Prepress issues summary (1)

Although the desktop publishing technology has undergone earth-shaking changes, it has brought more and more advantages to the processing of graphic and text information, and the output work of the output center has also been continuously improved, but some things have not changed: that is, the customer brings output. The file always has problems such as "the lack of fonts in the file", "image resolution error", "order error page settings" and so on. Problems like this often occur at the output center, using the wrong font in the page, or the image disappearing, or the file can't be printed at all, which not only wastes time but also wastes money. Faced with these problems, what our prepress production staff should do.

In digital processes everywhere today, prepress staff must take on the work done by electronic color separation personnel in the past, or they must at least understand the principle of electronic color separation, which can prevent the creation of a document that may have problems in the next process. . If the prepress creator knows what to watch out for, then preventing output errors will become easier. In order to make the print production staff no longer make the same mistakes, and to find out how to avoid mistakes, I think the following aspects are worth noting.

First, problems caused by lack of experience

New generation publishers of image software that has just used Windows are often inexperienced. The problem with Windows files for newbies is far greater than the Mac problem. However, prepress production staff and output centers still have to compete with these familiar issues because novices will experience the mistakes that old employees have already experienced.

Another condition that makes the output center difficult is the increasing use of color inkjet printers. Prior to color inkjet printing, many designers mistakenly relied on black and white laser printers to verify the final output; after color inkjet printers were applied, confusion became more serious. Because many customers only admit their own (color inkjet) proofs, even some people rejected Matchprint proofs, because the colors can not meet the color inkjet proofs they bring. Because inkjet printers can print color gamuts that are wider than four-color prints, the colors of inkjets look more vibrant or saturated than the final four-color prints.

Similarly, web design experience has changed the expectations of many prepress creators for print. Like inkjet printers, computer monitors are less sensitive to differences in resolution and can display more colors than offset printing. Prepress producers see a variety of pictures on web pages that they would like to apply to print. The result is the placement of a GIF image. After the file of such a web page image is exported to the film, the printing result is conceivable.

Second, the font: still the number one error

Each prepress creator's most commentary on the designer's mistake is the font. Since the advent of electronic publishing, designers have forgotten to deliver the necessary fonts. But the mistake is far more than losing the font: designers often send wrong fonts, or changed fonts, or incompatible fonts due to version differences. For example, some advertisers occasionally use Macromedia Fontographer software to make font changes. Although they send new modified fonts, ATMs often cannot recognize it as a valid font file. At this time you need to do font replacement, sometimes only to replace other fonts. For advertisers, the modified font is mostly a headline word, so in the illustration software, the headline word should be set. It is better to convert the font into a path at design time, and then put the word into the spring and autumn typesetting software. Become a vector file, the font file is no longer needed.

This method also solves another frequent problem: the fonts placed in the EPS format file are lost. Because it is easy to forget the font of the text in the placed image when placing the image into the layout software, especially when other people create the image. Turning the font into a path ensures that the document can be printed correctly. Of course, converting to a path can slightly distort complex fonts. Of course, in order to avoid this phenomenon, your only choice is to choose to include fonts.

Even if the designer sent the font, some people still make mistakes. For example, users of Mac machines often send screen display fonts instead of printer fonts. Once the file is opened, the computer often does not report font errors; after the results are printed, the font is dot-matrix rather than smooth.

In the Windows-based desktop publishing system, the problem that often arises is that the font used by the designer in the file is a TrueType word, but the Type1 font is transmitted, or the font used is a word, but what is transmitted is TrueType fonts. On the monitor, the fonts look the same, but the text is reversed because TrueType and Type1 fonts use different kerning and font width tables.

For designers using a Mac machine, fonts from Adobe or other major vendors are mainly used. These font output centers are generally available. Therefore, there are few errors in the output of these types of files. However, for the PC, the variety of fonts used, and the output center can not be all purchased for backup, therefore, when the output of such documents, there are more errors in the font, and special attention should be paid to the font in the design.

When designing a file, some people download all the fonts in the file instead of just downloading the fonts that are needed to print the file. Such a file also has some problems in the output. For example, when CorelDraw software is installed, the program installs hundreds of fonts in the font directory. When the font menu is displayed, it becomes difficult to match the fonts on the disk with the font names.

To avoid font problems, the best solution is to use PageMaker's Prepare for Service Bureau or QuakXPress's Collect for Output widget. PageMaker's widget will collect the fonts used in the file and tell which of these fonts are TrueType words and which are Type 1 words. The XPress plugin will create a font table for the fonts used in the file.

