# Shouldn't there be larger sizes of the CM math fonts?

In a poster I'm making I wanted to use 17-point Computer Modern. I noticed that when entering math mode LaTeX switched from cmr17 to cmmi12 to cmsy10. Surely this can't be good style? And cmsy10 even controls things like superscript positioning, so LaTeX is using placement designed for 10-point when I specified 17-point!

True, Knuth didn't design cmmi17 or cmsy17, but probably only because he had no use for it? In any case, it's available using the Sauter extension, but I still couldn't find any Type 1 version. However, it's at least easy to generate the metrics for cmsy17, which would fix the superscript positioning. I'm considering doing that manually...

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Include the fix-cm package, or use the lmodern package that has fonts based on Computer Modern. –  Werner Apr 18 '12 at 16:28
For making posters it is not a good idea at all to use large design sizes! They are for fairy tale books or the like. I advise to make the poster as a normal document at much smaller page size (with fonts of usual design size) and magnify when printing. –  Stephan Lehmke Apr 18 '12 at 16:31
@Werner I was using fix-cm and lmodern doesn't seem to have any larger sizes for the math fonts. –  cbright Apr 18 '12 at 17:10
@StephanLehmke This was for a prominent line, basically the subtitle. I thought it looked better. –  cbright Apr 18 '12 at 17:10
The larger the design size is, the harder the font gets to read, in particular for cmr. I find cmr17 immensely hard to read because the strokes are so thin compared to the size of the letters. It is meant for a few words (like "The TeXbook") on the title page. cmr5...cmr17 are all meant for a reading situation when you are holding a book in your hand. Standing in front of a poster is completely different. Larger distance, inconsistent lighting, bad angles. You move while discussing different things, people are moving around you. You should do all you can to make it easy to read. –  Stephan Lehmke Apr 19 '12 at 4:42

I don't know whether this is the case for you, but in general I recommend not to use large design sizes for posters.

As you can see from the few fonts which actually exist in 17pt design size, this was meant for a few words on a title page, if at all. I find cmr17 immensely hard to read because the strokes are so thin compared to the size of the letters.

If you look in the TeXbook, you'll see that Don Knuth himself didn't use cmr17 at all (which probably wasn't around at the time of writing it), and cmr12 only once, for a concert program. He used cminch for the title page.

The larger the design size is, the harder the font gets to read, in particular for cmr. cmr5...cmr17 are all meant for a reading situation when you are holding a book in your hand. Standing in front of a poster is completely different. Larger distance, inconsistent lighting, bad angles. You move while discussing different things, people are moving around you. You should do all you can to make it easy to read.

I advise to make the poster as a normal document at much smaller page size (with fonts of usual design size) and magnify when printing.

\documentclass[landscape,a4paper]{article}

\usepackage[top=10mm,bottom=10mm,left=10mm,right=10mm]{geometry}

\usepackage{lipsum}

\usepackage[latin]{babel}

\usepackage{microtype}

\font\testv=cmr5 at 10pt
\font\testviii=cmr8 at 10pt
\font\testx=cmr10 at 10pt
\font\testxii=cmr12 at 10pt
\font\testxvii=cmr17 at 10pt

\begin{document}

\parbox[t]{5cm}{\testv\lipsum[1]}\hfill
\parbox[t]{5cm}{\testviii\lipsum[1]}\hfill
\parbox[t]{5cm}{\testx\lipsum[1]}\hfill
\parbox[t]{5cm}{\testxii\lipsum[1]}\hfill
\parbox[t]{5cm}{\testxvii\lipsum[1]}
\end{document}


Decide for yourself which is more readable ;-) Btw, acroread is doing a great job on enhancing readibility on screen. Printed the effect will be much more prominent.

As I said, it may well be that all this isn't relevant to you.

But for posters authors are frequently searching for a "14pt" or a "17pt" option in the hope of getting larger print, and this is wrong. Even "12pt" is harder to read for cmr in my opinion. If this is not the case for you, fine. But a title in cmr17 should be really short to be still readable, no need for maths there.

So just sayin'

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Thank you for your detailed response; I see why larger math fonts would be low priority. But for example the cm-super package has the CM fonts up to 36pt (presumably for things like large titles) so I'd say there should also be the corresponding the math fonts; in some titles you might want a math symbol or two. –  cbright Apr 28 '12 at 1:00
In my case, the text in question was being displayed at 64pt... not sure if you would consider a 6.4 magnification ratio for cmr10 to be too much or not (I guess on a poster it's not as bad). The magnify-when-printing approach wasn't possible for the particular demands of this project---the poster also contains text displayed at 8pt (which of course isn't supposed to be read at a distance!). –  cbright Apr 28 '12 at 1:29
@cbright cmr sizes above 17 are really really non-standard. Searching with Google, discussions about this (see also Sauter fonts) date back to the 90s (compare groups.google.com/d/msg/comp.text.tex/PZjFJHkMeBM/K7K8FMqynrUJ). It's strange these things crop back up today in this guise. This was completely new to me. Personally, I'd ignore everything beyond cmr17. –  Stephan Lehmke Apr 28 '12 at 2:58
@cbright I didn't want to "forbid" you to use cmr17 for a title. But considering how rarely they are really useful, it's improbable someone will go and design a flock of matching math fonts for it. So if you need math, cmr12 might still be the better match. And I wouldn't worry about scaling because (a) most other fonts don't offer design sizes at all (b) cmr is on the "skinny" side even at 10pt. –  Stephan Lehmke Apr 28 '12 at 3:03