Abstrakt:
This article presents a new series of measurements of printed samples on custom-made gonio-spectrophotometer and the respective evaluation by bidirectional reflectance distribution function. A set of three different papers (matt, glossy, and metallic) printed with six primary spot colours, together with Spectralon, were measured. Dependence of bidirectional reflectance distribution function on the reflection zenith angle, as well as its spectral representation, is presented. The results obtained are discussed regarding the ability of the custom-made setup to determine glossy and colour components of the studied set of samples. Three methods of calculation of reflectance for a fixed geometry are applied and the CIELAB colorimetric coordinates derived to compare with CIELAB values obtained by a commercially available spectrophotometer.