Apple's pinch-zoom option for changing icon sizes in the Finder was disabled in Lion, but there are some options for quickly adjusting icon sizes.
Topher KesslerMacFixIt Editor
Topher, an avid Mac user for the past 15 years, has been a contributing author to MacFixIt since the spring of 2008. One of his passions is troubleshooting Mac problems and making the best use of Macs and Apple hardware at home and in the workplace.
In OS X 10.6 Snow Leopard, Apple introduced an option to control icon sizes by simply using the pinch-zoom gesture on Macs with multi-touch trackpads. If you pulled your fingers together then the icon sizes in the current window would get smaller, and if you spread your fingers then the icons would get larger.
This feature has been removed in OS X Lion, which has frustrated a number of people who have come to rely on its convenience. While the Finder's preferences file may have an option called "EnableZoomPinch" for some users, this option is likely just left over from the previous Finder version in OS X 10.6, since altering its setting from "false" to "true" has no effect on the Finder in Lion.
Apple has a slider at the bottom of each Finder window that appears when in icon view.Screenshot by Topher Kessler
Unfortunately it seems the option to pinch zoom has been fully removed from the Finder. While Apple could have altered it to require a modifier key or some other alternative approach if the default behavior was a burden to most people, Apple instead chose to disable it altogether.
Currently if you are interested in managing icon sizes in the Finder, there are only two options available to you in OS X Lion:
The status bar
Apple has placed a small slider at the bottom of every Finder window, which allows you to adjust the icon sizes for that window.
The view options in the Finder allow any window's icons to be resized, including the DesktopScreenshot by Topher Kessler
This option is perhaps the next most convenient option than the use of pinch zoom; however, it will only work for Finder windows and therefore will not affect the icon sizes of the Desktop.
The view options
The second place where you can adjust icon sizes is in the Finder's "View Options" panel, which will adjust various window properties including icon size and labeling options.
To get to the view options for a window, click it to ensure it is the active window, and then press Command-J or choose "Show View Options" from the "View" menu. In here you can then use the slider to change the icon sizes.
Unlike the Finder window slider, the View Options panel will work for the desktop.
