Gloss is the property of a surface which involves specular reflection. Specular reflection is a sharply defined light beam resulting from reflection off a smooth, uniform surface. Gloss follows the law of reflection which states that when a ray of light reflects off a surface, the angle of incidence is equal to the angle of reflection.Reflection off smooth surfaces such as a mirror, an automobile, or a calm body of water leads to specular reflection. This reflection makes an object look glossy or shiny and is responsible for the lustrous or mirror-like appearance.
Semi gloss or low gloss
An object’s appearance is directly related to the geometric conditions, that is, the direction of the light source and observer. Take for instance glossy highlights of colored nonmetal objects. The nonmetal object will appear to have white highlights. One does not look at the highlights of the colored object to see color, but that is precisely where one looks to see and measure gloss.Semi gloss to low gloss is the property of a surface which involves reflection that is diffused rather than being purely specular. The diffused reflection from a rough surface is one in which a collimated input beam emerges in all directions, though in one direction, the specular direction maybe favored.