contrast

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Related to positive contrast: negative contrast

contrast

1. (in painting) the effect of the juxtaposition of different colours, tones, etc.
2. 
a. (of a photographic emulsion) the degree of density measured against exposure used
b. the extent to which adjacent areas of an optical image, esp on a television screen or in a photographic negative or print, differ in brightness
3. Psychol the phenomenon that when two different but related stimuli are presented close together in space and/or time they are perceived as being more different than they really are

Contrast

A juxtaposition of dissimilar elements to show the differences of form or color, or to set in opposition in order to emphasize the differences.

Contrast

 

in psychology, the subjective exaggeration of the differences between perceived objects or between certain sectors of the visual field during their spatial (simultaneous contrast) or temporal (successive contrast) contiguity. Thus, when the color black is placed next to white it seems even blacker. Contrast may also be manifested in color change. For example, a gray square on a red background seems greenish blue; on a blue background it looks orange. The sharpest contrast of two colors is expressed at the boundary of the two areas (boundary contrast). The phenomenon of assimilation is the opposite of contrast. Contrast is widely used in various forms of art and literature.

REFERENCES

Vudvorts, R. Eksperimental’naia psikhologiia. Moscow, 1950.
Teplov, B. M. “Vzaimodeistvie odnovremennykh svetovykh oschchushchenii.” In Zritel’nye oshchushcheniia i vospriiatiia. Moscow-Leningrad, 1935.

contrast

[′kän‚trast]
(communications)
The degree of difference in tone between the lightest and darkest areas in a television or facsimile picture.
(computer science)
In optical character recognition, the difference in color, reflectance, or shading between two areas of a surface, for example,a character and its background.

contrast

The white level of a display screen. The contrast adjusts how bright the white is. See brightness and contrast ratio.
References in periodicals archive ?
The purpose of the first experimental condition, extinction, was to determine whether a decrease in the rate of reinforcement in the varied component resulted in increases in responding in the target components (i.e., positive contrast).
Gradient echo acquisition for superparamagnetic particles with positive contrast (GRASP): sequence characterization in embrane and glass superparamagnetic iron oxide phantoms at 1.5T and 3T.
The retrograde positive contrast urethrocystography revealed the morphology of the urogenital apparatus in specimens.
Australian Dollar's Strength Hinges on GDP and RBA Decision Fundamental Outlook for Australian Dollar: Bullish - First quarter capital investment and construction activity hint at a deeper contraction in 1Q GDP - Leading Index indicators point to a positive turn in growth beginning in March - Questions over US and New Zealand sovereign debt ratings put Australia in a positive contrast It is no stretch to say that risk appetite has ushered the Australian dollar to eight month highs against the its US counterpart.
The cat's owners got lots of pictures--from imaging techniques that included survey radiography, compression radiography, ultrasonography and positive contrast upper GI radiography.
However, if the original task is difficult, and the second task is easy, there should be positive contrast between the originally difficult task and the later easy task.
If intussusception is in the differential considerations, then the enema should be performed with appropriate technique for an anticipated reduction, whether with air or with positive contrast. If the abdominal radiograph is nonspecific, high obstruction or gastroesophageal reflux could still explain the symptom profile, making a UGI in order--with the caveat that ultrasound is a more specific test for hypertrophic pyloric stenosis.
Increased blood supply to the bowel wall can't be distinguished from a positive contrast agent, as both appear white on a scan.
HyCoSy, performed transvaginally without the need for anesthesia, assesses tubal patency using negative and positive contrast.
Rudi Bixtorf, fund manager for Coutts Bank Switzerland, said: "Overall it is a solid performance and a positive contrast to Unilever.
The Swiss have modified lighting techniques to provide vertical illuminance, which allows pedestrians in crosswalks to be seen in positive contrast. The result has been a lowering of fatalities by two-thirds.