The lightness of equiluminance regions of a light source appears different due to distinct properties of surrounding surfaces (lightness induction). For example, for a bar-grating stimulus in relatively low spatial-frequency, the same gray bars are perceived lighter when they are flanked by black bars, compared to those flanked by white bars (lightness contrast; Helson, 1963). However, the dire...

In this paper, the effect of lightness on blackness preference of 216 black fabrics prepared by printing method is investigated. 18 observers including of 9 males and 9 females are asked to firstly rank order black fabrics with the same lightness values according to their preference. In the next step, observers are asked to define their blackness preference for blacks with different L values. R...

We have recently shown that eye movements have an effect on lightness estimation of real objects. Observers tended to fixate points with above-average luminance and they overestimated the objects’ lightness. The matched lightness was higher when observers were forced to fixate a bright region of the object than when they fixated a darker region. In the present work we performed a simulation wit...

We examined whether observers veridically perceive the reflectances of real objects under natural viewing conditions. A new forced-choice paradigm was used to measure observers' abilities to identify (not match) the reflectance of randomly crumpled gray papers across two levels of illumination, and also to simultaneously measure brightness discrimination thresholds for the same objects. Accurac...

When the transmittance of a filter on a bicolored background is varied, the lightness differences that vary are those between the filter and the background and that between the parts inside the filter. It is hypothesized that these are the differences of importance for the valuation of the apparent density of the transparent layer. The results of two experiments seem to show that the rated appa...

In a looking-time study, 24 infants 6 months of age were presented with continuously folding and unfolding patterns of stripes. The luminances in the dynamic lightness constancy pattern were changed in such way that adults attribute them to changes of the various regions' orientation relative to the light source (lightness constancy display). The "reversed" lightness constancy stimulus consiste...

This study develops a neuromorphic model of human lightness perception that is inspired by how the mammalian visual system is designed for this function. It is known that biological visual representations can adapt to a billion-fold change in luminance. How such a system determines absolute lightness under varying illumination conditions to generate a consistent interpretation of surface lightn...

Visual perception of object attributes such as surface lightness is crucial for successful interaction with the environment. How the visual system assigns lightness to image regions is not yet understood. It has been shown that the context in which a surface is embedded influences its perceived lightness, but whether that influence involves predominantly low-, mid-, or high-level visual mechani...

Variants of a lightness effect described by [Todorovic's, D. (1997). Lightness and junctions. Perception, 26, 379] were studied to quantify the failure of lightness constancy as a function of target luminance and target size. Todorovic's effect is similar to White's effect. Simultaneous lightness contrast appears to operate selectively between stimuli belonging to the same perceptual group, and...

We investigate the role of lightness perception in determining the perceived contrast of images. In particular, it is known that the background luminance of a display affects the relationship between onscreen luminance and perceived lightness. Stevens & Stevens (1963) modeled this effect using a simple power law. However, Whittle (1992) observed a more local effect, whereby subjects are more se...