Describing color differences
Lesson 3 of 4
Objective
Describe a color difference precisely and choose the correct assessment tool for the question being asked.
Separate your observations: is the sample lighter or darker; which direction has the hue moved (redder, yellower, greener, bluer); and is it brighter or duller (chroma)? These are different observations and should be recorded separately.
Gray scales are physical reference tools used under the current procedure. The gray scale for color change is used to rate how much a specimen has changed compared with its original. The gray scale for staining is used to rate how much color has transferred onto an adjacent fabric. They are different tools for different questions. A gray scale rates the overall magnitude of a visual difference — it is not a tool that only measures lightness.
Instrumental measurement (a spectrophotometer) and visual assessment have their own methods and limitations. There is no universal numerical color-difference limit; any instrumental tolerance must come from the applicable Brand requirement.
Factory scenario: 'it looks a bit off'
A line checker reports a sleeve as 'off shade'. The inspector re-examines under the specified source and records: sleeve slightly darker and slightly redder than the body; chroma similar.
That precise description lets the quality lead compare it with the Brand criteria and the shade band instead of guessing.
Common mistakes
- Using the staining scale to rate color change, or the reverse.
- Using a printed or on-screen gray scale instead of the physical scale.
- Quoting a universal number as a pass limit.
Your action
Compare two items of similar color you have nearby and write three separate observations: lightness, hue direction and chroma.