1.1 The Natural Color System NCS) describes colors exactly as we see them, is easy to understand, logical, and simple to use. Any of the millions of colors that exist can be defined within the NCS system and given a precise notation. When a user understands the NCS notation, it is possible to judge the attributes of a color and communicate and check specifications and identify colors. The NCS notations describe the purely visual properties of the color and have nothing at all to do with the mixing of pigments or reflection curves and so forth. This practice introduces the Natural Color System, its terminology, and conversion to and from CIE tristiumulus values. 1.2 The system described in this practice includes all color percepts that appear to belong to the surface of a material, provided the surface is not perceived to be metallic or fluorescent. 1.3 The system does not include colors that appear to belong to translucent or luminescent objects (so-called volume colors and luminous colors) nor does it include other visual properties of the surface layer, such as gloss and texture. An NCS notation does not describe the physical or chemical properties of an object. 1.4 This practice also specifies the conditions for visual or instrumental determination of the NCS notation of a color sample and defines the relationships between psychometrically determined NCS notations and the corresponding CIE color coordinates that are to be used in this context. 1.5 For accuracy requirements for NCS standards and NCS color samples, the user is referred to Swedish Standard SS 01 91 04 (E)NCS colour samples Observation and measurement conditions and tolerances. 1.6 Units-The values stated in SI units are to be regarded as the standard. No other units of measurement are included in this standard. 1.7 Acknowledgement--ASTM International has obtained a license from the Scandinavian Colour Institute AB (SCI) to use the NCS System. NCS-Natural Colour System is a trademark of the SCI, Stockholm, Sweden and is protected by copyright (www.ncscolour.com). All rights reserved. Original NCS color samples are only available from SCI or any authorized NCS distributor. Any reproduction, copying, or commercial use of the samples or the NCS System without a licence from SCI is strictly forbidden. 1.8 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.
The NCS color system is gaining wider use throughout the world, especially in the specification of architectural color. Designers, paint manufacturers, and users of color all may use the NCS system.
Keywordscolor; natural color system
The title and scope are in draft form and are under development within this ASTM Committee.Back to Top