Hi, Jo-Jeff,
I answered your first post (posted in the wrong thread), so I'll copy my post here.
I'm not seeing the problem in the images you posted here -- can YOU see the lines in your second image posted?
What program did you use to convert the file to PDF format?
Where are the lines -- vertical, horizontal? Do they appear only in certain parts of the image or throughout? Were there lines in any part of your original during any part of your Photoshop process?
I convert Pagemaker files and other files to PDFs using an older version of Acrobat, and they always show ONLY what I have in the original, so I don't have any answer for you.
Hopefully, someone here will be able to help.