Recent algorithms developed in the field of color vision make assumptions based on the spectral reflectance curves of Munsell chips and natural materials. Some of them rely on data collected many years ago. which is partially incomplete in the visible spectrum. or contains many occurrences of the same material in it. In this article. we present a set of new measurements of different materials. In particular. we measured the spectral reflectance of Munsell chips, paints. and various natural materials in the 390–730‐nm range. In addition, we have analyzed. through principal‐component analysis, the possibility of representing the data collected with a set of basis functions. We show the implications of varying the number of principal components used (from 7 down to 3) on the errors introduced using this method.

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Studies of compressed shell integrity of spherical targets on the 60-beam 30 kJ UV OMEGA laser system involve spatially and temporally resolved measurements of core emission at different x-ray energies. Hot-core emission backlights a titanium-doped shell that is imaged at x-ray energies above and below the titanium K edge. The difference between the two images is related to perturbations in the cold, or absorbing, part of the shell. The core emission has been imaged by a pinhole array on a framing camera and recorded on film. The resolution and noise of all parts of the imaging system have been characterized. Using this information, a Wiener filter that reduces noise, compensates for detector resolution, and facilitates measurement of shell nonuniformities has been formulated.