When you export to pdf the documents should retain their editability and all text should be "smart" as well as images retain ability to resize and move around. "photoshop pdf" is another thing altogether, I'm not really a fan of photoshop.
I don't know what people usually use for books, I've used indesign a lot but I think it's mainly used for magazines, although I have personally made documents in it that are 80-100 pages, mostly images. Does word imbed the images instead of linking them? That's probably why the file becomes too large.
In Word (which is somewhat unique when compared to other editors - it makes me miss Wordstar...whose keystroke commands Microsoft stole in 1990 and embedded into Word...) the photo images are located by supplying the text coordinates, character archetype and the line format of the 0,0 dot location of the image. In opposition, Wordstar would map the location of the image's 0,0 point and then store the picture in a separate part of the file (at the end, with a sequence number, before the file-end buffer). Wordstar at first didn't save the original picture (or object) size if you trimmed it, at the end it did, though. In Word it saves the image as its full size until you "compress" it and shear it, which then sets the size to whatever you trimmed it to be and ejects the rest of the pixels of the image to shrink the file. This has to be done before 'flattening' it, which then applies any paste-on editing done to the pictures by appending the (x,y) and (object definition) of, in the case of this book, the arrows in the pictures that point out things. The printer hates those...mostly because different flavors of .PDF handle them differently, and Word has used some 8 different methods since the first Windows-on-DOS days, so the final consolidation becomes problematic. That's what I learned since 2 weeks ago...
The original definition of "PDF" in the 1970s world of computing was "Pixel Data Format", defining how dot-matrix printers hit paper with pins (which came directly from the old color TV onscreen painting methods), until ADOBE came along with their "Portable Document Format" term. I remember when there was a battle headed to court over the "PDF" usage and definitions, but this was in the economic death spirals of the 1980s when Microsoft - made when Gates stole cP/M from the public domain, added a serial port handler and floppy-disc manager to it and renamed it "Disk Operating System" and sold it to IBM (which is 100% illegal to do, BTW) - stepped in with tons of $$ and forced it into their control. That's how one company, Microsoft, nearly destroyed the usefulness of the PC until (strangely enough) Europe came to its rescue with Linux. Which I use, and am far happier with. I like running virtual Windows in Linux, which stops all the hardware-stealing corruptive crap that Windows does: it runs faster, with less stalling and crashing, inside Linux than it does on any of my other 21 computers.
