In simplest terms, brightness is the appearance of luminance and lightness is the appearance of objects. The experiments in this paper measure the appearance of three visible faces of a real cube in real-life illumination. Three faces of the cube are painted white and
the other three are painted different shades of gray. When the observer sees three white faces the experiment measures the appearance of illumination. When the experimenter rotates the cube to make visible a face with a different reflectance in the same illumination, then the experiment measures
the appearance of objects.The results of matching experiments show that humans make the same match for luminance changes caused by illumination as those caused by reflectance. Humans can successfully recognize changes in whites due to illumination. They mistakenly interpret reflectance
changes as illuminant position changes. However, in the same image they make the same matches for dark areas that were caused by illumination, reflectance or both.
Journal Title : Color and Imaging Conference
Publisher Name : Society of Imaging Science and Technology
Publisher Location : 7003 Kilworth Lane, Springfield, VA 22151, USA
In simplest terms, brightness is the appearance of luminance and lightness is the appearance of objects. The experiments in this paper measure the appearance of three visible faces of a real cube in real-life illumination. Three faces of the cube are painted white and
the other three are painted different shades of gray. When the observer sees three white faces the experiment measures the appearance of illumination. When the experimenter rotates the cube to make visible a face with a different reflectance in the same illumination, then the experiment measures
the appearance of objects.The results of matching experiments show that humans make the same match for luminance changes caused by illumination as those caused by reflectance. Humans can successfully recognize changes in whites due to illumination. They mistakenly interpret reflectance
changes as illuminant position changes. However, in the same image they make the same matches for dark areas that were caused by illumination, reflectance or both.