Actually, the problem stems from not the image conversions pointed to in the previous responses, but rather, the settings in the Standard joboptions.
Both HTML and Outlook e-mail message PDFMaker conversions implicitly use the Standard joboptions for conversion settings. Regrettably, there is no ability to point to some other settings such as High Quality Print joboptions.
The best workaround (and I have been using this successfully for a number of years) is to modify the Standard joboptions to be much closer to those of High Quality Print with no downsampling of images unless they are > 450 dpi, use of Automatic (JPEG) compression with Maximum quality, subset embedding of all fonts, and no color space conversions. The got'cha on this solution is that you need to change ownership and protections of the Standard.joboptions file such that you can change it and resave it. Also, updates of Acrobat may overwrite your updated Standards. joboptions file and as such, it is important to save a copy to restore after Acrobat updates.
- Dov