The principle of digital proofing
Digital proofing is an application system composed of digital color management software and professional color printers. At present, there are three main principles and implementations of digital proofing color management:
The first is the use of ICC private color matching theory and technology, using a spectrophotometer, through the color matching of printed proofs and print proofs to form an ICC Profile to manage and debug colors. He is the future direction of development, but at present, ICC technology is in the process of perfection. There are still many problems such as high capital requirements and complicated use of equipment under conditions of various domestic production conditions, limited funds, and low levels of personnel and management.
The second is the use of traditional color control theory, given the reflection density through the simulation of traditional proofing control methods, through the control of density and dot network to achieve color management, it is the basis for ICC method to control color management, is the traditional proofing to digital proofing transition Color management technology, but there are also problems with high theoretical and technical requirements for operators.
The third is the hybrid color management method that combines the first and second methods. For the actual situation of domestic printing production, a digital proofing system using a hybrid color management method is effective and easy to grasp.
At present, there are three types of software for digital proofing:
One is design proofing for layout design;
The second is color proofing for color effects (Colorproof);
The third is screen proofing for color and dot effect. One of the most widely used color proofing.
Digital proofing equipment
Inkjet printer
Inkjet printers use thermal foaming principles to eject ink through a nozzle onto a substrate to form an image. This proofing technology has high printing precision, strong color function, small size, light weight, and low price, and is widely used in the printing industry.
2. Sublimation printer
This proofing system uses a print head containing thousands of heating elements and a color strip containing CMYK colors for proofing. The print head produces 256 different levels of heat, which are solid pigments that sublimate into steam and condense on the receiver media. At the center of each point, the color is darker and the edges are lighter. When the printed four-color pigments fuse with each other, a continuous tone image is formed. The image printed by this printer has continuous colors and close to the output quality of the color photos. The color is very beautiful, but the cost is high and the number of prints is also slower, which is suitable for high-end users.
3. Thermal transfer type color printer
It uses the heating element on the print head to heat, so that the solid ink on the ribbon is transferred to the print media. This kind of printer has high printing quality, high speed, and the proofs are close to the printing effect, and it is easy to realize high-definition printing. The application is more extensive.
4. Color laser printer
Color laser printers are based on monochrome laser printers. It uses a laser beam to scan the light drum. By controlling the opening and closing of the laser beam, the photosensitive drum absorbs and does not absorb the toner. The photosensitive drum then transfers the absorbed toner to the paper to form a print image. The printing system has high precision, but the hue of the toner is not yet ideal, the color gamut is not wide enough, and the level of analog printing is limited.