Brother MFC-3200C - Manual (Page 180)

17 - 5 H O W T O S C A N U S I N G W I N D O W S ®
MFC3200C-US-FM6.0
When scanning photographs or other images for use in a word processor or other
graphics application, you should try different settings for the contrast, mode and
resolution to see which settings best suit your needs.
Custom:
If you selected Custom as the size, type the Width and Length .
Or, you can check the Business Card Size box to adjust the scanning area to
business card or a custom size automatically.