SURFACE GLOSS TESTINGWMG offers Surface Gloss Testing services. Measured gloss ratings by ASTM D523 are obtained by comparing the specular reflectance from the specimen to that from a black glass standard. Since specular reflectance depends also on the surface refractive index of the specimen, the measured gloss ratings change as the surface refractive index changes. In obtaining the visual gloss ratings, however, it is customary to compare the specular refractive indices.
Since the instrumental ratings are affected more than the visual ratings by changes in surface refractive index, non-agreement between visual and instrumental gloss ratings can occur when high gloss specimen surfaces differing in refractive index are compared.
Reference: ASTM D523 Standard Test Method for Specular Gloss
Gloss Testing Services check Gloss, Haze, and Reflectance. Gloss & Reflectance can be measured at 20, 60 & 85 Degrees.