scholarly journals Exploring the Limits of Color Accuracy in Technical Photography

2021 ◽  
Author(s):  
Eric Kirchner ◽  
Carola van Wijk ◽  
Henni van Beek ◽  
Tammo Koster
Keyword(s):  
Reference Data ◽  
Digital Photography ◽  
Color Difference ◽  
Art Collections ◽  
Color Representation ◽  
Average Color ◽  
Art Objects ◽  
Art Works ◽  
The Common ◽  
Black Color

Abstract The growing importance of publishing art collections online has led to increasingly strict tolerances on digital photography of art objects. There are two internationally recognized sets of guidelines for creating high-quality digital images, Metamorfoze and FADGI. These guidelines require using sets of standardized color patches in museal photography. The X-Rite ColorChecker SG chart with 140 color patches is often used. Recent studies showed that even in the standardized conditions of museum photography studios it is often very difficult to satisfy the strictest guidelines on color accuracy for camera profiling, with no indications for improvements.Here we report results of our investigation into the bottlenecks in achieving high color accuracy. We show that a large part of the color deviations originates from the 15 black color patches of the ColorChecker SG chart. These patches have a large impact on the average color deviation and the maximum color deviation that are the performance measures for color accuracy in the FADGI and Metamorfoze guidelines. We show that spectrophotometer measurements for the black patches produce color deviations dE(CIE 1976) ranging from 3.7 to 5.2 with respect to reference data, making it impossible to meet the strictest Metamorfoze guidelines. The black patches push the average color difference CIEDE2000 from 0.59 to 0.82 with respect to reference data already when using spectrophotometer data. Since the strictest FADGI guidelines prescribe an average CIEDE2000=2.0, this leaves little tolerance for errors due to lighting and camera profile. Our results indicate that the common practice of manually tweaking camera profiles until the software suggests sufficient color accuracy is obtained with respect to suppliers’ reference data often does not improve color representation but makes it worse, especially for representing dark nuances. This is unfortunate for example for the digital photography of 17th century Dutch paintings, where dark passages occupy large areas of the art works. We show that the key step in achieving color accurate digital photography is to use customer reference data rather than commonly used generic reference data. We explain the results by investigating not only the color properties of the ColorChecker SG chart, but also its glossiness.

scholarly journals Exploring the limits of color accuracy in technical photography

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Eric Kirchner ◽  
Carola van Wijk ◽  
Henni van Beek ◽  
Tammo Koster
Keyword(s):  
Reference Data ◽  
Digital Photography ◽  
Color Difference ◽  
Art Collections ◽  
Color Representation ◽  
Average Color ◽  
Art Objects ◽  
Art Works ◽  
The Common ◽  
Black Color

AbstractThe growing importance of publishing art collections online has led to increasingly strict tolerances on digital photography of art objects. There are two internationally recognized sets of guidelines for creating high-quality digital images, Metamorfoze and FADGI. These guidelines require using sets of standardized color patches in museal photography. The X-Rite ColorChecker SG chart with 140 color patches is often used. Recent studies showed that even in standardized conditions it is often difficult to satisfy the strictest guidelines on color accuracy for camera profiling, with no indications for improvements. We report results of our investigation into the bottlenecks in achieving high color accuracy. We show that a large part of the color deviations originates from the 15 black color patches of the ColorChecker SG chart. These patches have a large impact on the average color deviation and the maximum color deviation that are the performance measures for color accuracy in the FADGI and Metamorfoze guidelines. We show that spectrophotometer measurements for the black patches produce color deviations dE(CIE 1976) ranging from 3.7 to 5.2 with respect to reference data, making it impossible to meet the strictest Metamorfoze guidelines. The black patches push the average color difference CIEDE2000 from 0.59 to 0.82 with respect to reference data already when using spectrophotometer data. Since the strictest FADGI guidelines prescribe an average CIEDE2000 = 2.0, this leaves little tolerance for errors due to lighting and camera profile. Our results indicate that the common practice of manually tweaking camera profiles until software suggests sufficient color accuracy is obtained with respect to suppliers’ reference data often does not improve color representation but makes it worse, especially for representing dark nuances. This is unfortunate for example for the digital photography of seventeenth century Dutch paintings, where dark passages occupy large areas of the art works. We show that the key step in achieving color accurate digital photography is to use customer reference data rather than commonly used generic reference data. We explain the results by investigating not only the color properties of the ColorChecker SG chart, but also its glossiness.

