G. Schouten et Fjj. Blommaert, BRIGHTNESS INDENTION - A NOVEL COMPRESSION MECHANISM IN THE LUMINANCEBRIGHTNESS MAPPING, Perception & psychophysics, 57(7), 1995, pp. 1023-1031
In a previous study, Schouten and Blommaert (1995) explicitly showed t
hat brightness constancy implies a substantial compression in the lumi
nance-brightness mapping. Here it is argued that additional compressio
n mechanisms are required for scenes with large luminance ranges, To t
race these, a series of experiments was conducted which involved expan
sion of the luminance range. We used a simple spatial configuration co
nsisting of a disk on a contourless homogeneous surround (Ganzfeld). T
he contrast between the disk and Ganzfeld acted as the independent var
iable, while the size of the disk was parametrically varied. Sequentia
l dichoptical brightness matches with a reference were carried out for
both the disk and the surround, The results reveal a compression mech
anism which we term brightness indention. This indention, which has no
t previously been reported in the literature, only occurs if the Ganzf
eld is less luminous than the disk, and it takes the form of a brightn
ess decrease of the immediate surroundings of the disk.