Spectrophotometric Color Tolerance Standards in Bulk Fabric Conversion Runs
Spectrophotometric color tolerancing requires D65 optical calibration, CIEDE2000 ellipsoidal metrics, and strict substrate backing to ensure bulk dye batch agreement.
CMC 2: 1 Tolerance
Calculation Standard
Ellipsoidal color difference formulas determine the acceptability of a dyed batch relative to a master standard. The cmc 2 1 tolerance uses a specific ratio of lightness, chroma, hue and saturation to better match human perception of commercial textile batches. This ratio weightings the lightness component at twice the value of chroma and hue.
Visual Sensitivity
Human eyes detect small differences in lightness more readily than small shifts in color saturation. Because the formula accounts for this, it allows for a larger variation in lightness before a batch is rejected. Soft goods buyers frequently specify this ratio for apparel because it aligns with consumer expectations in retail lighting.
Ellipsoidal Volume
Acceptability is mapped as a three dimensional shape where the boundaries vary depending on the location of the target color in color space. For deep navy or black shades, the volume is smaller than for bright yellow or pale pink. It prevents the acceptance of samples that appear visually different even if their numerical distance from the standard is small.
Darker colors require tighter control because the human eye is more sensitive to lightness shifts in low luminance areas.
Pass Logic
Laboratory technicians use the resulting value to make a binary decision on production lots.