David Lewis MacAdam (July 1, 1910 – March 9, 1998) was an American

physicist A physicist is a scientist who specializes in the field of physics, which encompasses the interactions of matter and energy at all length and time scales in the physical universe. Physicists generally are interested in the root or ultimate cau ...

and color

scientist A scientist is a person who Scientific method, researches to advance knowledge in an Branches of science, area of the natural sciences. In classical antiquity, there was no real ancient analog of a modern scientist. Instead, philosophers engag ...

who made important contributions to color science and technology in the fields of colorimetry, color discrimination,

color photography Color photography (also spelled as colour photography in English in the Commonwealth of Nations, Commonwealth English) is photography that uses media capable of capturing and reproducing colors. By contrast, black-and-white or gray-monochrome ...

and

television Television (TV) is a telecommunication medium for transmitting moving images and sound. Additionally, the term can refer to a physical television set rather than the medium of transmission. Television is a mass medium for advertising, ...

, and color order.

Education

MacAdam grew up in

Upper Darby Township, Pennsylvania Upper Darby Township, often shortened to Upper Darby, is a Home Rule Municipality (Pennsylvania), home rule Township (Pennsylvania), township in Delaware County, Pennsylvania, United States. As of the 2020 census, the township had a total popul ...

, where he graduated from

Upper Darby High School Upper Darby High School (UDHS) is a four-year public high school located in Upper Darby Township in Delaware County, Pennsylvania. It is part of the Upper Darby School District. Established in 1895, it is the oldest high school in Delaware Count ...

in 1928. He attended

Lehigh University Lehigh University (LU), in Bethlehem, Pennsylvania, United States, is a private university, private research university. The university was established in 1865 by businessman Asa Packer. Lehigh University's undergraduate programs have been mixed ...

Bethlehem, Pennsylvania Bethlehem is a city in Northampton County, Pennsylvania, Northampton and Lehigh County, Pennsylvania, Lehigh counties in the Lehigh Valley region of eastern Pennsylvania, United States. As of the 2020 United States census, 2020 census, Bethle ...

. In 1936, he received a PhD in physics from

MIT The Massachusetts Institute of Technology (MIT) is a private research university in Cambridge, Massachusetts, United States. Established in 1861, MIT has played a significant role in the development of many areas of modern technology and sc ...

. Under Prof. Arthur C. Hardy, he originated the first course in color measurement and assisted Hardy in the preparation of “Handbook of Colorimetry,” published in 1936.

Career

Upon graduation MacAdam joined the Research Laboratories of the Eastman Kodak company in

Rochester, New York Rochester is a city in and the county seat, seat of government of Monroe County, New York, United States. It is the List of municipalities in New York, fourth-most populous city and 10th most-populated municipality in New York, with a populati ...

. He retired from the company in 1975. Subsequently, he was named adjunct professor at the

University of Rochester The University of Rochester is a private university, private research university in Rochester, New York, United States. It was founded in 1850 and moved into its current campus, next to the Genesee River in 1930. With approximately 30,000 full ...

, Institute of Optics where he remained active until 1995. At Eastman Kodak, among many other things, he helped to establish the theoretical basis for

, including color masking as compensation for unwanted dye layer absorptions.

Optimal object color limits

While still studying, MacAdam published in 1935 two papers on the theory of optimal object colors in which he showed the results of his calculations of the optimal object

color solid A color solid is the Three-dimensional space, three-dimensional representation of a color space or Color model, model and can be thought as an analog of, for example, the One-dimensional space, one-dimensional color wheel, which depicts the v ...

raised over the CIE chromaticity diagram, using the newly established CIE standard observer and illuminant C and A data from 1932. CIExy1931 MacAdam

MacAdam ellipses

One of MacAdam's best known contributions was in support of technological color control. Assuming that the basis of color difference perception was the statistical error in matching the appearance of a given color stimulus he conducted an extensive experiment with one observer, the result of which was expressed in the CIE chromaticity diagram in form of statistically derived ellipses, published in 1942 (See Fig. 1).Visual sensitivities to color differences in daylight, ''Journal of the Optical Society of America'', 32, 1942, 247–274. However, the resulting Friele–MacAdam–Chickering color difference formula proved less effective in predicting perceived color differences than formulas derived on other bases. In attempting to convert the ellipses to circles of equal size MacAdam encountered the non- Euclidean nature of psychophysical

color space A color space is a specific organization of colors. In combination with color profiling supported by various physical devices, it supports reproducible representations of colorwhether such representation entails an analog or a digital represe ...

