Reduced PDF file size in Mac OS

Open ColorSync Utility in the Utilities folder off of the Applications folder. ColorSync Utility can create new Quartz filters. Open up ColorSync Utility and switch to the “Filters” pane. This will list all of the filters that you currently have available.
  1. In the lower left, click on the “+” button. This creates a new filter.
  2. Give the filter a name, and press return.
  3. To the right of the filter’s name, choose the down arrow. A menu will pop up.
  4. From the pop-up menu, choose “Add Image Effects Component”, and from that menu choose “Image Compression”.
  5. Adjust the image compression Mode to JPEG.
  6. Adjust the image compression quality however you prefer.
  7. The next time you use Preview to “Save As...”, you'll have a new option under Quartz filters.