Spectrophotometer Colour Measurement in Textile Quality Control
Objective colour measurement replaces opinion with numbers, but the numbers only work when the measurement conditions are fixed.
This article sets out what the requirement involves, how to specify it and how to verify it before bulk production.
Instrument basics
A spectrophotometer measures reflectance across wavelengths and converts it into colour values such as L, a, b.
Experience shows that small specification decisions here have an outsized effect on the customer experience.
Colour difference metrics
DE values express the difference from the standard, and tolerance limits should be agreed in writing.
Write the requirement into the fabric specification as a numeric range with the test method named, so buyer and mill measure the same thing.
- Ask for a separate price line for the requirement
- Confirm minimum quantities before committing the colourway
- Build one extra approval round into the calendar
Measurement conditions
Aperture size, ultraviolet setting, light source and sample preparation must be identical for buyer and supplier.
Escalate deviations immediately, as a small change early in the run is cheap to correct and costly to fix later.
Metamerism checking
Comparing values under multiple light sources reveals shades that match in one light only.
Share the results with the mill, since transparency usually shortens the path to a workable solution.
- Confirm the numeric range and the test method in the specification
- Keep an approved physical standard at the machine
- Retest after the agreed care regime before shipping
Workflow integration
Measuring recipe trials and bulk batches shortens approvals and reduces argument about visual assessment.
Document what is included in the price, including testing, packing and documentation, to keep comparisons fair.
Summary
A clear specification, a trained operator and a documented test together remove most of the risk from this part of the programme.
