Type1 font is the most widely used font format in the PostScript page description language. PostScript fonts were introduced in 1984. Only a maximum of 256 characters can be used in a font. The character code is not standardized. As a successor, Adobe (together with Microsoft) introduced the OpenType format in 1996. This has the advantage of a larger character set (> 65,000 characters) and a standardized character code (Unicode). In addition, OpenType fonts are platform-independent, unlike Type1 fonts.
This means that in existing and new documents, texts defined with Type1 fonts can no longer be created or edited nor displayed and printed with InDesign and Illustrator updates released starting January 2023. Older versions are not affected. So keep at least one older version when updating in 2023!
Acrobat and PDF are not affected. Type1 fonts will continue to work there. PDF pages placed in InDesign or Illustrator can still contain Type 1 fonts and will be exported correctly.
The latest versions of Creative Cloud applications display warnings when documents with Type1 fonts are used:
However, this will only happen with the latest updates.
Gregor Fellenz has developed a free InDesign start-up script that enables corresponding warnings even with older InDesign versions:Adobe recommends replacing Type1 fonts with OpenType fonts (see list of Adobe fonts). However, there are some stumbling blocks:
- There is no OpenType version for many Type1 fonts available. Often the original font manufacturer no longer exists. You then have to switch to another (similar) font. CD/CI specifications and packaging must be adapted. In the case of packaging (e.g. pharmaceuticals), these often have to be re-approved by the regulatory authorities.
- Often Type1 fonts have been “improved” by the font manufacturers when converting to OpenType (e.g. adjusted widths, kerning). This can lead to new hyphenation, and therefore to underset or (worse) overset text.
- Since the character codes of characters with accents, ligatures, special characters, etc. are not standardized in Type1, character swaps or disappearances may occur with the OpenType font.
- If Type1 Expert fonts (e.g. for small caps, oldstyle figures, special characters, etc.) have been used, the conversion is particularly complicated, because in the Expert fonts these special characters use the character code of a normal character for lack of other possibilities (e.g. “A small caps” uses the code of the “A”). When assigning an OpenType font, which of course in most cases contains small caps (but with different character codes), the small caps are lost and you have to define them again.
- Conversion from Type1 to OpenType by users (e.g. using TransType 4 from FontLab) may be prohibited by the license agreement.
Adobe deliberately made this announcement two years in advance to give users enough time to make the switch.
After converting existing documents with Type1 fonts to OpenType, a thorough check is necessary. A PDF document comparison (before/after the font conversion) can be very helpful (e.g. with Adobe Acrobat Pro, Callas pdfToolbox).