4.3Scanning
Preview: Previews the image to be scanned, allowing you to adjust to scan area prior to final scan.
Scan:Executes the final Scan.
Exit:Cancels the current scan job.
Document Size: To designate the size of your document, just click on its icon on the margin of the preview window
As shown in the figure below, in the Preview window, you can define the area to be scanned by dragging the four cursor auxiliary lines.