With the development of printing technology and the improvement of people's living standards, the printing of newspapers has gradually moved from simple black and white printing to color printing, and it has a considerable scale. However, due to the uniqueness of color newspaper printing, such as newsprint whiteness, poor smoothness, lack of gloss, large ink absorption; manuscripts are mostly news photos, there is a phenomenon of color cast, characters and landscape is not clear; printing machine use volume Paper web presses, fast printing speeds, and so on, have caused more or less quality problems in color newspaper printing, such as color casts, lack of bright colors, poor resolution, and overprinting. There are many reasons for these quality problems. According to the printing characteristics of color newspapers, correctly processing the scanning and separation of different manuscripts is the most important step in improving the quality of color newspapers.
First, the basic requirements for scanning color separation
1. Bright and colorful. In order to reflect the propaganda effect of color newspapers and take into account the printability of color newspapers, it should be appropriate to make the colors pure and saturated. In Photoshop, we can increase the saturation and improve the basic color in spot color correction, and reduce the opposite color.
2. Strong contrast. The maximum density of newsprint printing is only about 1.2. The highlights of the paper have a background color of the paper. The deepest point is also thin due to the relationship between high-speed rotary printing. The operation can be properly compensated by the method of calibration and partial deflection. White field Department can give up part of the high light level, taking into account the background of the paper, the depths of the dark field at the various color version of the foot, four-color ink superimposed to reach more than 360%, and sometimes even can be deepened alone in the black version of the dark tone at the outlet value.
3. Emphasize clarity. High-speed printing often produces imaginary halos, resulting in subtle levels of loss. Therefore, when the mask is sharpened, it can be slightly overdone, the character manuscripts can be weak, and the scenery and buildings can be stronger.
4. Under color removal. In the color printing process, the bottom color can also be used to reduce the amount of ink, which facilitates quick overprinting of the rotary machine, which is beneficial to neutral gray balance and makes the layout clean and bright.
5. Since manuscripts are influenced by time, transmission, and many factors of the equipment, this requires the operator to have a certain aesthetic view, so that the overall color picture must not be distorted, the color should be close to its real effect, and the black and white fields of the picture should be set. The area with extremely high light can be netted, but large areas should not be netted, and dark areas should be preserved.
Second, deal with different manuscripts
Due to the needs of news sources, the types of manuscripts are relatively diverse. There are reversal films, negative films, general photographs, and printed materials (prints, magazines, posters, posters, etc.) from the media. From the subject matter, there are people and landscapes. , architecture, artwork, etc. The quality of manuscripts varies, and some of them are even color casts, and the levels are not adjusted. How to correctly handle different types of originals during scanning and separation should be an important aspect of color newspaper printing.
1. Negative film processing: Due to the different type of negative film, all kinds of film have unique color tone characteristics. This kind of deviation can be corrected by professional unloading equipment and processing methods in the unloading process, and direct scanning negative film is more difficult to restore correctly. Color space, so pay attention to the authenticity of color when using a negative as an original. The following methods can be used: 1 first scan with a roller scanner at a higher resolution into an RGB format; 2 invert processing in photoshop; 3 select the film background as a white field, and the darkest place as a black field; 4 pairs each The RGB color channel is adjusted appropriately, and finally the color picture can be processed according to the positive picture.
2. Secondary manuscript processing: The second manuscript is usually a printed matter or a sample. The biggest problem with printed manuscripts is that moire is prone to occur. When handling, the function of removing moire must be selected. DISPECKLE can be properly done in photoshop to better remove moiré, and sometimes changing the original placement angle can also get unexpected results. Try to use a higher resolution when scanning, it also helps to get a clearer image.
3. Telecommunications manuscripts and digital photos: This type of manuscript is mostly transmitted after compression, and the compression rate is high. During processing, excessive magnification cannot be performed, and the definition value of the resolution is also slightly smaller than the normal picture. From the aspect of the level, the level distribution is not uniform, and if the face is bright and the background is dark, the processing cannot be limited to a specific manuscript. The levels should be restored as far as possible so that it can be reproduced well.
