ISO 18314-1:2015 pdf free

ISO 18314-1:2015 pdf free.Analytical colorimetry – Practical colour measurement
For highly precise measurement results, the samples shall be plane. Dependent on sample size, multiple readings shall be taken. The individual measurements shall exclude trends and outlayers. The aperture size of the instrument shall be as large as possible.
For measurements taken on curved samples, the geometrical conditions specified for plane samples are no longer applicable. Measurement uncertainty and deviation of results from those of plane surfaces will increase as curvature increases. When selecting the measurement area on curved surfaces, the smallest possible curvature (biggest curvature radius) shall be placed on the smallest possible measuring aperture. To increase repeatability, the use of a customized sample holder is recommended.
Comparison of samples with different surface properties (e.g. texture, glos) may lead to different results depending on the measuring geometry of the instrument (see Clause 7).
The measurements shall be performed for the following conditions:
– Illuminant: D65 (for determination of metamerism additional illuminants are needed);
– Observer: 10°;
– Colour space: CIELAB or DIN 99
– Colour differences: It is important to take into consideration that CIELAB colour space is not visually uniform for small colour differences. Therefore, the use of the colour difference correction formula CIEDE2000 or the new colour space DIN 99 are recommended.
NOTE Standard iluminant D65 is defined in ISO 11664-2. Standard colourimetric observer for 10° is defined in ISO 11664-1. CIELAB is defined in ISO 11664-4. The DIN 99 formula is defined in DIN 6176. The CIEDE2000 formula is defined in ISO 11664-6.
A black calibration standard is a standard which has low to no reflectance (for example a black light trap). Black calibration is used to establish a known zero point for the instrument. The black or zero reflectance calibration shall be performed with the black standard supplied by the instrument manufacturer. A black calibration is always done together with a white calibration. Some instruments perform the black calibration internally, thus eliminating the need for separate black calibration.ISO 18314-1 pdf download.