How to view a PDF at its original size? A friend sent me a PDF with a UI mockup claiming it is 1024x768.
It is, indeed:



However, View > Actual Size (⌘0) zooms in so much that the PDF takes up almost all 1920x1200 screen estate that is available.

How do I view the PDF at its original size?
Turns out, there's a Preview preference that controls what actual size actually means:



If you want points to correspond directly to physical pixels, choose the first option.
(Not sure how it affects Retina displays though!)