Spacing defined by various Munsell hue and chroma steps are analyzed, applying diagrams resulting from transformations between the Coloroid and the Munsell color systems, displaying colors of both color systems with the same Y tristimulus values. After comments on spacings derived from identities, similarities and differences between both color systems, unevennesses uninterpretable from differences of color system constructions are attributed either to uniform variation of color stimuli followed by uneven variation of color perceptions, or to uncertainties of human color perception at several spots of the color space sufficient to be noticeable in spacings in perceptually uniform color systems, such as the Munsell color order system.