In today’commerce, instrument makers and instrument users must deal with a large array of bench-top and portable color-measuring instruments, many with different geometric and spectral characteristics. At the same time, manufacturers of colored goods are adopting quality management systems that require periodic verification of the performance of the instruments that are critical to the quality of the final product. The technology involved in optics and electro-optics has progressed greatly over the last decade. The result has been a generation of instruments that are both more affordable and higher in performance. What had been a tool for the research laboratory is now available to the retail point of sale, to manufacturing, to design and to corporate communications. New documentary standards have been published that encourage the use of colorimeters, spectrocolorimeters, and colorimetric spetrometers in applications previously dominated by visual expertise or by filter densitometers.⁸ Therefore, it is necessary to determine if an instrument is suitable to the application and to verify that an instrument or instruments are working within the required operating parameters.

This practice provides descriptions of some common instrumental parameters that relate to the way an instrument will contribute to the quality and consistency of the production of colored goods. It also describes some of the material standards required to assess the performance of a color-measuring instrument and suggests some tests and test reports to aid in verifying the performance of the instrument relative to its intended application.

1.1 This practice provides standard terms and procedures for describing and characterizing the performance of spectral and filter based instruments designed to measure and compute the colorimetric properties of materials and objects. It does not set the specifications but rather gives the format and process by which specifications can be determined, communicated and verified.

1.2 This practice does not describe methods that are generally applicable to visible-range spectroscopic instruments used for analytical chemistry (UV-VIS spectrophotometers). ASTM Committee E13 on Molecular Spectroscopy and Chromatography includes such procedures in standards under their jurisdiction.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.