About AirPlay Mirroring in OS X Mountain Lion
Summary
Learn about AirPlay Mirroring in OS X Mountain Lion.
Products Affected
Apple TV (2nd generation), Apple TV (3rd generation), OS X Mountain Lion
AirPlay Mirroring lets you send what’s on your Mac screen to an HDTV wirelessly with Apple TV.

Requirements for AirPlay Mirroring in OS X Mountain Lion
An Apple TV
- Apple TV (2nd or 3rd generation) with software update v5.0 or later. See How to update Apple TV software.
Supported Macs
AirPlay Mirroring in OS X Mountain Lion takes advantage of the hardware video encoding capabilities of 2nd and 3rd Generation Intel Core processors. Hardware video encoding allows AirPlay Mirroring to efficiently deliver high frame rates while maintaining optimal system performance. The following Mac models have processors that support AirPlay Mirroring:
- iMac (Mid 2011 or newer)
- Mac mini (Mid 2011 or newer)
- MacBook Air (Mid 2011 or newer)
- MacBook Pro (Early 2011 or newer)
Which Mac do I have?
A network
AirPlay Mirroring requires either a Wi-Fi (802.11 a/g/n) connection or an Ethernet connection to the same local network that your Apple TV uses.
Turning AirPlay Mirroring on and off
If your Mac supports AirPlay Mirroring, an AirPlay Mirroring menu extra appears in the menu bar when an Apple TV is on the same network. Turn on mirroring by selecting an Apple TV from the AirPlay Mirroring menu:

Note: The AirPlay Mirroring menu extra icon is blue when AirPlay Mirroring is on (
).
You can also turn it on via System Preferences > Displays:

Note: If you don't see AirPlay Mirroring in Displays Preferences, then your Mac model does not support it.
To turn off AirPlay Mirroring, select "Turn Off AirPlay Mirroring" in the AirPlay Mirroring menu extra, or Off in Displays Preferences. You can also press the Menu button on the Apple TV remote to end the current AirPlay Mirroring session.
Optimizing image quality
Resolution Matching modes
You can choose between two desktop resolution matching modes that let you select which display will have the best image. When AirPlay Mirroring is turned on, select a "Match Desktop Size" choice via the AirPlay Mirroring menu extra.

- Match Desktop Size To: Apple TV
AirPlay Mirroring changes the desktop resolution to best match your Apple TV, resulting in a 16:9 image that fills the HDTV screen. This setting often produces the sharpest image on the HDTV. Note: The aspect ratio and/or resolution of the built-in Mac display may change to accommodate the Apple TV.
- Match Desktop Size To: This Mac
AirPlay Mirroring scales the contents of the desktop to fit on the Apple TV, leaving the resolution of your Mac's display unchanged. Use this setting for the sharpest image on your Mac's display. Note: Depending on your Mac model, the resulting image may not fill the HDTV screen.
Minimize video post-processing
HDTVs often apply picture quality enhancements intended to improve the look of film and video sources. In some cases, these enhancements can lead to over-sharpening artifacts when displaying the Mac desktop. Some HDTV models have built-in settings to change or disable the enhancements for use with computer (computer, presentation, or game modes). Otherwise, the controls for sharpness, detail enhancement and noise reduction can be used to optimize the appearance of the Mac desktop. Consult your HDTV’s manual for guidance on the appropriate settings for use with a computer.
Troubleshooting AirPlay Mirroring
Mac and Apple TV are on the same network, but no AirPlay Mirroring menu appears
Your Apple TV may be asleep. Simply press a button on your Apple TV remote to wake it up. After a few seconds, the AirPlay Mirroring menu extra will appear.
Make sure your Apple TV has the current software update installed.
Make sure you have the "Show mirroring options in the menu bar when available" checked.

The menu bar or Dock is cropped
Some HDTVs have bezels that cover a small percentage of the screen. This will result in a slight cropping of a full-resolution HDTV image. Depending on the HDTV model, AirPlay Mirroring may automatically adjust the picture size to prevent cropping. If you see cropping of the menu bar or dock on your HDTV when using AirPlay Mirroring, simply click the Overscan correction option in Displays preferences.

Additional Information
For more information about Apple TV and AirPort Mirroring, please see Apple TV: How to use AirPlay Mirroring.
For additional troubleshooting information, see Troubleshooting AirPlay and AirPlay Mirroring.
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