SatView's default area for plotting is the entire globe (though this may be changed via the .xresources file). In many cases, you will be interested in viewing only a small subsection of the globe. This can be accomplished interactively by zooming in to the region of interest. This operation is performed in two steps:
(1) Indicate the area of interest.
(2) Select the Zoom button from the control area.
You indicate your area of interest with the mouse by pressing and holding the left mouse button at the upper left corner of the desired section, and dragging the cursor to the lower right corner and releasing the button. As you are dragging the mouse, a rubberbanded box will appear to show you the exact boundaries. The area you select must always be square. This restriction is necessary to preserve the aspect ratio of the image. After delineating this square region, select the Zoom button (or pick Zoom In to Bounding Box from the Zoom menu), and the image area will be erased and a new image drawn.