Upon graduation MacAdam joined the
Research Laboratories of the Eastman Kodak company in
Rochester, New York. He retired from the company in 1975. Subsequently, he was named adjunct professor at the
University of Rochester, Institute of Optics where he remained active until 1995. At Eastman Kodak, among many other things, he helped to establish the theoretical basis for
color photography, 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 raised over the
CIE chromaticity diagram, using the newly established
CIE standard observer and
illuminant C and A data from 1932.
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). 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.
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 of phases of daylight of various correlated
color temperatures, 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 that in 1947, at the suggestion of the
U.S. National Research Council, began work on a perceptually uniform colorimetric
model 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==