Based on "CTP - computer direct plate making technology" map production process (3)

3.2 The overall efficiency is greatly improved Because the map production process flow in the CTP computer-to-plate system is more simplified, intermediate processes such as film output and printing are reduced, output from the publication file is started, printing is started, and the traditional computer plate making process It takes about four hours, and the use of computer-to-plate, the process requires only 25 minutes (see Table 1). At the same time, in the production environment of the CTP process, human resources are saved and the overall efficiency is greatly improved.

3.3 Quality Improvement of Map Products The high quality and efficiency of the CTP process are clearly recognized in the industry. As the CTP technology eliminates the traditional process of film, printing, imposition, development and other technological processes, the error of human operation is maintained, and the quality of printed products is significantly improved. The general manager Zhang Xixun of Xi'an Coal Airline Map Printing and Printing Co., Ltd. once said that the CTP system can minimize the variable factors in the platemaking process, so that the quality of the printing plate can be best controlled, and enterprises can be encouraged to move toward digitalization and networking.

In the traditional process flow, the proof sample of the ink proofing is usually submitted to the map publishing management department for approval. After the approval, the map content is modified or modified by modifying the original map file and then outputting the soft version, or directly modifying the film for repairing the Yang. Completion, it is clear that the former method increases the cost of the business, and the latter modification comes at the expense of the quality of some maps. In the production process flow of the CTP map, the digital proofing sample book was used instead of the proof sample book of the ink proofing to send it for approval, successfully solving this flaw in the traditional map process flow.

The characteristics of the map publishing industry and the complexity of the content of the map product itself determine that the quality of the map printing process is difficult to control. The application of CTP process flow has undoubtedly become an effective way to improve the quality of map products. From the perspective of production practices, the work of large-scale atlases using the CTP process process reflects a high level of printing and printing. The “Atlas of the Sustainable Development of the Yangtze River Economic Zone” in the base was awarded the 2001 ICA International Cartographic Association’s excellent atlas. prize.

4. Based on the "CTP-computer-to-plate technology" map production process map printing process with the progress of hardware and software continues to evolve, can now be divided into the following four stages:

Map Design Determine map map data, map projections and scales, map contents, and presentation methods based on the purpose of the map. In addition to considering its contents, the data selection must also take into account digital methods and digitization preparations, such as determining the stratification and separation of elements; selecting mapping software and further research and development based on the purpose and characteristics of the map. Finally, the design book for the map is still written.

Data Entry This is the phase of data acquisition. The graphic image of the data is converted to numbers for storage, identification, and processing by the computer. Currently, there are basically two digitization methods used. The first method is digitization using the online tracking method, and the second method is automatic scanning. Both ways have their advantages and disadvantages. Since the data obtained by the two input methods can be converted to each other, the scanning method is receiving more and more attention. Graphical statistics can be entered directly into the computer using the keyboard. After digitizing the cartographic data, a database is created for computer processing and application.

Data Processing The process of computer graphics begins with the process of transforming graphics into numbers (digitization). Under the control of the database, the data is processed (the graphics are changed as required by the drawing), and the numbers are converted to graphics (graphics output). Data processing is at this stage between input and output, including data retrieval, updating, selection, transformation, etc. These tasks are all implemented by the mapping personnel calling the program.
Data output data output methods include screen display, drawing, optical system output film (CTF), output plate (CTP), and digital printing (Computer to Print/Paper). At present, map production is still printed (CTF or CTP) is the main data output method.

5 Problems that should be noted 5.1 CTP-based color map publishing systems still need to be combined with other graphic software or GIS software to design the CTP as a visual product. Its graphic symbolization and artistic expression are first class. The color map publishing system developed using the CTP computer-to-plate system should have the universal features and advantages that the electronic publishing system brings to map production. At the same time as the DTP-based color map publishing system, the quantitative description function is very important for map production. Limited, unable to complete the automatic positioning of symbols and charts, there is no topological relationship between the graphics, polygon formation awkward, so the color map publishing system based on CTP technology still need to be combined with other graphic software or GIS software mixed design.

5.2 Mistakes in Digital Proofing Applications

The key technologies for digital proofing include color management technology and RIP technology. At present, the digital proofing products of various manufacturers are basically the same as the standard printing results in color, and surpass the traditional proofing in terms of stability. However, many users do not believe this, so they continue to test with previous prints and documents, and then compare the similarities and differences between each other. In fact, this is a misunderstanding. In China, most printing companies are limited in the front-end proofing equipment, personnel, and technology, and the printed proofs themselves are not standard. Therefore, the printed products are far from the standard. That is, people's requirements for digital proofing color should be to maintain the same state stably and predictably. This state is a state in which the color can be guaranteed under strict process conditions.

5.3 The application of CTP technology should be fully integrated with the digital management of printing enterprises. The CTP technology must be combined with the digital management of the printing enterprises in order to make full use of the effectiveness of the computer-to-plate system. Although some printing enterprises have introduced CTP equipment and technologies, their utilization rate is not high, and modern data management methods cannot be applied to management. As a result, equipment idleness and waste of resources are caused. The introduction and application of CTP technology not only involves the technological innovation, but also brings the digital management concept to the printing and manufacturing enterprises. The cooperation mode between the CTP equipment and the supporting process forms an assembly line, which requires companies to digitally manage the printing process for real-time monitoring.