Colour is not a subjective impression in industrial processes, but a measurable quality feature. Uniform colour values are a prerequisite for stable processes, reliable approvals and cross-site comparability. This is exactly where it is decided whether colour measurement creates safety or becomes a source of error.
Consistent colour scheme is therefore a central quality factor in industrial applications. Whether plastic parts, paintwork or technical components – even small colour deviations can lead to rejects, rework or complaints. Reliable colour measurement therefore requires more than precise measurement technology: a clear methodology, controlled framework conditions and a uniform understanding of the measurement process are decisive.
In practice, it happens again and again that identical samples at different devices or locations lead to different measurement results. What is considered within tolerance in the laboratory is critically evaluated in production or vice versa. Such deviations create uncertainty, delay releases and make cooperation between departments and locations difficult.
The readings are not correct? Why it is frustrationed QM in the laboratory in front of laptop in the analysis of color measurement errors.
The problem: Why colour measurements differ from each other
The impression often arises that a measuring device delivers incorrect results. In fact, the causes of colour measurement errors in most cases are not in the measurement technology itself, but in varying measurement conditions, different settings or lack of standardization. Colour measurement is always an interplay of device, application and process.
A common error is to consider colour readings as absolute and unchanging. However, in industrial applications, this assumption is not practicable.
Typical causes of colour measurement errors
Absolute colour values are metrologically valid, but can only be reproduced to a limited extent in practice. The reasons for this are manifold:
- Light sources differ spectrally and influence both visual perception and measurement result.
- Surface structures such as matt or glossy reflect light differently.
- Different measurement geometries, measuring openings or sample positioning lead to systematic differences.
- Calibration state, device condition and operator influence play a central role.
- Umgebungsbedingungen wie Fremdlicht, Temperatur oder Verschmutzung wirken zusätzlich auf das Messergebnis ein.
Für industrielle Anwendungen ist daher nicht der isolierte absolute Farbwert entscheidend, sondern die Vergleichbarkeit mit einer definierten Referenz.
This way you can avoid colour measurement errors
The practical approach in quality assurance is the relative colour measurement. Colours are not evaluated in isolation, but are always compared with a previously defined reference. It is decisive whether the colour deviation (∆E, i.e. Delta E)) is within the defined tolerance limits.
This approach ensures that colour parts remain visually consistent within a production – even with unavoidable fluctuations in the process and environment.
Technically, this means:
- uniform measurement geometries and measurement parameters
- regular calibration and device matching
- normalized color standards for reference
- clear separation between approval measurements and process-accompanying measurements
Organizationally, clearly defined measurement instructions and standardized processes are crucial to keep measurement results comparable.
Best Practices for Reproducible Colour Measurement
In practice, the following measures have proven successful:
- Regular calibration
Only correctly calibrated devices provide reliable results. Certified references and fixed maintenance intervals prevent systematic deviations. - Standardized measurement conditions
Constant sample positioning, controlled lighting and defined measuring devices reduce the influence of extraneous light and handling errors. - Reference-based assessment
Measurement results are only meaningful when compared with stable, standardized color standards. - Simple and intuitive operation
Measuring instruments with clear menu navigation and self-explanatory operating logic minimize operator errors and increase reproducibility – especially in the production environment. - Transparent colour communication
Cloud-based software solutions enable cross-site access to color standards, measurement data and assessments. In this way, measurement results are communicated in a comprehensible, comparable and consistent manner.
Frequently asked questions (FAQ)
Why do measurement deviations occur between devices or locations?
Different measurement methods, calibrations, types of light or operating modes often lead to deviations.
Does absolute colour measurement make sense in the industry?
For quality assurance, the relative color measurement is decisive compared to a defined reference.
What is the role of the operation of the measuring instrument?
A big one. Intuitive operation reduces sources of error and ensures reproducible results.
How can measurement results be compared across locations?
Through uniform measurement methods, central references and transparent data systems.
Conclusion
Colour measurement errors are not an exceptional case, but a typical challenge of modern quality control. It is crucial to understand color measurement as a holistic process. Uniform methods, simple operation, regular device adjustment and transparent color communication create the basis for reproducible and reliable measurement results – regardless of device, location or user.
Training and practical support by ColorLite
In addition to suitable measurement technology, sound user knowledge is a key success factor. ColorLite therefore supports companies with practice-oriented training on color measurement.
Our trainings teach:
- Basics of colour metrics and colour tone management
- Safe and damage-free handling of measuring instruments
- Calibration and correct measurement
- practical exercises for measurement, evaluation and interpretation
In combination with intuitive measuring systems and cloud-based software solutions for cross-site color communication, this creates a sustainable approach to avoid color measurement errors.
