Prepare PDF files for a print provider
Open Prepress Interface (OPI) lets you use low-resolution images as placeholders for the high-resolution images that appear in your final work. When a print provider receives your file, the OPI server substitutes the low-resolution images with the high-resolution images.
Printers’ marks provide information to the print provider about how the work should be printed. You can specify which printers’ marks to include on the page. The available printers’ marks are as follows:
•
Crop marks — represent the size of the paper and appear at the corners of the page. You can add crop marks to use as guides in trimming the paper. If your output has multiple pages per sheet (for example, two rows by two columns), you can add the crop marks on the outside edge of the page so that all crop marks are removed after the cropping process, or you can choose to add crop marks around each row and column. A
bleed determines how far an image can extend beyond the crop marks. A bleed requires that the paper you are printing on is larger than the size of paper you ultimately want, and the image area must extend beyond the edge of the final paper size.
•
Registration marks — are required to line up the film, analog proofs, or print plates on a color press. Registration marks print on each sheet of a color separation.
•
Densitometer scale — is a series of gray boxes ranging from light to dark. These boxes are required to test the density of
halftone images. You can position the densitometer scale anywhere on the page. You can also customize the levels of gray that appear in each of the seven squares on the densitometer scale.
•
File information — can be printed, including the
color profile; name, date, and time the image was created; and page number.
To maintain OPI links in a PDF file
1
Click
File 
Publish to PDF.
2
Locate the folder in which you want to save the file.
3
Type a filename in the
File name box.
The
PDF settings dialog box appears.
5
Click the
Prepress tab.
6
Enable the
Maintain OPI links check box.
Don’t use OPI links if you are not sure whether your PDF file is destined for an OPI server.
To include printers’ marks in a PDF file
1
Click
File Publish to PDF.
2
Locate the folder in which you want to save the file.
3
Type a filename in the
File name box.
The
PDF settings dialog box appears.
5
Click the
Prepress tab.
6
Enable any of the following check boxes:
If you want to include a
bleed, enable the
Bleed limit check box, and type a bleed amount in the corresponding box.
Usually, a bleed amount of 0.125 to 0.25 inch is sufficient. Any object extending beyond this amount uses space needlessly and may cause problems when you print multiple pages with bleeds on a single sheet of paper.