Why do pdflatex and latex LNCS outputs look different?

Question

I've found that using embedded postscript (eps) with the pdflatex command, as opposed to the latex command, may require more effort; and potentially insecure write18 permissions with cygwin. No problem, I thought, I can just use latex. However, the two give different results.

I made a test by unzipping the Springer LNCS file llncs2e.zip. In the first case I used:

pdflatex llncs.dem && pdflatex llncs.dem

In the second case I used:

latex llncs.dem && latex llncs.dem && dvipdf llncs.dvi

In the second case I find that the bottom margin appears very large, while the top margin is too small; and don't think this looks acceptable. I'm not looking for a way to fix the margins, but would like to know where I went wrong in assuming that both routes would produce identical output.

Answer 1

The llncs class should work just like the standard article class. You can specify the a4paper option to get A4 paper size, or omit it to get the letter paper size.

With pdflatex, this is all that you need.

With latex + dvips + ps2pdf, you will also need to specify the correct paper size on the dvips command line, for example, dvips -t a4. The dvipdf tool seems to be similar.

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Note that dvips might or might not accidentally produce the correct paper size, depending on the configuration of your system. It might be best not to count on it; always specify the paper size on the command line, or you will have surprises when you try to compile it on another computer.

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Finally, the LNCS books of course do not have the physical paper size of A4 or letter. If you want to produce a PDF file with a paper size that matches the final printed book, here you can find a very useful trick: use pdflatex and specify

\pdfpagesattr{/CropBox [92 112 523 778]}

Answer 2

As far as I can see neither the class nor set the (pdf) paper size. Perhaps you get letterpaper in one case. Apart from this: all the different routes to pdf (pdflatex, xelatex, lualatex, latex+dvips+ps2pdf, latex+dvipdfmx, latex +...) can give different results.