Best compression for JPEG

I am creating a PDF from pages just containing JPEG's with just a title on top. Basically it is 10 pages with 6 JPEG's on each page. Using another PDF printer (ADOBE ACROBAT PRO) it created files of 4mg, while PDFCreator is 13mg. What is strange that other programs like ADOBE ACROBAT PRO cannot make them smaller. What is the best setting to use?