Two experiments were performed to relate the Bezold-Brücke (B-B) and lightness compression effects. The first used a calibrated screen to present an achromatic luminance staircase. In addition, it reproduced, the methodology and the essential aspects the lightness compression effect discovered by Cataliotti and Gilchrist (1995). That is, observers perceived a truncated grey scale (from white to...

A novel extension to a previous method has been proposed to evaluate the nature of dry powder mixing processes using a mixing sensitive colouring agent. The method proposed measures the change in the colour (hue) and colour intensity of the powder blends over mixing time. To evaluate the extent of fine particle dispersion and de-agglomeration, cohesive and free flowing lactose (white) and cohes...

Using an asymmetric color matching technique, we measured the perceived changes that occur in the saturation and hue of colored stimuli at different eccentricities within the central 25 degrees of the human retina in nine color-normal subjects. A cone-opponent-based vector model was used to compute the activity of the L-M and S-(L+M) channels. The results show that a large proportion of the shi...

in this research, kiwifruits (hayward) were selected in two mass ranges (large and small). they were placed in one-liter glass bottles in the vicinity of the polyethylene sachets containing potassium permanganate nano-zeolite (0, 0.2, 0.4 and 0.8 g) and were stored in a germinator (5°c temperature and 30% relative humidity). then, the physicochemical properties of the fruits (soluble solid cont...

abstract this study was carried out in japan for evaluation of the relationship between phenolic compounds and skin color indices of 3 apples cultivars including ‘fuji’, ‘jonathan’ and ‘jonagold’, in 2006. in ‘jonathan’, l* (lightness) increased with decreasing red color of skin. in ‘jonagold’, chroma increased with increasing red color. but in ‘fuji’, there was no detectable difference between...

Hue matching was used to obtain measures of Bezold-Brucke hue shifts with very brief flashes (17 msec) at ten wavelengths and several illuminance levels. Results were generally similar to those obtained by Purdy (1931) with uncontrolled stimulus duration. but there were also important differences. These were: the locations of invariant hues; the direction of shift for blue-green hues: and a rev...

The HLS colour space is widely used in image analysis as it is physically intuitive. As the hue component of this space is defined on the unit circle, standard greyscale image analysis operators, specifically morphological operators, are not applicable to it. A variation of the standard morphological operators which require the choice of an origin are discussed. In addition, some lexicographica...