Navy is a mixture of blue, red and sometimes yellow or black dyes, in very sensitive proportions. A small difference in one dye shifts the cast towards violet, green or grey, and the eye notices such deviations easily on dark shades. Navy also looks different in daylight and artificial light, so the metamerism risk is high.
As a result, two navy lots can look different even when ΔE is small. Approve the lab dip under D65 and a second light, order the whole quantity from one lot, and test rubbing and perspiration fastness, which are critical on dark shades.
navydark shadescolour variation
