You have to go to Latin in order to find the etymological origin of the term contrast. Specifically, we can determine that this word comes from the sum of two different parts: the prefix with -, which can be translated as “together”, and the verb stare, which is equivalent to “stand up”.
According to digopaul, contrast is the action and effect of contrasting (showing opposite conditions or marked differences, checking the accuracy of something). The contrast, therefore, can be the opposition or opposition that exists between things or people.
For example: “The press detected a marked contrast in the attitudes of both candidates”, “It was impossible not to notice the contrast between the polished shoes of Dr. Castro and the worn sandals of his son”, “That house is not so pretty, but it is striking due to the contrast it produces with the buildings around it”.
That which stands out by opposition marks a contrast.
Contrast in journalism
Taking this meaning into account, we would have to determine that the term that concerns us now is used very frequently within the journalistic field. And it is that in order for a media professional to be able to offer truthful information subject to reality, it is necessary to contrast the data that he already has.
Thus, for example, when someone involved in an event gives you news, the logical thing is that you contact the other party involved to be able to contrast it. This is how he will get to know what is really going on.
When there is an obvious difference between light and dark in an image, there is a noticeable contrast.
Intensity difference in an image
It is common to use the concept of contrast to name the relative difference in intensity that exists between a point in an image and its surroundings. When the contrast is null, it is impossible to distinguish an object from its background. On the other hand, the higher the contrast, the easier it is for differentiation.
Contrast, in the visual aspect of an image, also refers to the scarcity of intermediate tones, so that light and dark stand out prominently. An image composed of white squares and black squares will show an obvious contrast; On the other hand, if the squares included different shades in a gray scale, the contrast would be non-existent.
The substance that is introduced into the body to make the organs observable by X-rays or other similar methods is known as contrast. Without this contrast, the image that the professional intends to analyze would not be visible.
Iodine and barium are the two elements that give shape to that substance that is introduced into the body of the patient in question in order to subject it to tests such as x-rays or magnetic resonances with which it will be possible to know what is happening to it. Thus, some results will be obtained, which will make it possible to discover what disease they are suffering from, the state of the pathology that has already been diagnosed, or what actions must be carried out in terms of treatment.
In cases of cancer, kidney problems or gastrointestinal diseases, it is when the use of contrast is usually resorted to.
Lastly, the hallmark is the brand that works as a guarantee for noble metal objects that have been hallmarked (that is, their authenticity has been verified).