The information in this document assumes you are using Acrobat 4x. If you are new to Acrobat 4x, you should be aware that there is no longer an
application called Exchange. The features of Exchange 3x are built in to Acrobat 4x.
Docs created in Acrobat 4x can be viewed with Reader 3x. However, some features included in 4x are backwards incompatible. Knowing this, Adobe's default setting in 4x for all docs prepared with Screen optimization is 3x compatibility. Defaults for Print and Press are 4x compatibility.
Do I embed and/or subset?
These are two huge questions.
The answer. Unequivocally yes and yes. And sometimes no.
What does embedding do?
The embed option tells Acrobat Distiller (or PDF Writer) to embed the definitions of all fonts into the PDF file. However, the Base 14 fonts (Times /Mac or Times New Roman PS MT /Win, Helvetica / Mac or Arial MT / Win, Courier, Symbol and Zapf Dingbats) are not embedded by default in
Screen Optimized documents or documents created by the PDF Writer. The reason for this being that the full Acrobat application and the free Acrobat Reader includes these fonts. Therefore, Distiller assumes that these fonts will be available by any viewer.
You may create your own settings and embed, subset, or choose not to embed any font depending on your particular requirements.
Exception: One can embed the Base 14 fonts using the PDF Writer in Windows by changing the settings in the printer Properties window. Macintosh users are unable to modify the PDF Writer driver, thus the Base 14 fonts will not embed in documents created with the PDF Writer on a Mac.
Recommendation: Always embed fonts, unless file size is of primary concern, or if you are using the Base 14 fonts in docs primarily intended for screen viewing. Non-Base 14 fonts should be embedded in all documents for accurate viewing and printing.
When you embed a font and the viewer has a font with the same name installed on his system, even if the font is made by a different foundry, the PDF file will be read with his system fonts.
The reason it's important to understand this point is that if you wish a viewer to view your document with your fonts, then you also need to subset your fonts, in addition to embedding.
Note: Adobe Type Manager (ATM) must be installed and loaded for the PDF Writer to be able to embed Type 1 PostScript fonts.
How Acrobat Viewers retrieve font information.
An Acrobat Viewer completes a series of steps to retrieve font information when opening a PDF file. It first checks the PDF file for font information, such as embedded or subset fonts, and if available will use that font information for display and printing. If there is no font information in the PDF file, the Viewer checks to see if the fonts specified are in its Resources:Fonts folder. If they are, the Viewer uses them.
Note: If the PDF file contains text formatted with Helvetica or Times, and these fonts are not embedded, the Viewer will use Arial MT or Times New Roman PS MT from the Resources:Fonts folder for Helvetica or Times, respectively. The Viewer will do this even if Helvetica or Times is active on the system.
Suggestion: If you use styles of Helvetica or Times in your doc other than regular, oblique, bold and bold oblique, it would be a good idea to build your file with Type 1 fonts only, and embed the fonts in your file.
If the fonts aren't in the Resources:Fonts folder, the Viewer checks to see if the fonts are active on your system. If the fonts are active, the Viewer uses them.
What happens if I do not embed?
If a font is not embedded in a PDF file and the user who opens a file does not have access to the original font, Acrobat will temporarily substitute the font with a serif or san serif typeface made with Adobe's Multiple Master technology. With the font metrics included in the PDF, the fonts are stretched or condensed to ensure no reflow. However, it is important to understand that the fonts are lookalike only, and particularly with unconventional or script faces, they may not lookalike at all.
Subsetting is critical for proper viewing, printing or ripping.
Subsetting is a process in which each font used is included (subset) in the file. The larger the subset threshold, the smaller the file size, as only the characters used in the file are subset. So if you are doing simple reports, stick with Times and Helvetica which will minimize your file size.
What setting do I use?
If you want the smallest file size, and assurance that the document will view as you
created it, subset at 100%. It used to be that Adobe's default setting was 99%; but in
Acrobat 4x it is now 100%. If you are preparing a PDF for press, ALWAYS subset at 100%.
When Distiller embeds a subset of a font in a PDF file, it assigns a new, unique name to the font derived from the name of the original font. Because the names of the subsetted fonts in the PDF file will never match a font on a host system, the viewer will always view and print using your version of the fonts.
Note: The default subset setting for the PDF Writer (which you should not use except for simple text documents -- and never for files destined for press or with eps graphics included) is 35% and cannot be changed. If you need to subset at 100%, do not use the PDF Writer.