How to: Blacken or unblacken the screen during a slide show.
Solution:
Use the 'Show Popup' menu or press the B key.
1) To blacken the screen:
a) Right-click on the screen while the slide show is on. (The Show shortcut menu appears.)
Show shortcut menu
b) Select 'Screen' from the menu. (A submenu appears.)
c) Select 'Black Screen'. (The screen turns black.)
2) To unblacken the screen:
a) Right-click on the screen while the slide show is on. (The Show shortcut menu appears.)
Show shortcut menu
b) Select 'Screen' from the menu. (A submenu appears.)
c) Select 'Unblack Screen'. (The screen returns to normal.)
NOTE 1: The B key can also be pressed to alternate between blackening and unblackening.
NOTE 2: Blackening the screen automatically erases any annotations.