Metamerism is a phenomenon by which a pair of spectrally different samples
match under one illuminant. Metamerism exists
when two materials match under some lighting conditions but not under
other lighting conditions. This can be a serious problem for manufacturers
who combine various parts of different materials or materials from different
sources into one product. A customer expects all the parts of a car that
are the same color to match whether it is a sunny or cloudy day. Someone
who buys a coordinated outfit expects the jacket and slacks to match in
daylight as well as under the fluorescent lights of the department store.
