Co.Design asked Tobias Frere-Jones of Hoefler & Co. to give his thoughts on Apple’s choice of Helvetica as an interface typeface for the upcoming OS X Yosemite update:
Despite its grand reputation, Helvetica can’t do everything. It works well in big sizes, but it can be really weak in small sizes. Shapes like ‘C’ and ‘S’ curl back into themselves, leaving tight “apertures”—the channels of white between a letter’s interior and exterior. So each shape halts the eye again and again, rather than ushering it along the line. The lowercase ‘e,‘ the most common letter in English and many other languages, takes an especially unobliging form. These and other letters can be a pixel away from being some other letter, and we’re left to deal with flickers of doubt as we read.
This reminds me of what Erik Spiekerman wrote about Helvetica:
[Helvetica] really wasn’t designed for small sizes on screens. Words like milliliter can be very difficult to decipher. If you ever had to read or write a password with 1, i, l or I, you know the problem.
Still, I wouldn’t keep Lucida Grande for HiDPI displays. With a 2x resolution jump (4x pixels) pixel fitting becomes less of an issue, and pixel optimized typefaces like Lucida Grande begin to look crude in comparison with typefaces made primarily for print. Legibility obviously still matters just as much, but the choice need no longer be bound to fonts optimized for low resolution displays.