Another way to display the a* and b*-axes is the representation in polar coordinates.
C* is named Chroma and shows the difference from the neutral gray axis to the sample.
H is called the Hue angle. It is always measured counter-clockwise starting from the positive a*-axis.
This set of definitions is mainly used for saturated colors, since values in numbers are easier to understand. For instance, the color orange is more saturated than the sample, not more red and more yellow. The difference from a sample to the standard is stated in delta values (Δ or d):
ΔL* = 0,5 sample is 0.5 units brighter
Δa* = -1,5 sample is -1.5 units greener
Δb* = -3,6 sample is -3.6 units bluer
ΔC* = -3,9 sample is -3.9 units less colored
ΔH = 0,7 sample is 0.7 depends on the location