Pair comparisons were used to assess the perceptual uniformity of the Munsell value (<i>V</i>) and chroma (<i>C</i>) scales near 5<i>Y</i> 7.5/1 for both small (0.25–0.75) and larger (1–2) increments in <i>V</i> and <i>C</i>. We conclude that in this region perceptual linearity is retained down to steps of 0.25 <i>V</i> or <i>C</i>. Bisection experiments showed that around IOR 7/8 perceptual linearity in Munsell hue (<i>H</i>), <i>V</i>, and <i>C</i> was retained down to step sizes of 0.25 H, 0.10 <i>V</i>, and 0.25 <i>C</i>.
Robert T. Marcus and Fred W. Billmeyer, Jr., "Step size in the Munsell color-order system by pair comparisons near 5 Y 7.5/1 and bisections near 10R 7/8," J. Opt. Soc. Am. 65, 208-212 (1975)