F11 displays the left image.
Shift+F11 displays the right image.
This function is useful if you want to Save or Print a single image or view a large number of JPS files (for example) as a 2D image.
Ctrl+F11 alternates between the left and right images at a rate determined by the user.
The above box will be displayed to allow you to set the flashing rate.
This mode is mainly intended to help the creation of Animated GIF's.