How to use the original correction function of the

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How to use the original correction function of the scanner to process pictures (I)

most operators only adjust the resolution and zoom ratio when using the scanner to scan images, and the rest use the default settings. Practice has proved that this can not obtain the best scanning effect. Especially when the original image is defective, the scanning result is even worse. When scanning defective images, how can we give full play to the best performance of the scanner and scan high-quality images? This requires careful analysis of the original, making full use of some original correction functions provided by the scanner, and carefully adjusting the preset values of the scanner

I. the brightness and contrast should be adjusted during scanning for the pictures with inaccurate exposure. The pictures with excessive exposure look white due to their high brightness; Underexposed pictures look dark due to low brightness. At the same time, the images are lack of levels and details. At this time, we can drag the slider on the brightness and contrast slider to make the image have moderate brightness and contrast. Since the adjustment of brightness and contrast is effective for all pixels in the image, care should be taken not to lose sight of one or the other. For example, the main information of an image is located in a darker area. Making it brighter can make the details more obvious. However, if you use the brightness adjustment function to lighten all areas, you will lose all details in the areas with higher brightness

II. Color balance should be adjusted during scanning for color biased pictures. If the image is somewhat color biased, the overall color tone of the image can be changed by using the color balance option. If the color deviation is not serious, you can select the automatic color balance option to let the software automatically correct; Manual adjustment shall be carried out in case of serious color deviation. The color of the scanner is mainly a mixture of red, green and blue. The scanner provides adjustment functions for these three basic colors. There are three sliding bars in the adjustment options: red, green and blue. To adjust the image color, simply drag the slider on the slider bar to the color you want to add to the image, or drag the slider away from the color you want to reduce. To adjust the color, you need to master some knowledge of chromatics, especially the principle of complementary colors: the two colors in relative positions on the color wheel are called a pair of complementary colors, such as red and cyan, green port a and port P conduction color and magenta, blue and yellow are complementary to each other. The so-called complementarity means that the reduction of a color in an image will inevitably lead to the increase of its complementary color. It is absolutely impossible for a color and its complementary color to increase or decrease at the same time

III. the gamma value shall be adjusted during scanning for pictures lacking levels. The gamma value affects the hue of the middle value of the graph or the gray level of the middle level. By adjusting the gamma value, we can change the brightness value of the gray scale of the middle tone of the image, so as to increase the middle level of the image, without much impact on the levels of the dark and bright parts. Entering a number larger than one will expand the range of the middle tone, which can make the image with a large proportion of the middle tone produce less contrast and more details. Entering a number smaller than one will narrow the range of the middle tone, which will increase the contrast of the image and reduce the details of the image. When the curve moves downward, the corresponding pixels of the image become dark; As you move up, the corresponding pixel lights up. Its adjustment often needs to be used in conjunction with the brightness and contrast increase that shall not exceed the specified limit to achieve satisfactory results

IV. pictures with poor composition

should be cut reasonably during scanning. Pictures with improper framing often have disordered backgrounds, unobtrusive themes or skewed scenery, resulting in poor visual effects. When scanning, you can select the scanning range to choose or reject the original image, correct the skewed image and re create the art. The specific operation is to select the scanning size as user-defined in the scanning setting option, and then select the area to be scanned by dragging the selection box in the preview image window. The method is as follows: hold down the left mouse button at one corner of the area to be scanned, drag the selection box to the opposite corner of the scanning area, and release the left button. In this way, the scanner will automatically scan only the selected area. For pictures with skewed scenery, just use the rotation function to correct them

v. the image to be printed

shall be scanned with the function of removing lines. In the printing field, the hanging printing technology is used, which relies on countless dots of different sizes to show the brightness of the image


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