4. Artworks such as Chinese paintings and oil paintings: The black edition is of utmost importance when printing traditional Chinese paintings. It is the skeleton of the works and has rich tone levels. It can increase the proportion of black editions in color separation, and can be used in background color removal. The black version of the heavy, the longer tone is dominated by black, CMY supplemented; the original manuscripts of oil paintings are removed with very little background color, so that the accumulation of ink reflects the thick sense, while the emphasis on sharpness is also done very well. less.
5. Photographs with severe color cast or loss of gradation: use scan and color separation parameters, use many of the gradation adjustments, high school low key scaling, gradation adjustments, spot color corrections, sharpness enhancements, and bottoms provided in Photoshop. Color removal, neutral gray balance, etc. are adjusted.
According to the large increase rate of printing dots in newsprint newsprint, for adjusting the original, adjusting the highlights and midtones of the image properly, the calibration curve is controlled to be a relatively concave curve so as to obtain better contrast; for the darker The original should adjust the dark and midtones of the image appropriately, and control the calibration curve to a relatively convex curve to increase the brightness and improve the dark details.
Third, neutral gray balance
Neutral ash imbalance can cause color cast. Since the hue and saturation of the ink have different degrees of color shift, the CMY mixing of the same amount of ink does not result in gray color. Therefore, the gray balance parameter should be used to adjust the color correction. In different areas, the reference data of the gray balance is as follows:
Highlight part
If the percentage of C's outlets is 3%-4%, the percentage of outlets of M and Y is O%-2%. If the percentage of outlets of C is 5%-7%, the percentage of outlets of M and Y is 3%.
-5%. Normally, M and Y are about 2% to 3% less than C. If C, M, and Y are the same, they are slightly warmed, but if M and Y are larger than C, they are considered to be Tinted gray.
2. Medium and dark tone
If the percentage of C's outlets is 15%-20%, the percentage of outlets of M and Y should be 5%-8% lower than that of C; if the percentage of outlets of C is 45%-65%, the percentage of outlets of M and Y should be C is 11%-13% less; if the percentage of outlets of C is greater than 65%, then the percentage of dots of M and Y should be 8%-10% lower than that of C.
Color separation processing should also pay attention to the black version of the treatment, the black version also plays an important role in the color printing, moderate processing of the black version of the formation and removal of the bottom color, to reduce the thickness of the ink layer in the printing process, speed up the ink drying , Controlling color casts helps a lot. The length of the black version is based on the original. The original is brighter and brighter. The black version should be shorter. The primary colors are used to fully reflect the rich and colorful effects. The darker originals and the black version are longer. The amount of under color removal should be more to achieve the purpose of using black to suppress dark tone to avoid color cast. At the same time, it is also easy to adapt to the requirement of high-speed four-color wet wet-dry printing and original dark tone level reproduction.
Fourth, perform the necessary sharpening
Sharpening can improve the edge blur in some areas to enhance the image sharpness. The correct sharpening emphasizes the picture more clearly. Excessive sharpening can cause rough and embossed. Different manuscripts and output sizes vary sharply, but the average manuscript output size is small, the sharpening intensity is slightly larger, and the output size is larger, so the sharpening intensity is small.
Fifth, the choice of screen line number
The higher the number of lines, the richer the level of performance. However, as far as color newspaper printing is concerned, it is not possible to blindly choose high-line printing, because newsprint has a rough surface, loose fibers, and strong ink-absorption. If you choose high-line printing, 2% of high-light spots cannot be printed, and at the same time, the amount of ink is also printed. Insufficient phenomenon makes the color of the image appear light and unobtrusive and lacks a strong sense of vividness. Therefore, the selection of the cable should be based on the characteristics of the color report. If you choose according to the type of picture, characters, arts, manuscripts, should be rich in layers, strong sense of three-dimensional, you can choose to use 100-120l / in the number of screen lines, for general manuscript optional 80-100l / in network cable number.
Sixth, concluding remarks
To improve the print quality of color newspapers, we must seize every step from scanning and color separation, plate making to printing. In scanning color separation, the parameters should be determined according to the characteristics of color newspaper newsprint printing in order to create favorable conditions for improving the quality of color newspapers.
