In color reproduction, the angle difference between the plates is usually 0°, 15°, 45°, and 75°. Since yellow is a weak color and the visual effect is not strong when printed on a white substrate, the yellow plate is usually screened at a 15° difference, and the most important colors in the magenta, cyan, and black colors are arranged at 45°. .
In addition to arranging the angle difference, each color version must also consider the angle problem with the screen. Although the mesh/line has a matching relationship, the screen should still avoid the above angles. A simple empirical practice is that the screen angle is fixed at ± (4° to 9°), which is effective for reducing the screen moiré. .
The screen angle can be set using the following methods: diagonal stretch and oblique printing.
Oblique stretch net is in the process of stretching the mesh wire mesh direction and the frame into ± 9 °, taking into account the stretch direction must be vertical and parallel to the edge of the mesh frame, you can first use a large net frame stretch, How to nest a small net box after stretching the net.
Precautions when designing and outputting disc prepress
July 20, 2006 17:20
[HC Network Special Printing Industry Channel] 1. The EPS file is placed in other software. If there is zoom-in or zoom-out and rotation, do not save the DCS color separation format, otherwise the connection is not on the map.
2. When the EPS file is placed in other software, if it is placed, the EPS file will not be exported. Otherwise, a mosaic will be produced.
3, FreeHand can not be placed in the grayscale EPS map, otherwise all versions have the same network and angle
4, EPS in PageMaker can not be painted, otherwise the screen will not see and the film will change color
5, FreeHand IIIustrator text or lines if imprinting, must be defined before placing other software, or can not control its imprint.
6. After FreeHand text-to-path is set to fill or borderline imprinting, followed by another text-to-text path, FreeHand will automatically set its fill or edge imprint.
7, FreeHand document typesetting, such as the file in the file after the change in the graphics must be re-placed, otherwise the output changes.
8, FreeHand English mixed into paragraphs when the text is missing.
9. Don't align text and lines in placed graphics and layout files, especially EPS.
10, using Quark's trap function in the four-color images for trapping, must be based on different file images for different processing.
11, CoerlDraw when using the filling tool, for special effects fill must be under the conditions of color correction to see, and under its conditions issued.
12. EPS images cannot be saved in JPEG format.
13, in the IIIustrator file to ask whether it is issued by the version of the heart or by physical distribution.
14, Quark imposition must use the customer's file to fight, so that the same preferences.
15, FreeHand in the same text block in the two-color words easy to run.
16, PageMaker placed slender Tif map will only half.
17. The left hand side of the cropped graph is sometimes sent in FreeHand.
18. Large Tif maps must be stored in LZW format.
19, CorelDraw best without PSD through the bottom map, otherwise easy to come out white lines.
20, Xinhan instrument issued by the PC input word easily out of order.
21, old and new Chinese instruments can not be mixed.
22. PageMaker of PC can run vertically.
23, PC PageMaker English words can not be rotated.
24. When the Wits client generates PS, the gradation must be greater than 256 (including 256), otherwise the gradient has obvious steps, and the output RIP setting does not work.
25, Wits put photos files made by Photoshop to generate PS file, you can not change the picture information in Photoshop, if you change must be re-typed to generate PS file, otherwise the picture will be deformed.
Source: China Washing & Dyeing Industry Information Center
