Preview "save as" creates bigger file than input. Why?
I have a PDF of a 12 page document, about 600 KB file size. I open it in Preview, and "save as" another file. The new PDF is about 7 MB file size, more than 10 times the original file size.
Additional info:
1. If I just wanted another copy of the PDF I could copy the file. I know that. But I used Preview with "Create Booklet" and the booklet file was about 7 MB. I used "save as" to show that "Create Booklet" has nothing to do with increasing the file size.
2. The PDF was created in Scribus. Scribus outlines fonts it thinks it's not allowed to embed, and the text in the PDF is almost all in outlined fonts.
3. The font produced from Scribus is about 1.5 KB file size. Processing it with Ghostscript, using "gs -sDEVICE=pdfwrite ..." reduced the file size to about 600 KB.
4. I have another DTP application that embeds the same fonts. The PDF output is a little over 1 MB, Ghostscript shrinks it to well under 1 MB, and it does not become larger when saved from Preview.
Bottom line: After Scribus output and processing with Ghostscript, the PDF has outlined fonts in well under 1 MB file size. Open it in Preview and save it, and the file becomes ten times larger. Why?