Interestingly, the PDF files contain the unrasterised line art; when OSX Preview shows the pages, it draws it in layers, first the neat shapes of colour, then outlines and shading, then speech/thought bubbles and text.
Interestingly, the PDF files contain the unrasterised line art; when OSX Preview shows the pages, it draws it in layers, first the neat shapes of colour, then outlines and shading, then speech/thought bubbles and text.