I'm trying to define a "standard template" for drawing figures for my Ph. D. thesis. I would design large figures to fill the whole textwidth. Sometimes, however I have smaller figure, so that 2 (rarely 3) fit on "one line", and I also want to create a template for them with width<0.5 \textwidth resp. <0.33 \textwidth.

(I want to create all figures if possible in "real" size directly to avoid different font sizes later when they would be scaled by the \includegraphics[width=...] command).

I wondered how the width of the figures should be - compared to the textwidth. For large figures, the question was already discussed here Typographic conventions for width of figures in LaTeX data analysis reports and there was an interesting and detailed answer from Geoffrey Jones.

The question not discussed there is:

• How much free horizontal space should be left between figures, of 2, 3 or 4 of them are shown as subfigures over the textwidth?

So:

• Is there a typographic rule (or rule of thumb) stating, how much free space is at least "necessary" to visually separate different subfigures?
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I suspect there is no strict rule for this. Add as much space as needed to make it look good. I'd start with \quad and \qquad. This, of course, depends on how much border space do the figures have themselves. –  Andrey Vihrov May 8 '11 at 14:52
sure, the border space is a very important point - it might be a difference, if the figure is a photograph or a line art with much white space around. –  MostlyHarmless May 8 '11 at 15:05

In the first page the space between the figures is 5% of \textwidth, the rest one space. I prefer the more compact last ones. I suggest you experiment with different spacing to see what is right for you.