Color Value Scale Calculator

The calculator splits your darkest-to-lightest range into equal Munsell-value increments (Step Increment), then separately converts each of those evenly spaced values into reflectance using the Ladd-Pinney polynomial. Because that value-to-reflectance relationship is a curve rather than a straight line, the reflectance jump between steps is not perfectly even even though the Munsell value jump is — the visual value scale and the physical light-reflectance scale aren't the same shape.

The calculator sums, across all your steps, the portion of each step's equal paint volume attributed to white versus black based on that step's reflectance fraction, then compares those running totals to the White Paint Available and Black Paint Available you entered. A 0 means your on-hand supply of that color falls short of what the full scale would need if you mixed every step at once.

The middle step sits at the visual and tonal center of your range, which typically makes it the hardest one to judge and mix confidently — get the mid-tone wrong and the whole scale's contrast structure reads off, so the calculator surfaces its exact Munsell value and reflectance percentage as the step worth double-checking before you commit paint to canvas.

Treat them as a starting point, not a precise recipe. The ratios come from mapping Munsell reflectance directly onto paint-volume fractions, but real pigments don't blend that way — tinting strength, opacity, and undertone all vary by pigment, so two different whites or blacks can reach the same visual value at different mixing ratios than the calculator predicts.