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K. S. GIBSON AND D. NICKERSON
this relation all of the 1919 and 1926 data for the chromatic samples have been plotted on the (x, y)-diagram shown in Fig. 4. To assist in an evaluation of any consistent or erratic differences among the data two straight lines are plotted for each Munsell hue designation: First, a dashed line passing from the 5/5 point for each of the five principal hues through the point representing I.C.I. Illuminant C and on to the complementary; and second, a continuous line passing from the same 5/5 point through the point (DM) which results from disk mixture of these five principal hues in equal proportions.[1]
Fig. 4. Trichromatic coefficients (trilinear coordinates) of Munsell Atlas samples as obtained from measurements made in 1919 and 1926. Also shown in this figure are the complements of the 5/5 R, Y, G, B, and P colors derived from Eqs. [5], both with I.C.I. Illuminant C as the neutral point and with the disk-mixture (DM) color as the neutral point. Note the regularity of the ten-sided figure (continuous lines) resulting from use of the DM point as compared with that (dashed lines) based on C. Each pair of points representing the experimental data is connected to a point (X) on the line joining the DM and the respective 5/5 points, these X-points being computed by Eqs. [5] and [6] for the given values of V/C.
- ↑ Having first multiplied each (X, Y, Z)-triad by factors to make Y=0.25, as suggested by Tyler and Hardy, reference 11.