First, the basic requirements for scanning color separation
1. Bright and colorful. In order to reflect the propaganda effect of color newspapers and take into account the printability of color newspapers, it should be appropriate to make the colors pure and saturated. In Photoshop, we can increase the saturation and improve the basic color in spot color correction, and reduce the opposite color.
2. Strong contrast. The maximum density of newsprint printing is only about 1.2. The highlights of the paper have a background color of the paper. The deepest point is also thin due to the relationship between high-speed rotary printing. The operation can be properly compensated by the method of calibration and partial deflection. White field Department can give up part of the high light level, taking into account the background of the paper, the depths of the dark field at the various color version of the foot, four-color ink superimposed to reach more than 360%, and sometimes even can be deepened alone in the black version of the dark tone at the outlet value.
3. Emphasize clarity. High-speed printing often produces imaginary halos, resulting in subtle levels of loss. Therefore, when the mask is sharpened, it can be slightly overdone, the character manuscripts can be weak, and the scenery and buildings can be stronger.
4. Under color removal. In the color printing process, the bottom color can also be used to reduce the amount of ink, which facilitates quick overprinting of the rotary machine, which is beneficial to neutral gray balance and makes the layout clean and bright.
5. Since manuscripts are influenced by time, transmission, and many factors of the equipment, this requires the operator to have a certain aesthetic view, so that the overall color picture must not be distorted, the color should be close to its real effect, and the black and white fields of the picture should be set. The area with extremely high light can be netted, but large areas should not be netted, and dark areas should be preserved.
Second, deal with different manuscripts
Due to the needs of news sources, the types of manuscripts are relatively diverse. There are reversal films, negative films, general photographs, and printed materials (prints, magazines, posters, posters, etc.) from the media. From the subject matter, there are people and landscapes. , architecture, artwork, etc. The quality of manuscripts varies, and some of them are even color casts, and the levels are not adjusted. How to correctly handle different types of originals during scanning and separation should be an important aspect of color newspaper printing.
1. Negative film processing: Due to the different type of negative film, all kinds of film have unique color tone characteristics. This kind of deviation can be corrected by professional unloading equipment and processing methods in the unloading process, and direct scanning negative film is more difficult to restore correctly. Color space, so pay attention to the authenticity of color when using a negative as an original. The following methods can be used: 1 first scan with a roller scanner at a higher resolution into an RGB format; 2 invert processing in photoshop; 3 select the film background as a white field, and the darkest place as a black field; 4 pairs each The RGB color channel is adjusted appropriately, and finally the color picture can be processed according to the positive picture.
2. Secondary manuscript processing: The second manuscript is usually a printed matter or a sample. The biggest problem with printed manuscripts is that moire is prone to occur. When handling, the function of removing moire must be selected. DISPECKLE can be properly done in photoshop to better remove moiré, and sometimes changing the original placement angle can also get unexpected results. Try to use a higher resolution when scanning, it also helps to get a clearer image.
3. Telecommunications manuscripts and digital photos: This type of manuscript is mostly transmitted after compression, and the compression rate is high. During processing, excessive magnification cannot be performed, and the definition value of the resolution is also slightly smaller than the normal picture. From the aspect of the level, the level distribution is not uniform, and if the face is bright and the background is dark, the processing cannot be limited to a specific manuscript. The levels should be restored as far as possible so that it can be reproduced well.
4. Artworks such as Chinese paintings and oil paintings: The black edition is of utmost importance when printing traditional Chinese paintings. It is the skeleton of the works and has rich tone levels. It can increase the proportion of black editions in color separation, and can be used in background color removal. The black version of the heavy, the longer tone is dominated by black, CMY supplemented; the original manuscripts of oil paintings are removed with very little background color, so that the accumulation of ink reflects the thick sense, while the emphasis on sharpness is also done very well. less.
5. Photographs with severe color cast or loss of gradation: use scan and color separation parameters, use many of the gradation adjustments, high school low key scaling, gradation adjustments, spot color corrections, sharpness enhancements, and bottoms provided in Photoshop. Color removal, neutral gray balance, etc. are adjusted.
