How to rotate a display on OS X
From ArticleWorld
Although the feature is largely unknown, Apple's OS X offers the possibility of rotating the display image. This has long been known by digital artists, who find it very useful when working with portrait-format images. Apple systems equipped with ATI cards can rotate the display; however, nVidia-based ones cannot do this. The reason why Apple has taken this decision is not known yet, taking into account that nVidia cards can rotate images on Windows.
Procedure
- Connect the monitor on which you want to rotate the image to the computer
- Go to System Preferences, Displays
- Go to Rotate and select the appropriate rotation options for your display.
Notes
Do note that, on some displays, it was reported that the font smoothing does not work correctly, resulting in a rather sluggish-looking text. You should also make sure that you are rotating a monitor which supports the feature and the final resolution to which you rotate. Normally, nothing bad can happen if the rotation is not supported, as the image will appear visibly distorted and unusable. You should simply turn off the monitor and disable the rotation. However, on some rare occasions, rotation may damage the monitor. Therefore, if you are not sure that the monitor supports rotation, and for some reason damaging it would be irreparable, you should not experiment.ยง