Metamerism, A Play of Light

Particularly meddlesome for those who handle color daily, such as painters, restorers and designers, metamerism also affects the world of fashion. Under different lighting conditions, two fabrics that appear the same can suddenly diverge.
Our current palette eclipses the distant, bland memory of the Middle Ages that was dominated by beiges and browns. At the time, color distinguished class more so than fabric until the arrival of silk near the end of the epoch. Despite some grey areas, the history of color begins with the first humans and has moved to the irregular rhythm of chances, opportunities, discoveries, approximations, and changing zeitgeists.
From natural dyes to artificial colorants discovered via organic chemistry, colors have considerably gained in intensity and range alike. The first colored compounds were derived from aniline, discovered in the 19th century by German chemist August Wilhelm von Hofmann. His student, William Perkin, developed the first dye from aniline, called mauveine.
The chemistry of coal and oil alike have opened an immense range of colors that were previously unattainable but now applicable to a wide range of fabrics. This has incredibly bolstered the development of fashion, for it is necessary to go through artifice to attain representation of natural colors; plant extracts themselves do not lead to the reproduction of floral flamboyance.
Still, color is nothing without light. It is light that births color and controls its intensity. It was thought to be enough to master colorants, but alas. Every person has observed metamerism, perhaps without naming or explaining the phenomenon. It is the ability of a color to modify its visual aspects under different lighting circumstances. The same sample will be perceived as different colors by the human eye as a function of lighting; this sensitivity varies between individuals’ eyes.
The metamerist phenomenon is directly linked to the spectral distribution of a light source. Color is simply the reflection of the wavelengths produced by light and is dependent on the absorptive and reflective capacities of a surface material. Two metameric or homochromic colors can converge and diverge according to lighting. They are distinct in their physical spectrums but the human eye, despite these distinctions, is unable to differentiate between them in a given lighting scenario.
This phenomenon occurs with colors and pigments that differ in spectral composition. In the face of the effect, the colors are not equivalent. Brown, mauve, lilac, grey and grey-blues are often subject to metamerism, as well as very saturated hues of red, orange, green and blue.
Photo Credit: Dan Brady