ViewSonic M1 User Manual page 40

Menu
Keystone
Description
Adjust trapezoidal screen image distortion.
Manual
Keystone can be adjusted manually from -40 to 40.
Auto V Keystone
Provides a rectangular screen image by automatically
adjusting the keystone number when there is a
trapezoidal screen image caused by the tilting of the
projector.
• Enable: Automatically adjust the keystone number.
• Disable: Manually adjust the keystone number.
NOTE: If Manual is selected, Auto V Keystone will
change to Disable automatically.
40