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The Math of Text Readability
An anonymous reader writes "Wired magazine has an article that explains The Law of Optical Volumes, a formula for spacing the letters on a printed page that results in maximum readability. Wired's new logo (did anyone notice?) obeys the law. Unfortunately, Web fonts don't allow custom kerning pairs, so you can't work the same magic online as in print. Could this be why some people still prefer newspapers and magazines to the Web?"
I have actually written software to kern text (for the sign-making industry) and can testify that kerning is not an exact science. Yes, one needs to even up the areas of white space between letter, but then one needs to bias the calculations in favour of the tops of the letters. And then make some allowance for any white space inside the letters, and .... and .... and ..... Spacing that is correct for 12-point type on paper would be quite wrong for a huge 3D sign on the side of a building, and so on.
For perfection, there is no substitute for the human eye. The algorithms used by our brains to unscramble text are very complex.
Web fonts don't have custom kerning pairs
;)
Whilst true, this is a bit misguided.
First things first - web fonts, and print fonts are the same. Fonts are fonts. Some are better than others and include more default kerning pairs than others. But rest assured, Georgia, Arial etc have got kerning pairs (for print and screen) and hinting information (for screen).
Type rendering engines *do* support kerning pairs, that the typographer who designed the font decided to create and embed in the font file. There are a bunch of patterns that are used to expose badly spaced pairs that typographers use when checking these spaces and fixing them.
Custom kerning for print is actually font independent and is done in the print design app of choice. Print design uses these same font files and their kerning pairs, and print designers won't custom kern large blocks of text, unless of course they want to spend 3 days per page of content. Print designers do often kern large headings and logotypes where any subtle problems are (literally) magnified and are obvious to the reader. Online designers do this in a number of ways, but typically resort to using an image (because the logotype font isn't likely to be on the end users computer anyway). CSS does give you the ability to create custom kerning pairs if you would want it, through a mixture of text-indents, spans and margins but its not very clean.
So the author if this piece is correct, but a little misguided and not being particularly fair on "the web".
I'm just running an incredibly modern-futuristic computer here, but my computer arranges letter closer together and further apart depending on their shapes... is that different from 'kerning'?
Related, but more different than not.
There are monospaced fonts, where each letter takes up the same amount of space regardless of shape, so xxx and iii are the same width. Then there are proportional fonts, where the letters are as wide as the rectangle it takes to contain them, so xxx is much wider than iii. This is what you're thinking of.
Kerning takes it a step further. A proportional font that doesn't have some kind of hinting (and a program that can read/implement that) will still put too much space between the letters VA, while one that does will allow the V and A to 'invade' each other's rectangle. It can get quite complex with all the different glyphs (letterforms) that have to work with each other.
I'm mystified as to who would say computers can't do this, since I use them to do exactly that every day. It really has more to do with the fonts and applications (and possibly the OS) you are using.
One man's -1 Flamebait is another man's +5 Funny.
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no it doesn't. It looks like it might when you just look at the two letters together... but it's just an illusion. (see above example).