1.1 This practice covers the instrumental measurement requirements, calibration procedures, and material standards needed for obtaining precise spectrophotometric data for computing the colors of objects. 1.2 This practice lists the parameters that must be specified when spectrophotometric measurements are required in specific methods, practices, or specifications. 1.3 Most sections of this practice apply to both spectrophotometers, which can produce spectral data as output, and spectrocolorimeters, which are similar in principle but can produce only colorimetric data as output. Exceptions to this applicability are noted. 1.4 This practice is general in scope rather than specific as to instrument or material. 1.5 This standard does not purport to address 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.