Some new luminance-gradient effects

Three compelling luminance-gradient effects are described. The first effect concerns a brightness enhancement and a luminous mist spreading out from a central area having the same luminance as the white background and surroun ded by four rectangular inducers shaded with a linear luminance gradient. T he second effect is perceived with a photographically reversed configuratio n, and concerns what may be considered a brightness reduction or the enhanc ement of a darkness quality of a target area of the visual scene. The third effect concerns the perception of a self-luminous disk inside a somewhat f oggy medium. The effects are worthy of further examination because they cha llenge current theories of luminosity perception and brightness perception in general.