Dear Anne-Marie,

Yes, that was my original intention as well!

But frankly I am not a huge fan of it, having tried it from time to time. My guess is that it is most useful when you have the same export source of the PDF:s you are comparing, and have the same export settings. Otherwise I find it tends to focus on technical differences rather than visual differences, of course this is correct in a way, but at the end of the day you want the page to look right rather than have beautiful code. Checking the technical build up of the file is of course important and something I don't want to be without, but I think this should be handled by the truly awesome Preflight function in Acrobat.

What I would like, just in case the Acrobat developers at Adobe are out there listening, is a compare functionality that skips the nitti gritty PDF code build up differences, but finds and highlights the visual differences. This would check the document page by page and highlight visual differences, in some nice striking accent color. After the comparison you would get a report listing the “difference ratio” per page, like Page3: 0% diff, Page4: 2% diff. etc. So then you can go back to the document and look at the pages that were reported different.

I am thinking this maybe could be done comparing a lowres file with a highres file as well. Or an approved jpg proofing file with the final highres pdf.

I think the closest match here is the “PDF Comparator” from Premedia Systems, as you suggested, David. When testing the trial version it seems to do the trick. Thanks for the advice, guys!