The attraction of PDF for authors is that the reader will supposedly see the document formatted in the same way as the author (however, incomplete PDFs often ruin that). This makes some sense for paper, where the size is standardized; but it does not make sense for screens, which come in many sizes and resolutions, from the 10" 640*480 notebook screen to the 21" 1600*1200 CRT, in monochrome or colour. (Actually, if we consider people with bad eyes, fixed formatting is not even a good idea for paper; it's just an artifact of mass reproduction techniques like the printing press.)
Authors should forget about complete control in such an environment, unless they want to inconvenience their readers. It is much better to describe the document structure, and leave the formatting to the browser, guided by the reader's preferences. That's the idea behind standard HTML. Try to get by with it. (Note that many Netscape "extensions" to HTML are contrary to this spirit, and indeed, documents employing them often look badly when displayed with a different window size, font, or colour depth than they were designed for; not to mention how they look on non-Netscape browsers).
As you can see below, gzipped Postscript is almost twice as compact as gzipped PDF and more than twice as compact as plain PDF.
Size File&Format -rw-r--r-- 1 anton vip 1041321 Nov 9 11:45 intel-opt32-ap526.ps -rw-r--r-- 1 anton vip 411050 Nov 8 18:30 intel-opt32-ap526.pdf -rw-r--r-- 1 anton vip 329586 Nov 8 18:30 intel-opt32-ap526.pdf.gz -rw-r--r-- 1 anton vip 181135 Nov 9 11:45 intel-opt32-ap526.ps.gzIn this example, the Postscript was generated from the PDF file, which contained no links. The conversion to Postscript was performed with xpdf 0.7. The original file is the Intel Architecture Optimizations Manual; you can get it here (but only a newer version, I used 24281601). With xpdf 0.7a (encryption) the Postscript output and it's compressed form is more bloated, but the ps.gz is still much smaller than the .pdf:
-rw-r--r-- 1 anton vip 1353166 Jun 10 13:55 xxx.ps -rw-r--r-- 1 anton vip 254710 Jun 10 13:55 xxx.ps.gzAnother example is the files available here. These were converted from Postscript into PDF with ghostscript 5.01. The sums of the file sizes are:
.doc (Winword): 2.885.849 .ps (with Winword from .doc): 4.959.680 .ps.gz: 1.346.021 .pdf (with gs-5.01 from .ps): 1.704.794 .pdf.gz: 1.441.079Interestingly, here converting the PDF back into Postscript with xpdf 0.7a (encryption) results in .ps.gz files that are larger than the .pdf files (unfortunately, xpdf 0.7 does not work on these files):
.ps (with xpdf 0.7a from .pdf): 9726203 .ps.gz: 2186707The following shows more examples (all converted from PDF to Postscript using xpdf 0.7a (encryption), compressed with gzip -9); I did not select these files for compressability (except manual.ps, which I downloaded because its author claimed that it is an example where PDF is more compact than .ps.gz), these are just all the PDF files that happened to be in my download directory (plus intel-opt32-ap526.pdf).
.PDF .pdf.gz .ps .ps.gz .ps.gz/.pdf 243943 190754 656255 123315 51% PRG.pdf 846435 455866 1037500 280930 33% ThinkingInPostScript.pdf 5996975 5894534 12689450 5443575 91% allconnr.pdf 306033 262771 1436313 270212 88% manual.pdf 1986820 1605659 5184809 944873 48% pem32b.pdf 1398720 547655 3108610 471592 34% k6-2-optimization.pdfAnother example is one of my own papers, where the original ps.gz file takes 63484 bytes (298500 bytes uncompressed), whereas the PDF (converted by Peter Knaggs) takes 169520 bytes, a factor 2.67.
A good example of how to do it is the Supercomuting'96 proceedings CD. It contains all the papers in HTML and Postscript forms. (The only negative point I have noticed is that the table-of-contents does not work with my browsers).
For those of you who happen to have a PDF reader but not a Postscript reader, look at the Ghostscript Home Page for relief.