Abstract
We are surrounded by a variety of color distributions, which change greatly according to the surrounding environment. It is not yet well understood how much the appearance of objects is influenced by these color distributions in the surrounding environments. Brown and MacLeod (1997) showed that color appearance depends on the chromatic surround variance; this is known as the “gamut expansion effect.” However, Brown and MacLeod used relatively small patterns on a monitor. Whether the same effect would be obtained in an actual room environment has not been investigated. We examined whether the colorfulness perception of an object is influenced by the chromatic variance of its surroundings in a normal environment such as a room with furniture and objects inside. Two miniature rooms, one with gray and one with color-saturated objects inside, were placed side by side and used as a reference and a test room, respectively. Observers compared the colorfulness of a small square patch placed in the reference and the test rooms. The results showed that the apparent colorfulness of a patch was generally lower when it was closely surrounded by color-saturated surfaces, suggesting that the color appearance was changed slightly by the influence of other saturated objects in the room. However, the shift was very small, implying that chromatic surround variance has little influence on color appearance in an actual environment.
