An easy to use hand-held reflectometer for measurement of the opacity, or luminous reflectance, of a grey scale. Suitable for the evaluation of a coatings’ hiding power, or simple shade sorting tasks of metallised films, anodized aluminium or ceramics.
 
The Opac Opacity Reflectometer (310) measures the diffusely reflected light from the test surface. The controlled conditions of illumination and angle of illumination allow surfaces to be characterised according to their lightness or darkness. A completely black surface will read a (zero), whilst a perfect white will be 100 units, recognised in colour measurement scale as the ‘Y’ value.
 
The Opac Opacity Reflectometer (310) can be used for comparison of contrast ratios (hiding power) of paints. The procedure involves applying the test sample onto black and white card or onto polyester sheets which is then placed over black and white glass plates.
Readings are taken on the coating over the black portion followed by a reading taken over the white portion.