pigmented colorants: dependence on media and time - Cornell ...

ials.
In addition, we presented a physically based model to interactively simulate
the appearance of <strong>pigmented</strong> <strong>colorants</strong> using Kubelka Munk theory and modern
graphics hardware. The spectral data is converted into Kubelka Munk absorption
and scattering coefficients. As a result, arbitrary mixtures of pigments that we
have not measured can be simulated. Further, since our data also spans time, the
simulated appearance of these mixtures can be viewed at any point in time.
In our system, other global conditions can also be modified in real time. A
user can instantaneously change the binding media in which the pigments are
suspended–one can simulate the appearance of a work as if were done in oil or
acrylic or another media. Since we compute the lighting calculations from spectra,
the simulated painting can be re-lit under a number of different illuminants, such
as daylight or fluorescent light.
The previous chapter discusses applications for use of this system for the artist
or art historian. Artists that are more aware of their materials will be able to pre-
dict how a color will appear after some time and make adjustments that suit their
creative vision. Restorationists who understand how a color’s underlying materials
change can visualize how an artwork looked in its original brilliance. Conserva-
tionists can predict how long a work can be displayed under natural conditions
before perceptual changes are evident.
Our work has implications in many other industries that utilize <strong>pigmented</strong>
<strong>colorants</strong>. Currently, digital printing inks use primarily dye based inks. Due
to the popularity of digital photography, many individuals are printing on high
quality paper and canvas and framing the pieces. However, dye based inks have a
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longevity of only a few years before serious fading occurs. As a result, <strong>pigmented</strong>