More Old Mac Font Memories

Dr. Drang, writing at And Now It’s All This:

Back before the LaserWriter and PostScript (it’s an all InterCaps day here at ANIAT) made resolution independence commonplace, most printers were of the dot-matrix variety, usually at a fairly low resolution. The original ImageWriter had a higher resolution than most: 144 dpi. And this led to the interesting feature.

You may have noticed that the 144 dpi resolution of the ImageWriter is exactly twice that of the Mac’s 72 dpi screen. The ImageWriter printer driver on the Mac took advantage of that. If you were writing a document using a 12-point font, and your Mac had a 24-point version of that font, the Mac would send the 24-point font’s bitmaps (all Mac fonts were bitmapped in those days) to the printer so it could render smoother text.

The upshot of this was a very slight breaking of the WYSIWYG principle. On the screen, your Geneva 12 document would appear with curly ys, but when you printed it out, it would have straight ys. A fun idiosyncrasy that disappeared when PS fonts and Adobe Type Manager took over.

I used ImageWriters a lot when I was using Apple II’s, but almost never from the Mac. When I got my first Mac in 1991 it came with a StyleWriter, a rather dreadful inkjet printer. (At the very least it was dreadfully slow.) But I do remember this curiosity with the different style y glyphs when printing text set in Geneva to an ImageWriter. The 144/72 DPI thing was perhaps Apple’s first @2× “double resolution” trick.

Here’s a copy of Apple’s 227-page (!) user manual for the ImageWriter II from 1985, which includes copious examples of source code in both Applesoft BASIC and Macintosh Pascal. It even contains instructions for designing your own custom bitmapped character glyphs.

Bonus points to Drang for including a screenshot illustrating that you chose font sizes from the Style menu (in a separate section underneath the actual, you know, styles) in early versions of MacWrite.

★ Thursday, 15 May 2025