Scattering characteristics of three model systems analogs to red, green, and white pigments containing non-spherical particles are calculated with the T-matrix method. These scattering parameters are then used to evaluate colorimetric curves of paint films with the multiflux computational technique. Color difference of each system containing different oblate spheroidal-shaped pigments is calculated with reference to systems containing spherical pigments of equivalent volume. Results show that color-difference increases for chromatic pigments as shape of pigments deviates from sphericity. Nonabsorbing particle analogs to titanium dioxide behave like spherical particles, though their shape deviates significantly from sphericity. (C) 2003 Wiley Periodicals, Inc.