Peter, Yes, it "looks like" the links are missing, but they are not. If you reread my post, you'll see that the only thing that changed is that the original document was open when exporting at first versus the book was open but the document wasn't when exporting the next time. It's the exact same file, with the same links.

BTW, I have restarted both ID CS 4, and my Mac. Same problem.

I'm running ID CS 4 6.0.6 and Mac OS 10.6.8, and I have 8GB of RAM.

They are all in the same folder. In fact, they are to the same images shown in full at right in the example image I posted. In other words, the full image of a banknote appears at right and is fine in high-resolution, but the signatures are low-res, even though they link to the exact same file, and just show a portion of the image at magnification.

I appreciate the intention to help, but can you answer my basic question: When exporting a book, does ID CS 4 need to have all the documents open for the process to work properly?

Peter, per my original post "I did several tests and it appears that if I open all the documents which comprise the book, all the images in the exported PDF are high resolution as desired. However, ultimately I want to create a book with 120+ documents, and there's no way I can keep them all open in memory without ID crashing. Yes, I suppose I can open a subset of the documents, export them, then combine the PDFs in Acrobat, but that's a cludge workaround."

I just checked the Preferences for File Handling. In the Links section, I selected all of the options except Create Links When Placing Text and Spreadsheet Files since I don't have any in my documents.

Now when I export a book with multiple files, it seems to work as expected. I'm not exactly sure why these preferences are affecting the output resolution of some images and not others, but at this point, I don't care.

Peter, thanks for your attempt to help, which ultimately pointed me towards the solution.

Nope, no Suitcase conflict here. Just an unexpected behavior from this File Handling preference. Annoying, but at least now I won't waste more time pulling out hair I don't have on my head.

The frustrating this is that the links ARE up to date. It's as if InDesign is using low-res placeholders for the exported PDF.

Reset all warnings and disabled the file handling prefs. Still no warning, and same old problem of low-res proxies. Frustrating as heck, but now that I stumbled upon the fix, I'm OK.

Harold,

I just checked the Preferences for File Handling. In the Links section, I selected all of the options except Create Links When Placing Text and Spreadsheet Files since I don't have any in my documents.

Now when I export a book with multiple files, it seems to work as expected. I'm not exactly sure why these preferences are affecting the output resolution of some images and not others, but at this point, I don't care.