Epson Perfection V500 - Manual (Page 106)

You can move the marquee, adjust its size, and create multiple marquees on one image (normal
preview only) to scan different image areas in separate scan files. Follow these steps.
Note for Home Mode users:
When you use the Thumbnail preview with film or slides, Epson Scan automatically
creates marquees around your image(s) for you. If you need to adjust a marquee,
click inside it and click the delete marquee icon before completing the steps in
this section. If you do not need to adjust any marquees, skip to Adjusting the
Color and Other Image Settings .