Record the L*a*b values of the sample and the reference with a calibrated spectrophotometer or colorimeter. Compute the difference in the color by use of ΔE. The lower the Delta E, the more accurate the result. The difference in energy, ΔE < 1, is generally assumed to be invisible to the eye.

A spectrophotometer measures the full visible color spectrum (typically 400–700 nm). It offers significantly higher precision and enables detailed evaluations – including spectral curves, ΔE values, and color distance measurements. It is the preferred choice for demanding applications in labs or color development environments. learn more..

The core difference between a colorimeter and a spectrophotometer lies in their light measurement methods. A colorimeter measures color values based on the tristimulus method (e.g. LAB or RGB) and compares the sample to a reference. It's ideal for quick, repeatable measurements under consistent conditions – such as in production or incoming goods control.

 A gloss meter measures the amount of light reflected from a surface at a specific angle. It's commonly used to assess surface finishes such as paint, coatings, plastics, and paper for consistency, quality control, and visual appearance evaluation.

Samples should be cleaned, dried, and scratched-free to obtain consistent haze measurements.

L*a*b* is an L*a*b* color space. The L* is a measure of lightness (as 0 = black, 100 = white), a* indicates the green to red axis, and b* indicates the blue to yellow axis. It is also common in color measurement in terms of precision and reliability.

When detecting color differences, the first factors to consider when selecting a light source include its stability, directionality, lifespan, and the effectiveness of the ultimately obtained spectral curve. The illuminant of a colorimeter is a fixed bulb, such as a tungsten lamp，LED light or a long-life xenon lamp. However, for the same color sample, the results displayed by the instrument vary under different light sources. This is because different light sources cause different absorption and reflection of light on the sample, leading to differences in how both the human eye and the instrument perceive the color. 

In general, the D65 light source is used in the application of coil steel inks for construction. The D65 light source is equivalent to average daylight. Most coil steel inks for construction are used outdoors, and sunlight is regarded as the standard light source in outdoor environments. For household appliance coil steel inks, due to their usage characteristics, they are mostly used indoors. Therefore, the A standard light source is adopted for color measurement of samples based on indoor lighting conditions. The A light source is a carefully specified tungsten light source. Other light sources, such as fluorescent light sources, can be used in many types of applications. For example, some textile factories use fluorescent light sources. Therefore, a reasonable light source should be selected as the mutually recognized measurement method based on actual usage conditions and user requirements. Once agreed upon by both parties, color measurement must be conducted under the same conditions. This helps reduce unnecessary systematic errors and human errors, achieving the optimal consistency in color measurement. 

The 3nh high-precision spectrophotometric colorimeter adopts a combined LED light source with long lifespan and low power consumption, which includes UV (ultraviolet) and UV-excluded options. This design can meet the color difference detection needs of different users and supports the selection of multiple light source modes.

Usually you will find haze and transmittance standards of ASTM D1003, ISO 13468, & JIS K7105.

The principle of colorimetry is the law of Beer-Lambert, which says that the intensity of light absorbed by a colored solution is proportional to the concentration of the absorbing species and the path length. It measures the extent of light that is absorbed at certain wavelengths.

Techniques of measuring color are visual color comparison, colorimetry (with colorimeters) and spectrophotometry (measuring spectral reflectance), and image analysis. Both techniques measure the reflection or absorption of light by materials and are commonly quantified. Therefore standardized in color spaces such as CIELAB or RGB.

A paint gloss meter is used to measure the level of paint gloss, whereby it reflects light at some angles, such as 20°, 60°, or 85° angles, and measures the intensity of that light. To measure surface sheen, the level of gloss is compared to standards that are calibrated and reported in units of gloss (GU).