Significance and Use
The options available in methods for the measurement of color or color-difference are many. These involve choices in: (1) specimens, (2) geometric and spectral properties of instruments, (3) calibration bases for standards used, (4) procedure for sample handling including conditioning, (5) procedure for taking data, and (6) equations for converting instrumental data to final results. Once the measurements have been made, it is essential to document what has been done for the purpose of interlaboratory comparisons, or for future use. A sample form is provided in Fig. 1 to record identifying information applicable to any instrumental method of color or color-difference measurement.
Refer to Guide E179, Practices E991, E1164, E1345, E1708, E1767, E2152, and E2194 and Test Methods D5386, D6166, E1247, E1331, E1347, E1348, and E1349, for specific details of measurements.
|Metadata for Color or Color Difference Measurement of Specimens|
FIG. 1 Sample Report Form
1.1 This practice covers the documentation of instrumental measurement of color or color difference for current communication or for future reference. The practice is applicable to instrumental measurements of materials where color is seen by reflected, transmitted or emitted light and any combinations of one or more of these processes. The practice is recommended for documentation of methodology in interlaboratory color-measurement programs.
1.2 Providing an adequate identification of an instrumental measure of color or color-difference involves documenting the metadata necessary for archiving and future use of the measurement data collected. The metadata can be divided in five parts:
1.2.1 Nature and source of available samples and the form of specimens actually measured,
1.2.2 Instrumental conditions of measurement, including instrument geometrical and spectral conditions of measurement,
1.2.3 Standards used,
1.2.4 Data acquisition procedure, and
1.2.5 Color scales employed.
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 whoever uses this standard to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.
2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.
D156 Test Method for Saybolt Color of Petroleum Products (Saybolt Chromometer Method)
D1209 Test Method for Color of Clear Liquids (Platinum-Cobalt Scale)
D1500 Test Method for ASTM Color of Petroleum Products (ASTM Color Scale)
D1535 Practice for Specifying Color by the Munsell System
D1544 Test Method for Color of Transparent Liquids (Gardner Color Scale)
D2244 Practice for Calculation of Color Tolerances and Color Differences from Instrumentally Measured Color Coordinates
D5386 Test Method for Color of Liquids Using Tristimulus Colorimetry
D6166 Test Method for Color of Naval Stores and Related Products (Instrumental Determination of Gardner Color)
E179 Guide for Selection of Geometric Conditions for Measurement of Reflection and Transmission Properties of Materials
E259 Practice for Preparation of Pressed Powder White Reflectance Factor Transfer Standards for Hemispherical and Bi-Directional Geometries
E284 Terminology of Appearance
E308 Practice for Computing the Colors of Objects by Using the CIE System
E313 Practice for Calculating Yellowness and Whiteness Indices from Instrumentally Measured Color Coordinates
E991 Practice for Color Measurement of Fluorescent Specimens Using the One-Monochromator Method
E1164 Practice for Obtaining Spectrometric Data for Object-Color Evaluation
E1247 Practice for Detecting Fluorescence in Object-Color Specimens by Spectrophotometry
E1331 Test Method for Reflectance Factor and Color by Spectrophotometry Using Hemispherical Geometry
E1345 Practice for Reducing the Effect of Variability of Color Measurement by Use of Multiple Measurements
E1347 Test Method for Color and Color-Difference Measurement by Tristimulus Colorimetry
E1348 Test Method for Transmittance and Color by Spectrophotometry Using Hemispherical Geometry
E1349 Test Method for Reflectance Factor and Color by Spectrophotometry Using Bidirectional (45:0 or 0:45) Geometry
E1708 Practice for Electronic Interchange of Color and Appearance Data
E1767 Practice for Specifying the Geometries of Observation and Measurement to Characterize the Appearance of Materials
E2152 Practice for Computing the Colors of Fluorescent Objects from Bispectral Photometric Data
E2153 Practice for Obtaining Bispectral Photometric Data for Evaluation of Fluorescent Color
E2175 Practice for Specifying the Geometry of Multiangle Spectrophotometers
E2194 Practice for Multiangle Color Measurement of Metal Flake Pigmented Materials
E2729 Practice for Rectification of Spectrophotometric Bandpass Differences
Other Standard Documents
DIN6176 Farbmetrische, Bestimmung von Farbabstnde bie Krperfarben nach der DIN99-Formel Available from Beuth Verlag GmbH (DIN-Deutsches Institut fur Normung e.V.), Burggrafenstrasse 6, 10787, Berlin, Germany, http://www.en.din.de.
color; color difference; colorimetry; data format; documentation; instrumental measurement—color/light; metadata; reflectance and reflectivity; spectrophotometry; transmittance and reflectance;
ICS Number Code 17.180.20 (Colours and measurement of light)
ASTM International is a member of CrossRef.
Citing ASTM Standards
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