What’s wrong with \newfont?

If all else fails, you can specify a font using the LaTeX \newfont command. The font so specified doesn’t fit into the LaTeX font selection mechanism, but the technique can be tempting under several circumstances. The command is merely the thinnest of wrappers around the \font primitive, and suffers from exactly the problems with font encodings and sizes that are outlined in using Plain TeX commands in \LaTeX.

Almost all fonts, nowadays, are provided with LaTeX control files (if they’re adapted to TeX at all). There is therefore little gain in using \newfont.

One temptation arises from the way that LaTeX restricts the sizes of fonts. In fact, this restriction only significantly applies to the default (Computer Modern) and the Cork-encoded (T1) EC fonts, but it is widely considered to be anomalous, nowadays. In recognition of this problem, there is a package fix-cm which will allow you to use the fonts, within LaTeX, at any size you choose. If you’re not using scaleable versions of the fonts, most modern distributions will just generate an appropriate bitmap for you.

So, suppose you want to use Computer Modern Roman at 30 points, you might be tempted to write:

\newfont{\bigfont}{cmr10 at 30pt}
{\bigfont Huge text}

which will indeed work, but will actually produce a worse result than

\usepackage{fix-cm}
...
{%
  \fontsize{30}{36}\selectfont
  Huge text%
}

Note that the fix-cm package was not distributed until the December 2003 edition of LaTeX; if you have an older distribution, the packages type1cm (for CM fonts) and type1ec (for EC fonts) are available.

fix-cm.sty
Distributed as part of macros/latex/base (gzipped tar, browse) (an unpacked version is available at macros/latex/unpacked/fix-cm.sty)
type1cm.sty
macros/latex/contrib/type1cm (gzipped tar, browse)
type1ec.sty
fonts/ps-type1/cm-super/type1ec.sty (the package is actually part of the fonts/ps-type1/cm-super (gzipped tar, browse) distribution, but it works happily in the absence of the scaled fonts)

This question on the Web: http://www.tex.ac.uk/cgi-bin/texfaq2html?label=newfont