The Japan Art Documentation Society and art librarianship in Japan today

1989 ◽  
Vol 14 (3) ◽  
pp. 5-6 ◽  
Author(s):  
Takeshi Mizutani
Keyword(s):  
Collective Response ◽  
Art Objects ◽  
Museum Professionals ◽  
Common Interests ◽  
The Common ◽  
Integrated Concept

The Japan Art Documentation Society (JADS) was founded in April. Inspired by developments both within Japan and abroad, and by the IFLA Section of Art Libraries, JADS has set out to embrace the common interests of library and museum professionals as represented by an integrated concept of “art documentation”. Essentially, the Society represents a collective response to the challenge and potential of the computer - to the benefits it can bring to, and the methodologies it requires of, the organising of art objects, art images, and art information. (The Society’s “prospectus”, from its first Newsletter, is appended).

Subjective Sensation of Color Differences – Determination of Thresholds Depending on Color Tones and Resolution

2015 ◽  
Vol 21 (1) ◽  
pp. 21-27 ◽  
Author(s):  
Christian Brischke ◽  
Tanja Borcharding ◽  
Uta Mengel
Keyword(s):  
Color Space ◽  
Color Difference ◽  
Threshold Values ◽  
Color Tone ◽  
Color Changes ◽  
Art Objects ◽  
Color Differences ◽  
Subjective Sensation ◽  
Total Color Difference

Abstract Colors are frequently defined by three points on the L*a*b* coordinates of the CIELAB color space, and the distance between two colors can be expressed as the total color difference ΔE. In particular with respect to reproducibility of print media color differences are an important parameter, as well as for car finishes and textile dyes. Color changes are also the result of ageing and weathering which is an issue for art objects and in the building and restoration sector. However, the subjective perceptibility of color differences depends on numerous factors and general thresholds are difficult to define. This study aimed therefore on defining tolerance levels for color changes in dependence of color tones and color tone combinations as well as their resolution. In total 30 test persons evaluated samples, which had been painted with acrylic artist colors with defined color differences (ΔE = 0–7). The test subjects realized color differences already at ΔE = 1–4 for the highest resolution. Threshold values have been identified for different tones as well as the effect of interdependencies between tones and the level of color heterogeneity between adjacent areas.

The Fatal Paracetamol Dosage — How Low Can You Go?

1992 ◽  
Vol 32 (4) ◽  
pp. 303-310 ◽  
Author(s):  
F Patel
Keyword(s):  
Blood Level ◽  
Reference Data ◽  
Common Knowledge ◽  
Paracetamol Poisoning ◽  
Minimal Dose ◽  
The Common ◽  
Popular Texts ◽  
Proper Interpretation ◽  
Full Consideration ◽  
Daily Total

Popular texts and forensic literature pertaining to paracetamol toxicology advocate an acceptable minimal dose or lower limit of the blood level ‘normally’ associated with a fatal single overdose. A case of fatal, acute paracetamol poisoning from a minimal single dose, within the recommended therapeutic daily total and associated with a zero blood paracetamol level, is reported. It also emphasizes the common knowledge that the toxicological tabulated reference data available on fatal levels of most drugs is merely a guide. The proper interpretation of the analytical results thus requires the full consideration of the circumstances surrounding the death in each case. The clinico-pathophysiology and toxicology of paracetamol poisoning is briefly reviewed in an attempt to establish how low a fatal paracetamol dosage can go. The phenomenon of fatal dose and blood level is in a paracetamol limbo.

Partitioning biochemical reference data intosubgroups: comparison of existing methods

2004 ◽  
Vol 42 (7) ◽  
Author(s):  
Ari Lahti
Keyword(s):  
Reference Data ◽  
Reference Interval ◽  
Reference Intervals ◽  
New Method ◽  
Poor Correlation ◽  
Specific Reference ◽  
Common Reference ◽  
Reference Limits ◽  
The Common ◽  
The Ideal

