Printing Quality Control--Classification of Quality Parameters (2)

The function of the printed image information surface is to convey the information to be expressed in the print, which is usually contrasted with the background portion. The information plane may be a line image, or it may be a monochromatic halftone image and a multicolor halftone image. The images reproduced by the text and the urban manuscript belong to the line image, which transmits the image information through the shape and layout of the image information surface. . This kind of image usually has a high enough color intensity and no hierarchy, and it is generally expected that it contrasts with the background to form a clear contrast. On the image information surface, the quality parameters related to the non-information surface previously described are still applicable, but the shape and edge contrast of the image have special significance to the quality of the line image. The unique quality parameters of the line image are shown in Table 6-2.

The second method of transmitting information on prints is to use a mesh density level to produce images. Mesh prints should have a good "uniform mesh" characteristic and expected density distribution in order to achieve the desired effect of the image. The quality parameters that affect this printed image are listed in Table 6-3.

This kind of print can convey a large amount of information of a scene, object or person through the expression of details.

This type of image has a large amount of information, and even though the subjective impression is quickly passed to the observer, it is difficult to objectively evaluate the quality of the printed matter. The contents listed in Table 6-3 are very brief, and do not mistake it for easy evaluation.

The third method uses color changes to convey more information than the density level. This ability is obtained by overprinting several different colors of halftone images. Satisfactory printing colors can be obtained with trichromatic inks, the purpose of using black ink is just to get better quality. The quality parameters of this kind of printed matter are much more complex than those of the previous ones. Multi-colored halftone print quality parameters are roughly listed in Table 6-4. Such prints involve much more complex issues such as color balance.

These are merely rough outlines of the main parameters involved in evaluating the quality of printed matter. When specific tests and controls are implemented, more specific parameters and indicators are included under these parameters. Print quality analysis and other terms also face many interesting and complex issues.


Source: Certified Color