Common and relative components of reflected light as information about the illumination, colour, and three-dimensional form of objects

Abstract.— A model for perceptual analysis of the proximal stimulus into common and residual components, earlier described in a series of papers by Johansson and his co-workers for motion and space perception, is applied to colour perception. Though still premature, this application seems to make colour constancy a natural result of the analysis in the same way as size and form constancy is solved by Johansson's vector analysis in the frame of reference of projective geometry. Applications of the model to Land's Mondrian experiments, to simultaneous contrast, and to the Cornsweet-OBrien effect are outlined. The information from variations and invariances in reflected light (besides the geometrical projection) is discussed with reference to Gibson's ecological optics.     

Chromatic induction as a function of luminance relations

Chromatic induction by red, green, and blue surround was studied as a function of surround/test field luminance ratio using a compensation method. Luminance ratios from 0.01 to 28.7 were used. The number of subjects was 8–10 in the three experiments. The results show maximum induction to appear at a luminance ratio around 1.0 when varying the test field luminance (Experiment 1) and at higher ratios when varying the surrounding luminance (Experiments 2 and 3). This difference is discussed in relation to the Kirschmann-Kinney controversy (Kirschmann, 1890; Kinney, 1962) and in relation to an earlier study using a magnitude estimation method (Bergström & Derefeldt, 1975).     

Effects of surround/test field luminance ratio on induced colour

Abstract.— According to Kirschmann's third law the induced colour is at its maximum when the inducing and induced fields are of equal luminance. Later studies (Kinney, 1962) show the induced colour to be most pronounced at a luminance ratio (inducing/induced) of about 4/1. In the present study the amount of colour induced into an achromatic test field was determined for one inducing colour, red, by letting observers judge the colour strength of the induced field. The test (or induced) field luminance was varied to give luminance ratios between 0.5/1 and 2/1. The results show that both colour strength and blackness increase as the luminance ratio is increased. The fact that the test field was judged even to have maximum chromatic colour strength and maximum blackness at the same time is discussed in relation to the method used and in relation to earlier studies on the "mode of appearance" of colours and the bidimensionality of achromatic colours.     

A theory of veridical space perception

Abstract.— A theory of veridical space perception based on the principles of movement parallax is proposed. Since optical changes are ambiguous with regard to veridical distances it is suggested that veridicality is obtained on the basis of an interaction between optical information and information from the body-state system. The optical system generates size and shape constancy on the basis of proximal common motions described by a vector-derivative model. The body-state system is thought to register information in a similar manner, and the interaction between the two subsystems is assumed to function according to the vector-derivative principle.     

Hue shift of induced colour as a function of luminance relations

The hue of induced colour was studied as a function of surround/test field luminance ratio using a chromatic surround and an achromatic central test field. The hue of the test field was determined by means of colour naming methods. Three inducing colours were used: blue (Wr No. 47), green (Wr No. 58), and red (Wr No. 25). The number of subjects was 9–11 in the two experiments. The luminance ratio (ranging from 0.07 to 17.1) was varied by varying the luminance of the test field (Experiment 1) or of the surround (Experiment 2). For the blue surround the results show a hue shift in accordance with the Bezold-Brücke phenomenon. For the inducing colours green and red the induced colours are weak, and the hue shifts are more or less unsystematic though there are individual subjects showing a trend in the Bezold-Brücke direction. It is concluded that the hue shifts depend on the luminance relations rather than on the test field luminance.