# Different numbers on computer modern fonts

Do the different numbers on the computer modern fonts only correspond to their point size. (Not sure if that's how to phrase it, e.g. 10 point font.) Do they actually look different as well? My math professor used cmr12, and I love it, but I feel like it's different from say, cmr10, in ways more than just size.

• If you are asking if fonts are merely scaled to different sizes, the answer is a definite "no". – Steven B. Segletes Dec 17 '14 at 2:18
• Computer Modern has optical font sizes. That is, the design of the glyphs is altered according to size e.g. smaller sizes use somewhat thicker strokes to ensure they remain legible. Also, I think Computer Modern, like Latin Modern, offers different styles of figures, as well. Latin Modern offers at least 4 styles of figures, as well as optical sizes. (Proportional lining, proportional tabular, oldstyle lining, oldstyle tabular.) So it is hard to know just what you are asking about exactly. – cfr Dec 17 '14 at 2:25
• Somewhat related: How to get an even smaller font? – Werner Dec 17 '14 at 2:59
• This page gives a very nice description of why they don't scale: adobe.com/type/topics/opticalsize.html – Steven B. Segletes Dec 18 '14 at 2:46

If really one picture is more valuable then thousand of words:

\documentclass{article}

\begin{document}

\font\cmrs=cmr5 at 2cm
\font\cmrb=cmr14 at 2cm

\cmrs a \cmrb a

\end{document}


Do they look different?

• Do you know where I can find documentation on cmr12? I looked around and couldn't find anything. – user41692 Dec 17 '14 at 10:27
• @Anthony -- all the parameters that went into producing the (original metafont) computer modern fonts are listed in the book computer modern typefaces, volume e of the computers & typesetting series by knuth. not available as an e-book as far as i know. you can get the details of the cmr12 metrics by running tftopl cmr12.tfm cmr12.pl, but i'm not sure the output will be entirely scrutable – barbara beeton Dec 17 '14 at 13:39
• @barbarabeeton I had looked through that book, and there wasn't information on cmr12, only on things like cmr10 or 11... I think. I've read that cmr12 is not standard. Is this correct? – user41692 Dec 17 '14 at 22:18
• i've got the book open, and on pp.12-13, the second column shows cmr12. there's also a brief showing on p.555. the copy i have is a first edition, from 1986. my colleague has the millennium edition, including "the final corrections made in 1998", and it's the same. no, cmr12 is one of the original fonts created with metafont by knuth. (i'd have to check regarding cmr11 though; that may be an interpolation.) – barbara beeton Dec 17 '14 at 22:31
• I'm just crazy. I'll look again. Thank you! – user41692 Dec 18 '14 at 21:33

As indicated in my comment, font designers do not merely scale fonts at different sizes, but do other things to increase legibility.

To demonstrate this, I scale the same string at different sizes to the same final vertical height. One can see that the smaller font sizes are horizontally stretched.

\documentclass{article}
\usepackage{scalerel}
\begin{document}
\def\x{xhat}
\parbox[t]{.5in}{
Actual:\par
\x\par
\small \x\par
\footnotesize \x\par
\scriptsize \x\par
\tiny \x
}
\parbox[t]{.5in}{
Scaled:\par
\x\par
\scalerel*{$\small \x$}{\x}\par
\scalerel*{$\footnotesize \x$}{\x}\par
\scalerel*{$\scriptsize \x$}{\x}\par
\scalerel*{$\tiny \x$}{\x}
}
\end{document}


To show this with the numerals, I changed \x to 0123456789, and made the \parboxes 1 inch wide.