Canon MultiPASS F20 Software User's Manual page 66

Multi Crop (Scanning two or more photos at one time):
If you use Multi Crop (Advanced Mode), you can specify detailed
settings for scanning of two or more photos (small documents) at one time.
In the same way as Multi-Photo Scan, photos that have an overall
whitish appearance or have a whitish border may not be cropped
accurately. Also, documents other than photos (particularly documents
printed on white paper, hand-written text, business cards etc.) may also
not be cropped accurately.
Automatically there is a correction of documents that are not straight.
However this will not happen is the image is off by more than 10 degrees.
Unlike Multi Crop, Color Mode and Resolution can be set freely.
1. If using the Toolbar to scan, click Settings on the Toolbar. On the
Toolbar Settings tab, click Show scanner driver before scanning, select
it and click OK.
2. Place the photos on the platen glass.
Please leave a gap of at least 0.4 inches (1 cm) between each photo
and the edge of the Platen glass. You should be able to place up to 10
photos on the platen glass at any one time if desired.
Chapter 4 Scanning 62