Image Analysis Tools to Quantify Visual Properties of Hair Fiber Assemblies 328 height is much greater in the latter case. In fact, measurements revealed an average peak height of 110.29±20.47 and 165.22±33.38 for untreated and mascara treated eyelashes, respectively. The peak height was calculated by subtracting the minimum value of a negative peak from 255, which corresponds to the highest possible luminosity value. This certainly demonstrates the ability of mascaras to emphasize eyelashes by making them darker due to the pigment in the mascara and more distinguishable by binding multiple fibers together. Figure 14. (a) Circumferential measurement of luminosity across a series of eyelash fibers corresponding to the cross-sectional view looking down the axis of the mounting cylinder. Plots of luminosity as a function of distance for (a) untreated and (b) mascara treated eyelashes