Preview app in Mac OS X Lion has a new Magnifier loupe feature

Preview app in Mac OS X Lion has a new “Magnifier” tool that allows you to zoom into specific portion of document with a loupe view. 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.

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A loupe view will be displayed once the tool is activated. You can move the loupe and adjust the size of the loupe using pinch gesture.

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When you use the Magnifier of Preview app on a PDF document, the loupe changes to a rectangular shape, with its size and position adapts to the document content such as paragraph boundary while you move or pinch to size.

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