Either of these keys centers the model and adjusts its size to fit the screen, without rotating. This is a very handy feature. Whenever the view becomes awkward, just press either of these keys to give a convenient view of the model. Because Deep View displays only in wireframe, without depth cueing, stereo viewing will help you to carry out mouse functions precisely. Here's some instruction in Stereo Viewing .
Press help to adjust size and centering.
You may need to adjust stereo settings further in order to achieve comfortable viewing. Stereo Display Set stereo view rotation and separation. Decrease the separation if the views are too far apart to fit the window. For any functions that require clicking on an atom while viewing in stereo, you must click on the atom in the left image. The right image does not respond to mouse clicks.