Mac OS X: Unexpectedly Displays Negative Image (White on Black, Reverse Type)

Your computer may display a negative image if someone or something presses many keys at the same time. This is a feature of Universal Access that lets you toggle the display between negative and positive image by pressing the Control-Option-Command-8 key combination.
Symptom

Your see a negative image in the screen. Depending on system configuration, it may be black and white, such as that in Figure 1, or color negative, such as that in Figure 2.




Figure 1 Picture of black and white negative image display using Universal Access




Figure 2 Picture of color negative image display using Universal Access


Solution

You can toggle the display between positive and negative by using the Control-Option-Command-8 key combination. First, press and hold the modifier keys (Control, Option, Command). While holding the modifier keys, press 8.

The screen will go blank for a second and return in the opposite mode.
Published Date: Feb 20, 2012