Third, the headache picture

Following the font problem, the biggest problem with the output center is the picture. Some people estimate that the output center will make more or less corrections to the pictures in all files sent before the output file, which has become a routine task for the center.

The most obvious problem is that customers often do not include pictures in files. The customer can put the linked picture in the typesetting software, but when sent to the output center, he forgets to send the picture placed in the file to the output center together. Therefore, when the output, it is not reported that the picture is wrong, that is to get a Low resolution pictures. Sometimes customers do not link pictures at all. For example, documents produced by financial companies, the pictures in these files are often copied from Microsoft PowerPoint or Excel to a file, when the layout file contains only one WMF file. When the picture is processed in the output, it is not the line width error, which is the color cast.

So, recreate the illustration in Adobe Illustrator or some other suitable illustration software. Do not put it into Illustrator by grabbing or cutting and scraping. The best way to do this is to hook it first and then export it as an EPS file. Put into Illustrator.

The WMF file is not the only file format that cannot be interpreted by Postscript RIP. In addition, LZW compressed TIFF format files, especially when the format of the image in the publishing software has been indented, RIP interpretation problems. Because RIP must first decompress the image and rescale the image at the new size, the file will always be printed or not printed at all. Therefore, images must be stored in uncompressed CMYK TIFF or EPS format.

Some problems should be paid special attention when using the QuarkXPress layout software. Because XPress can easily rotate, mirror, invert, etc., the production staff often does not do the processing of the image in Photoshop. All this work is handed over to Xpress software, which means that RIP must also do the appropriate processing. Inverted, rotated, and mirrored images have a large amount of work for RIP and cause serious crashes. Therefore, if the image is to be rotated, mirrored, inverted, etc., it is best to do these tasks in Photoshop and then put it into place.

When the file is finalized, unnecessary paths created in Photoshop must be deleted. Because if you leave unnecessary paths in the image, RIP is awkward.

With the popularity of web pages, the output center has encountered more and more problems when processing pictures. Many customers often put files in the 72dpi GIF format RGB index images they downloaded from the Internet. This kind of image looks good on the screen, and the ink-jet printing effect is also good, but these images often cannot be separated. Even if they were converted to CMYK TIFF images, the resolution was not enough. If you reduce the image to improve the resolution, the quality of the output may not be acceptable. Although reducing the size of the image can help increase the resolution, it can affect the color and sharpness of the image.

On the other hand, some customers increase the resolution of the image in Photoshop. This is only forced to increase the pixels of the image. These pixels do not exist in the original image, and the interpolated pixel is only at the cost of reducing the contrast of the image. The only way to guarantee a high-quality image is to scan or acquire the image in the final output size and resolution.

Fourth, different color types can not be mixed

Another problem that causes output headaches is that designers break the rules when defining colors in files and placed images: mixing spot colors, CMYK, and RGB colors in the same image or file. For example, they use spot colors and RGB colors to create Illstrator graphics, then place this picture into QuarkXPress, and define four-color separations.

Even if the designer defines colors consistently, the problem still occurs when the same color has a different name. For example, Illustrator and XPress have slightly different naming conventions for Pantone spot colors. So the designer puts Illustrator's picture into XPress. When using the same Pantone color to create another object, once separated, it will be expressed in two different colors. Similarly, CorelDraw sometimes separates whites as spot colors (usually in gradients).

The solution is to rename or redefine the color. In the first case, change the Pantone color name in XPress; in the second case, use CorelDraw's Paper color instead of white.

Five, 12 output preparation points

The following are 12 output preparation points that will help designers prepare output files for smooth output.

1. Set the file so that the page size of the electronic file matches the page size of the print.
2. Unless the font is very complicated or finely detailed, turn any text in the EPS file into a path before you enter it into the layout software. 3. Scans or acquires images as much as possible at the final output size and at the appropriate resolution (bigger or better).
4. Rotate, mirror, or invert the image in the software that created the image, rather than in the typesetting software.
5. Remove extra paths and channels before storing the last picture to simplify the file.
6. If the image is to be color-separated, the color is defined using the CMYK mode, and if it is not, it is defined as a spot color.
7. Store pictures in uncompressed TIFF or EPS format.
8. Print test separations on a laser printer to ensure that you don't have extra separations or unwanted spot colors.
9. Use QuarkXPress Collect for Output or Adobe PageMaker's Prepare for Service Bureau widget to ensure that you know which fonts are included and send the fonts along with your files to the output center.
10. Leave traps and layouts to the output center unless you have previously discussed and reached a tacit agreement.
11. When sending a file to the output center, please