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The main factors of printing color distortion and the identification method
Release time:
2023-07-18
Printing usually uses C, M, Y]]]]], K four-color ink to copy colors, and the image information collected by digital acquisition equipment to the computer is usually R, G, B information
KanThe main factors that cause color distortion.
1. Color distortion caused by color reduction treatment
Modern printing usually uses C, M, Y, K four-color ink to reproduce colors. Due to the purity problem of the ink itself, color distortion will also occur when printing.
2, color separation caused by color distortion
Printing usually uses C, M, Y]]]]] and K four-color ink to copy colors, while the image information collected by digital acquisition equipment to the computer is usually R, G and B information, so the image information needs to be converted into C, M, Y and K modes before printing and plate making, that is, color separation processing. The so-called "color separation" is to decompose and convert the color information (usually R, G, B color information) of each pixel of the image into color information suitable for printing C, M, Y, K modes. The color information is lost during the color separation process. In color separation, only according to the printing suitability of ink, paper, etc., the correct setting of color separation parameters (such as setting dot expansion value, gray balance parameters, black plate tone, etc.), it is possible to output high-quality color separation, as far as possible to reduce the loss of color information.
3, the original there is color distortion.
Printed images are mostly obtained by photographic means. For the original photo, in addition to the color distortion caused by improper operation in the shooting process, because the color is reproduced by coloring materials such as coloring materials, and the coloring materials are prone to color attenuation, which may also cause distortion of the color of the photo. In addition, with the continuous popularization of digital cameras, digital image originals are more and more, and the technical requirements of digital cameras for operators are greatly improved. Due to the poor technical level of operators, the captured images are prone to problems such as dim images and blurred images, resulting in color distortion of the originals.
4. Color distortion caused by scanning
The image density of the original photo is continuous, and the image information needs to be collected into the computer. When scanning an image with a scanning device, it is necessary to divide the image into discontinuous pixels, and collect the R, G, and B information of each pixel on the original point by point. In the scanning process, it will cause the loss of pixel color information, and image processing is based on the collected image information, and all operations on color are also carried out on this basis, and can not increase the color information of the image. Therefore, for photo originals, scanning is a very critical part of image processing, and improper operation will cause image color distortion.
How to identify color distortion
After understanding the main factors of color distortion, how to find color distortion in the actual production process is the key.
1, an impression of the benchmark method.
People's eyes have a certain adaptability to color. For images with slightly distorted colors, repeated observation will weaken the ability to recognize. Therefore, when judging whether there is color distortion, it is an important method to find color distortion by using the impression of one eye to eliminate the limitation of human eye color vision.
The neutral color reference method
There are many neutral colors in life, such as black, white, gray, etc. They are the zero point of color in the colorful world, and we can use them as the base point for distinguishing color distortion.
3, skin color benchmark method.
The color of the skin is familiar to people, and all images of people, especially those based on portraits, can be used as the basis for distinguishing color distortion according to the color of the skin. No matter yellow skin, white skin or black skin, its skin color has a rule, that is, it is blood color. That is, there is red in yellow, red in white or red in black. If the skin color of the figure in the image is yellow, it will give people a morbid feeling. Under normal circumstances, even if the color of the skin of the person in the image is really yellow, it should be adjusted to blood color during color correction, that is, there is red in yellow.
JINJIANG MODERN COLOR PRINTING CO., LTD.
Mobile phone: +86-13805950005 Mr.Ding
Address of the new factory: No.24, Dagong Mountain Road, Printing Base, Cizhao Town, Jinjiang City, Fujian Province
Address of the old factory: 1610 Shoe Capital Road, Chen Dai Town, Jinjiang City, Fujian Province
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