Magnifier in Preview for Lion

By Richard Mallion
Sometimes  when viewing documents in Apple’s Preview application, especially PDFs, I need to zoom into a specific part of the document to look at some fine detail.
Preview for Lion has a nice magnifier. This is in addition to the standard zoom in/out which applies to the whole document.
To activate the Magnifier tool, select from menu Tools->Show Magnifier or simply press the backtick ` key.
A rectangular view will be displayed once the tool is activated displaying the area of the document you are viewing. You can move the rectangle and adjust the size of the rectangle using pinch gesture.