Table 1.
Correlation between ΔE value and sensual difference.

Total color difference (ΔE) Sensual difference
0 ~ 0.5 Trace
0.5 ~ 1.5 Slight
1.5 ~ 3.0 Noticeable
3.0 ~ 6.0 Appreciable
6.0 ~ 12.0 Much
over 12.0 Very much