How Do I Get Consistent and Accurate Measurements?

Accurate color measurements are essential in any professional environment where color quality is decisive for technology, production, or aesthetics. Yet things often go wrong — not because the instrument is bad, but because the measurement conditions, procedures, and operator skills are insufficiently standardized.

The following guidelines form the basis for consistent, reproducible, and technically correct color measurements.

1. Always Calibrate Before Use

A colorimeter or spectrophotometer must be regularly calibrated to a known reference. Without calibration, drift occurs, which can lead to differences of several ΔE units.

• Follow exactly the manufacturer's maintenance and calibration instructions.
• Use clean, undamaged reference standards.
• Document the calibration moment in your QC process.

2. Use a Controlled and Standardized Light Environment

Light determines how color appears. Therefore, always assess or measure:

• Under D65 (daylight), and when necessary
• Under additional light sources such as A, TL84, or LED.

A light booth or standardized viewing room prevents variation and prevents metamerism-related deviations.

3. Correct and Consistent Sample Preparation

Ensure:

• A clean surface, free from dust and contamination;
• A uniform application (for coatings or print);
• Consistent substrate material;
• Flat placement without gloss disturbance.

Sample preparation is one of the most underestimated factors in color measurement.

4. Measure a Representative Area

Do not measure too small (noise), but also not too large (unwanted variation). Choose a measurement aperture that fits:

• The texture,
• The homogeneity,
• The type of material (coatings, plastics, powders, textiles).

5. Always Position the Instrument Identically

Use where possible a sample holder, template, or fixed positioning. Variation in angle, pressure, or orientation directly affects the result.

6. Perform Multiple Measurements and Take the Average

A single measurement tells little. Multiple measurements provide insight into:

• Variability of the sample,
• Stability of the instrument,
• Operator consistency.

The average provides the most reliable assessment.

7. Work as Much as Possible with Spectral Data

Spectral reflectance curves give a complete picture of color behavior. They are essential for:

• Root-cause analysis,
• Detection of metamerism,
• Pigment deviations,
• Material and gloss inconsistencies.

Colorimetric values (L*, a*, b*) are derivatives — useful but more limited.

8. Check the Correct Instrument Settings

Pay attention to:

• Observer angle 2° or 10°,
• Chosen illuminant,
• Gloss-in or gloss-out (for d/8 geometry),
• Measurement geometry (45/0 or d/8).

Deviating settings almost always lead to deviating ΔE values.

9. Record and Manage Environmental Conditions

Temperature, humidity, light, and even vibrations affect color measurements. Document these data — especially in quality discussions or product comparisons.

10. Work with Color Standards and Tolerance Agreements

Without a clear reference, any measurement is debatable. Therefore, always work with:

• Certified color standards,
• Established ΔE tolerances (e.g., CMC, ΔE2000),
• Agreed measurement conditions within the chain.

11. Keep Instrument and Software Up-to-Date

Software updates often contain improved color models, bug fixes, and new features. Instrument maintenance prevents drift, wear marks, and optical contamination.

12. Train Operators and Secure Skills

Measurement errors rarely arise from the instrument — usually from the operator.

Training should at minimum cover:

• Correct placement,
• Correct environment,
• Interpretation of spectral and colorimetric data,
• Recognizing error sources such as gloss, texture, and metamerism.

13. Validate Regularly via Independent References

Periodically measure a certified reference standard or have samples checked by an external laboratory. This ensures reliability and traceability.

Conclusion

Consistent and accurate color measurements are not accidental. They arise through standardized procedures, technical knowledge, instrumental discipline, and qualified operators.

With the right approach, any organization can perform color measurements that are reproducible, defensible, and professional — within and outside the chain.

Would You Like to Further Develop in Professional Color Measurement?

In the Applied Color Technology course, you will learn:

• Working with spectrophotometers,
• Setting correct measurement conditions,
• Interpreting tolerances,
• Practical cases from industry and quality control.

👉 View the course at: https://kleurenschool.nl

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Questions about color measurement or quality control? Contact the specialists at the Netherlands Color Institute: https://kleurinstituut.nl/contact