Any PDF file you provide to ONAC will be printed by more than one newspaper, and each will process the file with different equipment and methods. The goal of the setup and method recommended here is to produce PDF files that perform reliably under the widest range of conditions and uses.
Our recommendation is simple: create PDF files by (1) printing to the AdobePS printer from the original application, which writes a Postscript file to disk; and (2) using the Acrobat Distiller to convert that Postscript file into a PDF file.
Once set up and configured, this approach has proven to give the most consistent, trouble-free, automatable results for all Acrobat versions, all types of ads, and all operating systems.
Acrobat software has been developed to serve many purposes, but in this document we are discussing its use for creating newspaper advertising in PDF format for distribution to multiple newspapers over the Internet.
Acrobat vs. Reader
In order to create PDF files, or to export EPS images of PDF files that can be placed in a page layout program, you must purchase and install the full Acrobat application. This is not the same as the free Acrobat Reader program, which can be downloaded from the Adobe Systems web site. The Acrobat Reader only allows viewing and printing of PDF files.
PDF files are compatible with both Macintosh and Windows computers. The only issue that causes problems between the two operating systems is that of TrueType fonts. TrueType fonts are native to Windows computers only and are rarely found on Macintosh computers. Postscript Type 1 fonts are compatible with both Macintosh and Windows computers, so Type 1 is the format in which fonts should be embedded in PDF files. On Windows computers, embedding fonts in Type 1 format requires the use of the AdobePS printer, installed and configured as described here.
At the time of this writing, Adobe Systems has released versions 3, 4, and 5 of Acrobat. Each has unique characteristics, but it is possible, with no loss of quality, to create PDF files with Acrobat 4 and 5 that are compatible with Acrobat 3. We recommend that you do so unless there is a compelling reason to do otherwise. The Acrobat Distiller settings given below for all versions are designed to produce PDFs that are compatible with all versions.
PDF editing and font embedding
One major new feature in Acrobat 5 is greater freedom to edit the text in PDF files. This comes at a price, however. Fonts are normally embedded in PDF files as "subsets": that is, font information in the original PDF file only applies to the characters that are actually used in the document. This drastically reduces the size of PDF files that contain text in many different typestyles.
If, in Acrobat 5, you edit the text in a PDF file, the current font assigned to that text (or one which Acrobat sees as similar) will be COMPLETELY embedded before the editing actually takes place. If you are editing the PDF on a Windows computer, the font will be embedded in TrueType format, even if the original font was embedded in the PDF file as a subset in Type 1 format.
Thus, font embedding (including font format) can change completely when you edit even a single character in a PDF file. For this reason, we recommmend that you make any necessary changes in the original document and then recreate the PDF file. This will ensure that fonts are embedded only as subsets and in Type 1 format.
Bundled PDF utilities
Because Acrobat is so universally used as an output format for page layout programs, newer versions of such programs as PageMaker, Quark Xpress, and InDesign automatically install some version of the Acrobat Distiller. This is usually integrated with an export utility designed to create a PDF file directly from any document.
These automatic, "bundled" installations vary widely. In some cases, if you install a new version of Acrobat, the export utility in your page layout program may still be using its own automatically installed version for creating PDF files.
For this and other reasons, we recommend that you avoid using the automatic PDF export utility in your page layout program, and instead install a full version of Acrobat. This will allow you to install and use the AdobePS printer, which is the most reliable way to create error-free PDF files.
Why use AdobePS printer?
TrueType fonts (Windows)
Because Windows primarily uses TrueType fonts, Windows users are especially advised to use this method of writing a file to disk for distilling into a PDF. Some page layout programs allow you to save individual pages as EPS files, and because Acrobat Distiller can distill EPS files, it is tempting to use this method as a shortcut. In Windows, however, TrueType fonts will be either be embedded in TrueType format (especially with Distiller 5) or not at all.
An EPS (Encapsulated PostScript) file is a special type of Postscript image file that is intended to be embedded in a larger Postscript layout. Therefore, on both Macintosh and Windows systems, an EPS file does not contain information about the page on which it was created, so you must go into the Job Options area and set the default page size to match the size of each EPS image you distill.
You can print to the AdobePS printer from any application you use (graphics program, page layout, word processor, spreadsheet) and distill the resulting file into a PDF. Other methods of creating PDF files from those applications, if available, tend to produce unpredictable results. Feel free to send us a sample PDF file if you wish to test some method other than the AdobePS print method.
