Strange. When printing contact sheets as a PDF-file, I have to choose 'No color management', otherwise all the images look like negatives on the PDF. Why is that?
(Reason to make PDF's? It's a simple way to show a lot of pictures to the customer. Printing 200 pictures as a page by page contact sheet into a Low Res PDF-file in Instant Enfocus generates a file of only 10 MB, including the filenames. PS doesn't offer that possibility and that's why I like PM so much!)