a pigment to produce coated paper of high brightness and whiteness. The brightness and whiteness of the coated paper were improved 4 and 15 points, respectively by using 50 parts of calcium sulphate as a pigment replacing clay from the coating formulation. The surface strength in terms of IGT pick value of coated sheets was found significantly comparable using calcium sulphate as pigment. The print gloss results were observed analogous with matt grade coated paper.     

Effect of different polymers on the efficiency of water‐borne methyl amine adduct as corrosion inhibitor for surface coatings

Styrene/acrylic emulsion copolymer and water‐based short oil urethane alkyd resin were used as binders to prepare water‐based, environmentally friendly paints by using 0.5% emulsified methylamine adduct as corrosion inhibitor. The choice of the two above‐mentioned binders was based on the fact that styrene/acrylic emulsion copolymer is a nonconvertible binder, whereas short oil urethane alkyd resin is a convertible binder. The physical, chemical, mechanical, and corrosion properties of the paint films were evaluated and compared with a commercially known anticorrosive water‐based paint. It was found that the prepared paints have unique desirable properties such as the following: they do not contain anticorrosive pigments (which contain heavy metals in their main chemical structure); they are solvent‐free; and they can be produced to match any color. Corrosion tests on the films of the formulated paints revealed that the short oil urethane alkyd resin is superior to the styrene/acrylic copolymer. Moreover, the corrosion inhibition properties of the paint films prepared from both binders are comparable with the commercially available paints containing anticorrosive pigments. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 879–885, 2002     

Relationship between brightness/luminance ratio and additivity‐law failure

The degree of additivity‐law failure of a mixture color consisting of two component chromatic colors has very complex characteristics depending on the used component colors and their mixing conditions. It is significantly affected by the mixture‐color chromaticity and by the brightness/luminance ratio at the chromaticity. A simple relationship was derived between the following quantities: degree of additivity‐law failure, additivity‐law luminance (luminance of the mixture color derived by postulating additivity law), and brightness/luminance ratio at the chromaticity of the mixture color. This relationship can be applied to any additivity‐law failure experiment and any formula on brightness/luminance ratio. © 2002 Wiley Periodicals, Inc. Col Res Appl, 27, 185–190, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/col.10045     

色粉对聚丙烯复合材料激光打标的影响

为研究配色聚丙烯(PP)复合材料中色粉对激光打标效果的影响,以PP为基体,云母、抗氧剂等为添加成分,以酞青蓝、酞青绿、炭黑和钛白粉为色粉成分,通过熔融共混、注塑成型制备了PP复合材料样板。通过激光打标制备了复合材料标记板,采用色差仪评价了标记板激光打标前后明暗度的变化和打标前后色差的变化。研究了酞青蓝、酞青绿、炭黑和钛白粉含量对激光打标效果的影响。结果表明,酞青蓝、酞青绿和钛白粉均对激光打标具有两面性,少量添加可减弱激光打标效果,含量提高后可通过自身颜色与样板颜色的差异减弱对激光打标效果的影响;炭黑含量越高,打标效果越差。