CRANE R&D Equipment

Colorimetry & Gloss
Objective: Gloss is measured using a gloss meter, which directs a light at the surface of a sample at a defined angle and measures the amount of reflected light at an equal angle. Measurement units are equipped with standard geometries of 20°, 60° or 85°. For improved accuracy of measurement it is recommended to use the 20° geometry for surfaces with gloss greater than 70 GU, the 60° geometry for surfaces between 10-70 GU, and the 85°geometry for surfaces less than 10 GU. Crane uses the 60° measurement for all products. All gloss levels can be measured using this standard measurement angle of 60°.

Crane utilizes the CIELab color system combines the data of the 3 elements; light source, observer, and object. The two axes of a* (-green / + red) and b* (-blue / + yellow) represent color. The third axis is L* is used to define brightness (0=pure black / 100=pure white). Every color can be specified with the coordinates L*a*b*. Color is communicated in terms of difference ‘delta or Δ’; such as ΔL*, Δa*, and Δb*. Total change of a color is represented by a single value delta E* (ΔE*). The ΔE* calculation is the square root of (ΔL*) 2 + (Δa*) 2 + (Δb*) 2. Color manufacturing tolerances are defined as a ΔE* values.