Saturday, May 14, 2011

Font Formats

PostScript Type 1, TrueType and OpenType font formats are all multi-platform, outline font standards. Multi-platform (or cross-platform) means that the fonts can be used on different types of computer operating systems, Windows and Mac for example. The term “outline” means that the font defines the form of the letter (the character or glyph) through mathematical formulas which define lines and curves. TrueType and PostScript fonts each use different mathematics to describe their outlines while the OpenType format can use both TrueType and PostScript outlines.

PostScript Type 1: The Postscript Type 1 format, created by Adobe, requires two files for each font, namely the screen font (containing the metrics and other information needed to display the font properly on the computer screen) and the printer font (containing the actual PostScript typeface). PostScript is an industry-standard page description language (PDL) used to describe text, graphics and images for printed pages in publishing and graphic design. Consequently, the PostScript font format has traditionally been the preferred font format for use in those industries. Back in the day, when I wanted to send a completed design job to a print shop, I had to include the fonts that were used with the job. If I used Type 1 fonts  I had to make sure I included both the screen font and the printer font files. With PostScript being the industry standard in high-end print shops, I invariably used PostScript Type 1 fonts in my designs.

Type 1 fonts are limited to approximately 256 glyphs per font. PostScript font files are also platform specific, meaning that there are different versions of PostScript fonts for use with either the Mac platform or the Windows platform.



Adobe Font Icons

TrueType: TrueType fonts were originally created by Apple but the technology was then licensed to Microsoft. TrueType is a cross-platform format meaning it can be used on both Windows and Mac platforms. TrueType fonts require only one file per font with both the screen font and the printer font components contained in that single file. Like Type 1 fonts, TrueType fonts are limited to 256 glyphs per font.


TrueType Font Icon

OpenType: OpenType is the newest font format and is likely to supersede both Type 1 and TrueType. It was developed jointly by Adobe and Microsoft. It is a cross-platform font format working on both Windows and Mac platforms. Like TrueType, OpenType fonts consist of a single file which contains all the necessary font components (the outline, metric and bitmap data). Unlike Type 1 and TrueType, Opentype fonts can contain up to 65,000 glyphs. An excellent description of the OpenType font format can be found at Adobe’s web site.


OpenType Font Icon

OpenType fonts come in two varieties, namely CFF and TTF. OpenType fonts of the CFF type are designated by the file extension .otf and are PostScript Type 1 fonts. OpenType fonts of the TTF variety are designated by the file extension .ttf and are TrueType fonts. TTF (.ttf) Opentype fonts are a better choice if you are working on a Windows platform or are doing work that is only going to be viewed on a computer screen. This is because TrueType fonts have better “hinting”. Hinting involves embedded instructions which control how an outline font is rasterized and determines how clearly and legibly the font displays, especially at low resolutions.  CFF (.otf) OpenType fonts are the best choice if you are working on a Mac platform or are doing print work.

Free Vs. Commercial Fonts: There are several reasons to only use fonts purchased from reputable font foundries as opposed to free fonts. Some TrueType and Opentype fonts can contain restrictions which do not allow them to be embedded in a PDF file. These fonts are not licensed for commercial use. Such restricted font files should not be used in print production. Also, free fonts often lack the quality and craftsmanship found in commercial fonts and they tend to be very limited in their character sets. There are also ethical considerations, since some free fonts may actually be commercial fonts which someone purchased then posted on the web.

Finally: According to Printing.org, “You can use TrueType, OpenType and Type 1 fonts interchangeably in your page layout. Each typeface will produce equal results and print properly on all up-to-date RIPs. (http://www.printing.org/page/2775)

_____________________
Sources:
Anonymous, OpenType, Publishing Date Unknown, Retrieved 5/9/2011 from Adobe.com. (http://www.adobe.com/type/opentype/)


Anonymous, Fonts: Bitmap, PostScript, and TrueType Compared, Last Modified 10/03/2008, Article: TA21573, retrieved  5/12/2011 from Apple.com. (http://support.apple.com/kb/TA21573?viewlocale=en_US)


Anonymous, Font Formats, Published 8/19/2008 (updated 5/13/2009), retrieved 5/11/2011 from Printing.org. (http://www.printing.org/page/2775)


Phinney, Thomas W., TrueType, PostScript Type 1, & OpenType: What’s the Difference?, Version 2.22, 12/5/2002, Retrieved 5/11/2011 from Scribd. (http://www.scribd.com/doc/202365/TrueType-PostScript-Type-1-and-OpenType-Whats-the-Difference)


Marin, Joe, When You Shouldn't Use a Font, Published 5/13/2009, Retrieved 5/9/2011 from Printing.org. (http://www.printing.org/page/5352)


Anonymous, What is the Difference Between TrueType, PostScript and OpenType Fonts,  Publishing Date Unknown, Retrieved on 5/14/2011 from Herff Jones Yearbooks, (http://www.yearbooks.biz/?event=FAQ.Detail&faq=2)


Bear, Jacci Howard, Why Buy Fonts When There are So Many Free Fonts on the Web?, Retrieved 5/14/2011 from About.com (http://desktoppub.about.com/cs/fonts/f/why_buy_fonts.htm)


Strizver, Ilene, Which Flavor of OpenType iIs Best?, Published on 4/13/2011, Retrieved on 4/21/2011 from CreativePro.com (http://www.creativepro.com/blog/typetalk-which-flavor-opentype-best)

No comments:

Post a Comment