You want to reduce on your Mac large PDF files for certain uses, you can use a special feature of the program "preview". How it works, you will learn in this practical tip.
A PDF file smaller on Mac OS X with on-Board tools
To be able to PDF files on Mac OS X out, you will not need any additional software. The built-in preview application can do this:
You can open the desired PDF document with the program "preview". For example, clicking in the Finder with a right click on the file. From the context menu, select the Option "Open with" and "preview.app".
Now click in the program "preview" on "file" and "Export".
Then, give the file a new name, otherwise the original file will be overwritten in the destination directory.
Select in the bottom pane from the drop-down Box "Quartz Filter" the Option "Reduce File Size" and finally click on the Button [Save.]
As you Mac OS X multiple PDF files to a document, summarize, read here.