Installing the AdobePS printer
Each version of Acrobat automatically installs three main elements: (1) Acrobat (Acrobat Exchange in version 3), which reads, prints, and exports EPS images from PDF files; (2) the Acrobat Distiller, which creates PDF files from the Postscript output of the AdobePS printer; and (3) the browser plug-ins, which allow you to read and print PDF files directly from the Internet rather than copying them to your hard disk and then opening them in Acrobat.
In most situations, the AdobePS printer is not installed automatically, and you will need to install it manually after Acrobat is installed.
The AdobePS printer is installed from the Acrobat CD and can be found in a folder under "Drivers" or "Utilities" (depending on your operating system and the Acrobat version). The folder, or the installer or setup file, is usually named with a version number, such as AdobePS 4.8.13. When you run it, it installs a new printer on your computer.
Many Macintosh computers include some version of the AdobePS printer which serves as the driver for laser printers attached to the system or the network. If you see AdobePS in the Chooser, you may think that the AdobePS printer is already installed. However, you will need a second instance of AdobePS to set up for creating PDF files.
To determine whether you need to install AdobePS on a Macintosh system, click on AdobePS in the Chooser. If it displays a list of the printers you normally use, you will need to install another AdobePS printer. If it displays as a "Virtual printer", click "Setup" and make sure that the PPD associated with it is that for Acrobat Distiller. If not, you will need to install another AdobePS printer from the Acrobat CD and associate it with the Acrobat Distiller PPD, which will be offered during the installation. It should be installed as a "local" printer that prints to a file on disk (that is, as a "virtual" printer) rather than to a printer port.
To see whether you already have the AdobePS printer on your system, click Start > Settings > Printers. If any printer is named "Acrobat Distiller" or something similar, you already have the AdobePS printer on your system, and you need only check its configuration as described here.
NOTE: If you have an Acrobat Distiller printer on your system but you did not install it yourself, it may have been installed automatically by your page layout program. If so, changing its configuration may alter or disable the automatic PDF export utility in the page layout program.
To avoid this, you can install a new AdobePS printer from the Acrobat CD and name it differently. (Any number can be installed without conflict, as long as they are named differently.) This would then be the printer you configure as described below.
The AdobePS (Acrobat Distiller) printer should be installed as a "local" printer that prints to a file on disk rather than to a printer port, and it should be associated with the Acrobat Distiller PPD. These options will be offered during the installation.
The instructions included here apply, with some variations, to all versions of the Windows operating system. Screen shots were created on a Windows 98 computer, and settings may appear in different places or with different names in later versions (Windows 2000, ME, and XP).
The most important feature of the AdobePS printer (also called the Acrobat Distiller printer) is that, configured as described below, it converts TrueType fonts to Type 1 format for embedding in PDF files. This conversion MUST be done if PDF files are to be used on Macintosh systems, and the majority of newspapers use Macintosh computers for graphics, page layout, and imagesetting.
Click here for instructions and screenshots on configuring the AdobePS printer in Windows.
Because PDF files are used for so many purposes, the settings for a newly installed Acrobat Distiller are not suitable for newspaper advertising. These settings can be changed easily, and (in Acrobat 4 and 5) different combinations of settings can be saved with descriptive filenames so that they can be reloaded later for specific purposes.
To use the Acrobat Distiller, you must first create a file on disk by printing to the AdobePS printer. Then you open the Distiller, open the file created by the AdobePS printer, and save it as a PDF file. This process can be automated, as described *here*.
The most critical settings in the Acrobat Distiller are the Job Options. These tell the Distiller whether and how to embed fonts, how to compress text and images, and how to deal with color. The default, out-of-the-box settings are not suitable for this use of Acrobat and should be changed as described below.
To change the job options, first start the Acrobat Distiller. When it is ready, choose "Job Options" from the Settings menu (Acrobat 4 and 5) or Distiller menu (Acrobat 3).
The descriptions in the following sections apply to both Windows and Macintosh computers: only the "look and feel" is different. Each tab is shown in a screen shot with the settings described below it.
Saving job options
In Acrobat 4 and 5, named sets of job options are provided as a starting point. We recommend that you start with the "Print" or "Print optimized" settings and then change them as described below. Once you have made changes, click the "Save" button to save the settings with a relevant name (such as "ONAC"), and they will become the new startup settings for the Distiller.
