I recently was given the challenge of reducing a large, text-filled pdf file to 50% of its size. Unfortunately, I had to figure out how to do this without losing too much of the document’s quality, and I don’t have Adobe Acrobat on my MacBook Pro. No, Preview could not reduce the size and maintain a reasonably legible quality. After many trails and just as many errors I found an article on how to use ColorSync Utility to reduce the size of a pdf. In short, here’s how it is done: