I’ve always just accepted the received wisdom that you can’t really link to PDFs very well: you can link to the whole file, but then it’s up to your reader to track down what you actually wanted to link to. In fact, I’ve gotten to keep track of a lot of people’s interest in Rasmus Lerdorf’s idea for funky caching because, as I said at the time, it’s
on page 25 of the accursed PDF file.
However, if you follow that link, you should find yourself on page 25. Apparently, just like with named anchors in HTML, although you can only go to a specific spot if the original author put in named destinations, you can still do quite a bit with links to PDFs. That link goes to an Adobe file describing the ways you can link, which on its own wants to open in “Fit Width” scale, with the Bookmarks sidebar open, at page one, but with the addition of
#pagemode=none&page=5&zoom=150,0,520 will open without the Bookmarks, on page 5, at 150%, at some location down the page that I’m not sure about. The docs only say that “scroll values left and top are in a coordinate system where 0,0 is the top left of the page” without mentioning what scale, if any, the coordinate system uses. For me, at 1024×768, that direct link puts it right at the page=pagenum section, but I’d be interested in hearing if it doesn’t at other resolutions (or at the same resolution, for that matter).
[Via a comment at Roland Tanglao’s, where I was planning on chiming in on the original “PDFs are evil because you can’t link to anything but the blob” post.]