Job option settings
Click your Acrobat version below for job options instructions and screen shots.
All Acrobat versions discussed here provide the "watched folders" feature, which allows you to automate creation of PDF files. You define for Acrobat a folder to watch, and it creates two folders within that folder: one called "in" and one called "out". Whenever Acrobat Distiller is active, it monitors the "in" folder, and when it detects a Postscript file there, it distills it into a PDF and saves it in the "out" folder along with a log file.
If you are using watched folders, you can print several files from the AdobePS printer to the "in" folder. Next time you open Acrobat Distiller, it will distill everything that is there and deposit the finished PDF files in the "out" folder.
ONAC has a reputation for providing relatively problem-free PDF files, and this is because we test each file that we receive before passing it on to the newspapers. Advertisers and agencies can save themselves time and stress by performing these tests before sending out PDF advertising.
For a PDF file to print correctly, all fonts used in the original application MUST be embedded in the PDF. Embedding means simply that the necessary information to render the characters, on the screen and in print, is contained in a font matrix within the PDF. To minimize file size, font information should also be "subsetted", which means that the file contains information about only those characters that are used in the document, rather than the entire printable character set.
When you look at a PDF file on the screen, you cannot tell whether the fonts are embedded. To check for font embedding, you must choose "Document Info" or "Document Properties" from the File menu, then choose "Fonts" from the submenu. Click here for a screen shot. The table lists all fonts in the PDF file and indicates what font and format is being used for the display.
If the "Used font" column says "Embedded" or "Embedded subset" for each font in the list, the fonts have all been embedded. If the "Used font" column contains a font name, that font was not embedded and is being substituted by a similar font on your computer.
If the "Format" column says "Type 1", the font was correctly embedded in Postscript outline format. If this column says "TrueType", the font was not embedded in Postscript outline format and will probably fail to print, or print incorrectly, from a Macintosh computer. Because more than half of Oregon's newspapers use Macintosh production systems, it is important to ensure that fonts are embedded in Type 1 format.
Most newspapers export an EPS image file from the PDF file. The EPS is then imported into a page layout program from which the page is eventually printed to film. This is the preferred method for color ads in particular.
At ONAC, we export an EPS image file from every PDF we receive, then we place the image into a Quark Xpress page. If errors occur during export or import, we will request that a new PDF file be submitted. Especially on color ads or those with complex graphics and layering, advertisers should export an EPS file from at least one sample ad in a group and place it into a page layout program to ensure that this process is error-free.
The final test of a PDF file and its exported EPS is printing from the page layout to a Postscript printer. Font errors and graphic anomalies sometimes don't show up until the image is printed. Again, at least a sample of a complex ad should be printed from an exported EPS to ensure that ONAC will not be requesting a new file.
In the newspaper, bitmap images will be screened at 85 lines per inch, which means that the resolution of color and grayscale images need not and should not be higher than 170 dots per inch (dpi). Excessive image resolution is one of the two main causes of oversized PDF files.
The second main cause of oversized PDF files is inadequate compression of bitmap images. To ensure that your PDF files are optimally compressed, we recommend that you use the job options specified above for compression. These recommendations exceed the quality standards set by the Associated Press for their AdSend digital ad delivery service.
Most advertisers are aware of this, but it is worth repeating: color that is to be printed must be either CMYK (also known as "process") color or spot color. RGB color (the color mode of web graphics and of computer monitors) produces washed-out results and should never be used for print advertising.
Most spot color is written to PDF format in such a way that it is compatible with most newspaper production systems. This includes spot color that is assigned in a page layout program as well as that within separate images created in a graphics program. Newspapers may, at their discretion, recast spot colors as CMYK blends to avoid running extra color units. In most situations, this is easily done by the newspaper.
Photoshop Duotone images are an exception. If you create a duotone image in this special Photoshop mode, the newspaper can separate the spot color but, in most cases, cannot digitally convert it to process color. For this reason, it is best to convert Photoshop duotones to multichannel mode before saving as an EPS file.
Most newer production systems are designed to ignore embedded device profiles unless they are needed, and newer graphics and page layout programs often enforce color management invisibly. If you are using Acrobat 3, PDF files created with later Acrobat versions may contain color management information that is unreadable by Acrobat 3, and Acrobat will produce an error indicating that it cannot find a specific color space. The only solution to this problem is to upgrade to a later version of Acrobat that can handle embedded color management information.