AbstractFour existing methods for partitioning biochemical reference data into subgroups are compared. Two of these, the method of Sinton et al. and that of Ichihara and Kawai, are based on a quotient of a difference between the subgroups and the reference interval for the combined distribution. The criterion of Sinton et al. appears rather stringent and could lead to recommendations to apply a common reference interval in many cases where establishment of group-specific reference intervals would be more useful. The method of Ichihara and Kawai is similar to that of Sinton et al., but their criterion, based on a quantity derived from between-group and within-group variances, seems to lead to inconsistent results when applied to some model cases. These two methods have the common weakness of using gross differences between subgroup distributions as an indicator of differences between their reference limits, while distributions with different means can actually have equal reference limits and those with equal means can have different reference limits. The idea of Harris and Boyd to require that the proportions of the subgroup distributions outside the common reference limits be kept reasonably close to the ideal value of 2.5% as a prerequisite for using common reference limits seems to have been a major improvement. The other two methods considered, that of Harris and Boyd and the “new method” follow this idea. The partitioning criteria of Harris and Boyd have previously been shown to provide a poor correlation to those proportions, however, and the weaknesses of their method are summarized in a list of five drawbacks. Different versions of the new method offer improvements to these drawbacks.

scholarly journals Weighing Down the Landscape: The Quarry as a Site of Rural Modernity

2018 ◽  
pp. 69-83
Author(s):  
Samuel Shaw
Keyword(s):  
Twentieth Century ◽  
Close Relation ◽  
Art Galleries ◽  
Wide Range ◽  
Art Works ◽  
History Of ◽  
The Common ◽  
Late Nineteenth ◽  
A Site ◽  
Rural Industries

This chapter argues that late nineteenth- and early twentieth-century artists seem to have been especially attracted by quarries, treating them as a means of exploring modernity through the lens of rural romanticism. Quarries regularly appear in paintings in many of the artists associated with rural modernity: William Rothenstein, Edward Wadsworth, Walter Bell, Roger Fry, and J. D. Fergusson, among them. Appreciating that there is no single way of categorising and representing quarries, this chapter (the first ever study of this important subject) explores many of the common themes to be found in paintings of quarries in the first half of the twentieth century. It considers a wide range of artists and art-works — the majority of which are owned by rural art galleries — in close relation to the history of rural industries in such regions as Cornwall, West Yorkshire, and Edinburgh.

scholarly journals ORION—Art Collections and Collectors in Portugal

Heritage ◽  
2019 ◽  
Vol 2 (2) ◽  
pp. 1045-1059
Author(s):  
Vera Mariz ◽  
Rosário Salema de Carvalho ◽  
Fernando Cabral ◽  
Maria Neto ◽  
Clara Moura Soares ◽  
...  
Keyword(s):  
Database Management System ◽  
Controlled Vocabulary ◽  
International Standards ◽  
Art Collections ◽  
Relational Capacity ◽  
History Of Collecting ◽  
Art Objects ◽  
History Of ◽  
One Step ◽  
New Research

ORION is a digital art history research-oriented project focused on the study of art collections and collectors in Portugal, supported on a relational database management system. Besides the obvious advantage of organizing and systematizing an enormous amount of information, promoting its analysis, this database was specifically designed to highlight the relationships between data. Its relational capacity is not only one of the most relevant features of ORION, but a differentiating quality, one step forward in comparison to other international databases and studies that use digital methodologies. This article discusses the methods and the advantages of using ORION in research related to the history of collecting, art markets and provenance of art objects in Portugal, where it is the very first time that an approach such as this is intended, looking for a systematization of data that paves the way to the emergence of new research questions. Furthermore, and because ORION aims to share the data and knowledge with other projects, institutions and researchers, the database uses different international standards, such as data structure (CIDOC-OIC and Getty-CDWA), controlled vocabulary (Iconclass, Art and Architecture Thesaurus (AAT), Thesaurus of Geographic Names (TGN), and Union List of Artist Names (ULAN)) and communication and exchange of information (CIDOC-CRM).

Arbiters of Value: The Nationalization of Art and the Politics of Expertise in Early Socialist Romania

2019 ◽  
Vol 33 (3) ◽  
pp. 656-676
Author(s):  
Emanuela Grama
Keyword(s):  
Interwar Period ◽  
Public And Private ◽  
Art Collections ◽  
National Network ◽  
The Public ◽  
Art Objects ◽  
Spatial Dimensions ◽  
The Masses ◽  
Private Collections ◽  
Art Experts

In 1948, immediately after the Communist Party came to power in Romania, state officials commissioned a group of art experts to radically transform the existing public and private art collections into a national system of museums. These professionals became the new regime’s arbiters of value: the ultimate authority in assessing the cultural and financial value of artwork, and thus deciding their fate and final location. Newly available archival evidence reveals the specific strategies that they employed, and the particular political needs of the state they were able to capitalize on in order to survive and even thrive under a regime that, in principle, should have disavowed them. Even though many of them had professionally come of age during the interwar period, the art experts managed to make themselves indispensable to the new state. They functioned as a pivotal mediator between state officials and a broader public because they knew how to use the national network of museums to put the new state on display. Through the rearrangement of public and private collections across the country, and the centralization of art in museums, they produced a particular “order of things” meant not only to entice the public to view the socialist state as the pinnacle of progress and as a benefactor to the masses but also to validate their expertise and forge a new political trajectory for themselves. The strategic movement of art objects that they orchestrated reveals the material and spatial dimensions of state-making in early socialism.

