Force the viewport to be square.
Allow the viewport to conform to the aspect ratio of the data.
The fullframe command sets the value of the fullframe parameter to either "on" or "off". A value of "on" forces the output viewport to be square, thereby allowing the aspect ratio of the data to be other than 1:1. A value of "off" is the default, and this causes the data aspect ratio to be 1:1. This command is useful when the image being examined is long and narrow, and the viewport is too narrow to see sufficient detail.