All PDF proofs must be opened in Acrobat Reader (or Acrobat Pro) for the most accurate viewing.
Do not use
Applications such as viewers within internet browsers (such as Firefox, Internet Explorer and Chrome) and other PDF software (such as Apple Preview) are not suitable for viewing print-ready PDF files. Smart phones and tablets are not suitable for proofing either.
The rendering engines in these software applications are not as powerful or accurate as Acrobat Reader and hence not suitable for proofing purposes.