Distinctness of Image measures the sharpness of a reflected image in a coating surface. Similar coatings may have identical gloss values but visually the quality may be very different. A visually poor coating may have a highly textured dimpled appearance known as "orange peel". When a reflected object is viewed in such a coating the image becomes fuzzy and distorted.
In some conditions traditional gloss meters quantify visibly different surfaces with the same gloss value. When these surfaces are measured using a DOI gauge, an accurate fingerprint of the surface is generated. DOI identifies the effect of gloss, haze, polishing marks and orange peel on a coating.