Instrumentation and computation

In the mid-1940s MacAdam pioneered the use of computers in colorimetric computations, established Hardy's reflectance spectrophotometer as a reliable industrial measuring instrument, and invented a tristimulus integrator as an accessory.

Principal component analysis of daylight

With Deane B. Judd and Günter Wyszecki, MacAdam performed the first

principal component analysis Principal component analysis (PCA) is a linear dimensionality reduction technique with applications in exploratory data analysis, visualization and data preprocessing. The data is linearly transformed onto a new coordinate system such that th ...

of phases of daylight of various correlated

color temperature Color temperature is a parameter describing the color of a visible light source by comparing it to the color of light emitted by an idealized opaque, non-reflective body. The temperature of the ideal emitter that matches the color most clos ...

s, demonstrating that they can be represented as linear combinations of a limited number of spectral components.

Optical Society of America Uniform Color Scales

MacAdam was a leading member of the committee of the

Optical Society of America Optica, founded as the Optical Society of America (later the Optical Society), is a professional society of individuals and companies with an interest in optics and photonics. It publishes journals, organizes conferences and exhibitions, and ca ...

that in 1947, at the suggestion of the

U.S. National Research Council The National Academies of Sciences, Engineering, and Medicine (NASEM), also known as the National Academies, is a Congressional charter, congressionally chartered organization that serves as the collective scientific national academy of the Uni ...

, began work on a perceptually uniform colorimetric

model A model is an informative representation of an object, person, or system. The term originally denoted the plans of a building in late 16th-century English, and derived via French and Italian ultimately from Latin , . Models can be divided in ...

of the color solid. Upon the retirement of its first chairman D. B. Judd, MacAdam was elected chair. The result of the committee's work was published in 1974 as ‘Uniform Color Scales,’ with OSA publishing a related color atlas with 558 samples in 1977.

Publications

In addition to his contributions to ''Handbook of Colorimetry'' (1936) he was a major contributor to OSA's 1953 book ''The Science of Color''. His interest in the history of color science resulted in publication in 1970 of ''Sources of Color Science'', a compilation of 26 seminal papers on color science, from

Plato Plato ( ; Greek language, Greek: , ; born BC, died 348/347 BC) was an ancient Greek philosopher of the Classical Greece, Classical period who is considered a foundational thinker in Western philosophy and an innovator of the writte ...

Le Gros Clark Sir Wilfrid Edward Le Gros Clark (5 June 1895 – 28 June 1971) was a British anatomist, surgeon, primatologist and palaeoanthropologist, today best remembered for his contribution to the study of human evolution. He was Dr Lee's Professor of A ...

, several translated for the first time into English. In 1981 he published ''Color Measurement: Theme and Variations'', a presentation of fields of color science in which he has made important contributions.''Color Measurement: Theme and Variations'', New York: Springer Verlag, 1981 He is also the author of some 100 peer-reviewed journal articles. MacAdam was president of the Optical Society of America in 1963 and editor of the ''

Journal of the Optical Society of America The ''Journal of the Optical Society of America'' is a peer-reviewed scientific journal of optics, published by Optica. It was established in 1917 and in 1984 was split into two parts, A and B. ''Journal of the Optical Society of America A'' ...

'' from 1964 to 1975. He was active in the Inter-Society Color Council and the Commission Internationale de l’Eclairage (CIE). He received honors from many societies, including the Frederic Ives Medal of the Optical Society of America in 1974.