According to the large increase rate of printing dots in newsprint newsprint, for adjusting the original, adjusting the highlights and midtones of the image properly, the calibration curve is controlled to be a relatively concave curve so as to obtain better contrast; for the darker The original should adjust the dark and midtones of the image appropriately, and control the calibration curve to a relatively convex curve to increase the brightness and improve the dark details.
Third, neutral gray balance
Neutral ash imbalance can cause color cast. Since the hue and saturation of the ink have different degrees of color shift, the CMY mixing of the same amount of ink does not result in gray color. Therefore, the gray balance parameter should be used to adjust the color correction. In different areas, the reference data of the gray balance is as follows:
Highlight part
If the percentage of C's outlets is 3%-4%, the percentage of outlets of M and Y is O%-2%. If the percentage of outlets of C is 5%-7%, the percentage of outlets of M and Y is 3%.
-5%. Normally, M and Y are about 2% to 3% less than C. If C, M, and Y are the same, they are slightly warmed, but if M and Y are larger than C, they are considered to be Tinted gray.
2. Medium and dark tone
If the percentage of C's outlets is 15%-20%, the percentage of outlets of M and Y should be 5%-8% lower than that of C; if the percentage of outlets of C is 45%-65%, the percentage of outlets of M and Y should be C is 11%-13% less; if the percentage of outlets of C is greater than 65%, then the percentage of dots of M and Y should be 8%-10% lower than that of C.
Color separation processing should also pay attention to the black version of the treatment, the black version also plays an important role in the color printing, moderate processing of the black version of the formation and removal of the bottom color, to reduce the thickness of the ink layer in the printing process, speed up the ink drying , Controlling color casts helps a lot. The length of the black version is based on the original. The original is brighter and brighter. The black version should be shorter. The primary colors are used to fully reflect the rich and colorful effects. The darker originals and the black version are longer. The amount of under color removal should be more to achieve the purpose of using black to suppress dark tone to avoid color cast. At the same time, it is also easy to adapt to the requirement of high-speed four-color wet wet-dry printing and original dark tone level reproduction.
Fourth, perform the necessary sharpening
Sharpening can improve the edge blur in some areas to enhance the image sharpness. The correct sharpening emphasizes the picture more clearly. Excessive sharpening can cause rough and embossed. Different manuscripts and output sizes vary sharply, but the average manuscript output size is small, the sharpening intensity is slightly larger, and the output size is larger, so the sharpening intensity is small.
Fifth, the choice of screen line number
The higher the number of lines, the richer the level of performance. However, as far as color newspaper printing is concerned, it is not possible to blindly choose high-line printing, because newsprint has a rough surface, loose fibers, and strong ink-absorption. If you choose high-line printing, 2% of high-light spots cannot be printed, and at the same time, the amount of ink is also printed. Insufficient phenomenon makes the color of the image appear light and unobtrusive and lacks a strong sense of vividness. Therefore, the selection of the cable should be based on the characteristics of the color report. If you choose according to the type of picture, characters, arts, manuscripts, should be rich in layers, strong sense of three-dimensional, you can choose to use 100-120l / in the number of screen lines, for general manuscript optional 80-100l / in network cable number.
Sixth, concluding remarks
To improve the print quality of color newspapers, we must seize every step from scanning and color separation, plate making to printing. In scanning color separation, the parameters should be determined according to the characteristics of color newspaper newsprint printing in order to create favorable conditions for improving the quality of color newspapers.
An ice cream bowl glass is a type of glassware specifically designed for serving ice cream. It typically has a wide and shallow bowl shape, allowing for easy scooping and enjoying of the ice cream. The glass is usually made of a durable material, such as tempered glass, to withstand the cold temperatures of the ice cream. Some ice cream bowl glasses may also have a stem or a foot to elevate the bowl and prevent it from melting the ice cream too quickly. Additionally, these glasses may have decorative patterns or designs to enhance the presentation of the ice cream. Overall, an ice cream bowl glass is a stylish and functional vessel for enjoying this delicious frozen treat.
Ice Cream Bowl Glass,Glass Sundae Dishes,Ice Cream Dishes Glass,Crystal Ice Cream Bowls
Xi'an ATO International Co., Ltd , https://www.xianato.com