In order to investigate the development of temporal contrast sensitivity functions (tCSFs) for chromatic (red/green) stimuli, we obtained chromatic contrast thresholds from 3-month-old infants and adults using behavioral techniques. Stimuli were moving or counterphase-reversing sinusoidal gratings of 0.25 c/deg. Five temporal frequencies were used: 0.7, 2.1, 5.6, 11 and 17 Hz (corresponding spe...

Three experiments were conducted to investigate the effects of adults aging upon the legibility of simulated symbol highway signs. Each experiment employed a different set of lighting conditions: (1) daytime luminance, (2) nighttime luminance, and (3) nighttime luminance with glare. Young (ages 18-25) and middle-aged (ages 40-55) observers demonstrated small reductions in legibility when lumina...

Gratings that contain luminance and chromatic components of different spatial frequencies were used to study the segregation of signals in luminance and chromatic pathways. Psychophysical detection and discrimination thresholds to these compound gratings, with luminance and chromatic components of the one either half or double the spatial frequency of the other, were measured in human observers...

A look-up table algorithm is described for enhancing the luminance resolution at the expense of the colour resolution in digital displays of colour images. For colour displays with a look-up table resolution of 8 bits/gun, the algorithm provides a luminance resolution of 11-12 bits without loss of spatial or temporal resolution. This improvement can reduce the minimum luminance step in the mid-...

Observers usually cannot discriminate the relative depth of a crowded feature with respect to crowding features about 2 arc min distant if all the features have the same luminance. However, stereo thresholds significantly less than 20 arc sec are obtained when the crowded feature is about twice as luminant as the features crowding it. The thresholds depend only upon the ratio of the luminance o...

To perform a more complete diagnosis on the effect of color vision deficiency on visual performance we measured luminance and color contrast threshold functions. Measurements were carried out on CRT for a range of spatial frequencies on color deficient and normal color vision individuals. Luminance and color contrast threshold is a measure of the recognition limits of low luminance and color co...

A considerable amount of research over the last decades has focused on the apparent specialization of V2 thin stripes for the processing of color in diurnal primates. However, because V2 thin stripes are functionally heterogeneous in that they consist of largely separate color- and luminance-preferring domains and because the color-preferring domains contain a systematic representation of hue, ...

Under dim background conditions, the S-cones make little or no contribution to luminance (A. Eisner & D. I. MacLeod, 1980; W. Verdon & A. J. Adams, 1987), yet under conditions of intense long-wavelength adaptation, a small but robust contribution to luminance--as defined by heterochromatic flicker photometry (A. Stockman, D. I. MacLeod, & D. D. DePriest, 1987, 1991) or motion (J. Lee & C. F. St...

Metacontrast (reduction in brightness of a test gash by the subsequent presentation of a spatially-adjacent masking flash) is abolished if the test and mask flashes are changed in hue with no luminance transients. To obtain metaeontrast. the masking flash need only be a luminance transient of as little as 0.05 log unit. Metacontrast refers to the brightness reduction of a test flash that occurs...

This study compared direction discrimination of cyclopean (stereoscopic) and luminance motion involving stimuli equated for effective strength. The stimuli were random-walk cinematogram (RWC) displays whose signal and noise discs were created from binocular disparity differences embedded in a dynamic random-dot stereogram or from luminance differences. Experiment 1 measured global motion detect...