The optimization of color-prediction models for colored cotton fiber yarns

2019 ◽  
Vol 89 (19-20) ◽  
pp. 4007-4014 ◽  
Author(s):  
Liu Yang ◽  
Jing Bai ◽  
Ruiyun Zhang ◽  
Yi Ding ◽  
Feng Ji ◽  
...  
Keyword(s):  
Prediction Models ◽  
Color Difference ◽  
Color Measurement ◽  
Target Color ◽  
Color Matching ◽  
Average Color ◽  
Color Differences ◽  
Computer Aided ◽  
Colored Cotton ◽  
Color Prediction

Color matching is necessary in the manufacture of colored fiber yarns, and its accuracy is one of the main goals in computer-aided color matching. A limited number of pre-colored fibers are blended to match the target color through predicted recipes. Of the color-prediction models applied in computer-aided color matching, two common ones, Stearns-Noechel and Friele, were selected to be modified to improve the color-prediction accuracy in this paper. The models were modified in three ways, in which the pending parameters in the models were determined through statistical analysis depending on median, wavelength, and components; thus, the Stearns-Noechel model was modified to Stearns-Noechel 1, Stearns-Noechel 2, and Stearns-Noechel 3, and the Friele model was modified to Friele 1, Friele 2, and Friele 3. The six modified models were affirmed through 261 colored fiber yarns prepared from five primary cotton fibers, including two-, three-, four-, and five-primary blends. The prediction results of 261 samples showed that Stearns-Noechel 3 had the highest accuracy among the modified Stearns-Noechel models, especially for four-primary blends with an average color difference of 0.50 Color Measurement Committee (CMC) (2:1) units, whereas Friele 1 had the highest accuracy among the modified Friele models, especially for five-primary blends with an average color difference of 0.46 CMC (2:1) units. These results indicate the modified model Stearns-Noechel 3 can be used in color prediction when there are fewer than five yarn components, and Friele 1 can be used for five components with lower color differences that better meet color-matching requirements in practical production.

scholarly journals Monitoring Of Pollutants In Museum Environment

2015 ◽  
Vol 9 (2) ◽  
pp. 173-180 ◽  
Author(s):  
Budu Ana-Maria ◽  
Sandu Ion
Keyword(s):  
Organic Compounds ◽  
Inorganic Compounds ◽  
Pollution Source ◽  
Direct Reading ◽  
Inorganic Particles ◽  
Skin Cells ◽  
Art Objects ◽  
Art Works ◽  
Materials Used ◽  
Acidic Compounds

Abstract Art works are affected by environmental factors as light, temperature, humidity. Air pollutants are also implicated in their degradation. The pollution in museums has two sources: the air from outside, which brings usually dust and inorganic particles, and the inside sources – the materials used for casings (sealants, textiles placed on the display cases, varnishes, wood) that emanate organic compounds. The dust is composed of particles with a diameter of approximately 2µm or higher, which come from soil (silica) or animal and vegetal residues (skin cells, pollen). They facilitate water condensation on objects surface and biologic attack. The inorganic compounds are a result of materials combustion (SO2, NO2, NO) and in presence of water they form acidic compounds which affect the museum objects. The organic compounds are usually peroxides, acids, phthalates, formaldehyde. The effects of these pollutants are: soiling, surface discolouration, embrittlement, corrosion. Therefore, conservators are interested in monitoring the pollution degree in the display cases or in the museum air and in analyzing the effects of pollutants on the exhibited objects. They use different methods for pollutants identification, like direct reading devices based on colorimetry, that can be read after few minutes and hours (they interact with the pollutants in atmosphere), or indirect reading samples that require a laboratory. The information gathered is used for the identification of pollution source and to analyze the concentration of pollutants needed to provoke damages on the surfaces of art objects. This paper is a review of pollutants that affect the art objects and of the monitoring systems used for their identification and measuring.

Sign in / Sign up

Export Citation Format

Share Document