Several Requirements for Designers in Printing Graphic Design

The graphic design can be divided into a printing type graphic design and a non-print type graphic design based on the carrier whose final work is completed. Print graphic design has the highest proportion in graphic design work. The scope and content of the design are the most extensive. The books, newspapers, magazines, pictures, bills, bills, etc. that we usually contact are produced through design and printing processing. . Printing is a complex technology. In addition to having a deep knowledge of fine arts, it is necessary to fully understand the printing process and some related knowledge in order to make a manuscript that meets the requirements of the printing process. In fact, some of the works designed by graphic designers usually do not achieve the desired results after printing. The reason is that designers do not understand the printing process and do not understand the latest printing technology. The author hereby discusses some requirements for printed graphic designers from the perspective of printing with his own practical teaching and learning experience.

About color

　　 1 Use CMYK's printing color scale (color card) to control the color of the work

Most printed graphic designs today use computers for design and production. The computer's display is colored with R (red), G (green), and B (blue) light. The primary colors are colored by the color light additive method, and the color gamut is large. The printing color is produced by C (blue) and M (product). The four color materials Y, Y (yellow), and K (black) are color-reduced by the colorant and have a small color gamut. It can be seen that the color rendering of computers is different from the printing color rendering principle and the color gamut is different. The final output goal of printing graphic design production is to print four colors of C, M, Y, and K. Therefore, the designer should define, adjust, and control the color in the process of designing the printing color. Only then, the color of the work. The appearance will be guaranteed.

In terms of specific operations, if it is a color continuous tone image (such as pictures taken from the computer or designers to collect photographs, etc.) how to ensure the restoration of its color?

1 scanning color correction and optimization of the level of input into the computer, from RGB packet mode to CMYK color mode, this is a color separation process, the color separation parameters to meet the printing system equipment characteristics, directly using the color separation parameters of the printing points Colored files can be used for output.

2 In the CMYK color space, the CMYK values ​​of some key colors in the image (such as skin color, blue sky, etc.) are corrected to ensure color reproduction during printing. Of course, the key color adjustment can not be based on the screen color, should be based on the corresponding color on the printed color chart, it is best to remember the common key color C, M, Y, K color values, and the image The corresponding color is adjusted to this color value. To accurately correct key colors, it is best to keep familiar with the common colors you see and their CMYK color values.

3 If you are coloring graphics and text, in order to have an accurate color appearance when printing, you must select the desired color in the printed color chart, and use the corresponding CMYK color value combination to set the graphic object. So no matter what color appearance is displayed on the screen or how complex the output and printing process are, the color appearance of these graphics and texts has a basic guarantee. The color effect of the final printed matter is determined by the ratio of the CMYK components, and on the screen. Seen colors have nothing to do, the screen color is only a code of CMYK combination color.

The coloration of the print is very complex, and the same set of CMYK color values ​​will vary depending on the paper, ink, printing equipment, printing control parameters, and the printer. So is this CMYK printing color chart to control the color is accurate and reliable? Don't worry, because skilled output center printers can reasonably estimate the influence of different conditions on color and make appropriate adjustments, generally ensuring that the color error is within 10%, which is generally acceptable in the domestic market.

The choice of 2 primary colors and spot colors

The primary colors mentioned here refer to C, M, Y, K and their overprinting colors, also called process colors; spot colors refer to specific color inks that are pre-mixed before printing, such as pearl blue, fluorescent yellow, etc. CMYK superimposed colors. Is CMYK four-color or spot color printing used for design? We discuss this issue in the following three aspects.

1 Under normal circumstances, we try to use primary colors, to avoid the use of spot colors, there are two reasons: First, four-color printing can be combined to produce most of the arbitrary colors, so as to give designers the greatest freedom of design; Second, spot color Ink is mostly imported ink, and the price is high. When printing, it is necessary to make a special printing plate. A single unit can take the paper once to complete the color printing, which will greatly increase the printing cost. However, if it is a simple spot color printing, such as the red headline of newspapers, the cost is lower than the cost of four-color printing.

2 Many well-known company's logo colors use specific colors and must be printed with spot colors. For example, the red color used on the logo of Coca-Cola is a spot color. Special ink must be used for special edition printing. Other unusual color effects, such as fluorescent yellow, pearl blue, etc., also require spot color inks for spot color printing to achieve results.

3 complex designs often require the use of spot colors and primary colors to complete the printing and copying. For example, if some printing needs to add the company's spot color logo to the effect of four-color printing, one or two spot color printing must be added. The cost is quite high.