Several mainstream color management systems compete in the prepress field
Adobe's Photoshop color management system as Adobe's most famous image processing software, Photoshop has its irreplaceable position in image processing. At the same time, Adobe also strives to develop Photoshop into a complete color management system. The color management feature of Photoshop software is controlled by monitor setup, printing inks setup and color separation settings
in order to make the color seen by the user on the screen as close as possible to the color of the output sample, the user's system must be calibrated first. The accurate color workflow must start from the display calibration and display settings. Monitor setup includes two parts: display calibration and display setup. In the display, the correct selection is made according to the display type, phosphor powder, color temperature, etc., so that when the image is converted into color mode, the correct color conversion can be carried out according to the settings of the above parameters
the basic purpose of printing ink setting is that Photoshop provides information about the ink, paper and printing machinery used for final printing. Different paper has different absorption and dot enlargement of ink, different ink has different color rendering, and different printing methods have different dot enlargement rates. Therefore, these parameters need to be set in the printing inks setup. After obtaining the basic information from the RGB image data and the display data obtained in the monitor setup, the color mode conversion can be completed according to the characteristics of the final printing conditions
the most important item in color separation is the determination of the amount of black plate. Theoretically, color separation from one RGB value can produce multiple CMYK values, and the final printing effect should be the same. However, due to the ink receiving capacity of different printing papers and the characteristics of different printing machines, it may not be possible in theory. Therefore, it is necessary to set the type of color separation, the amount of black plates, and the percentage of total printing points accordingly
apple's colorsync color management system colorsync is a color management system released by apple. It adopts ICC standards and takes Lab color space as the standard reference space. It is a system level color management software applied under the Mac operating system. It is an open color management system. Users can convert colors between different color management systems through the plug in module of colorsync. Colorsync system consists of three components, an ICC Standard color rendering 2, active description file, color matching method (CMM) and application software interface (API)
the device description file defines the color characteristic information of the device, through which the color range that the device can display, capture and reproduce can be obtained. When using colorsync to create a file, a profile file will be stored in the file. In this way, when processing the image with the YNC description file required by colors in the gas spring experiment of various models on other devices, colorsync will conduct color space matching operation by comparing the device characteristics of the image and the characteristics of the display, so as to obtain the best color. It can be summarized as four parts: color effect
color matching method is the core part of colorsync, which realizes the conversion of different color spaces. More importantly, colorsync's color conversion mode adopts the high-quality color matching technology of Linotype hell, so users can use a better color gamut compression method to deal with colors outside the color gamut
due to the different expressive power of various application software on color, the same image color will have different appearance from image scanning to final replication. In order to master accurate colors at all times in work, it is necessary to carry out effective color matching of these application software. Color matching can be carried out through the application software of colorsync, so as to achieve the same purpose
Kodak's color management system Kodak is a color management system that supports both PC and MAC platforms. Unlike apple colorsync and Adobe's Photoshop, Kodak's color management system tends to use a modular approach to color management, and provides several local modules, which can be combined to form a complete color management system. And it has the function of color management for Photo CD image input process, no matter for architecture
Kodak color management system generally includes kpcms, DCP, PICC and PCS100 modules, which can be used separately or combined into a complete color management system
kpcms module (Kodak precision color management system) provides enough device description files in accordance with ICC Standard format. Its input devices include RGB image sources and CMYK image sources, and its output devices include printers and proofing machines. However, it has great limitations because it cannot describe the device itself
dcp module (device color description file startup software package) is a software package designed to provide display and output color correction for photocd images. When opening photocd images, users are required to select two device description files. The input device description file is a description file of a photo CD device, and the output device description file can be a display description file or a color proofer description file. PICC module (precise input color characterization) provides a scanner utility standard program to enhance the function of DCP
for advanced image processing and scanning applications, Kodak provides PCS100 module to accelerate the color conversion process of photo CD and prophoto CD images. Using PCS100 module, direct links between various devices can be generated to skip the intermediate conversion process to CIE color space, saving time for each conversion and color loss in the conversion process