Canon PIXMA iP6600D Series Quick Start Manual page 21

Basic Printing
(5) Select 4 x 6 in 101.6 x 152.4 mm or 5 x 7 in 127.0 x 177.8 mm from Page Size in
the printer driver.
For a detailed description of the printer driver settings, see "Printing with
Windows" on page 20, or "Printing with Macintosh" on page 24.
~Important
Always load paper in portrait orientation. loading paper in
landscape orientation can cause the paper to be jammed.
Portrait landscape
WHote
We recommend using genuine Canon photo media when printing
photographs.
See "Using Specialty Media" on page 18.
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