Canon PowerShot SD4500 IS Digital ELPH User Manual page 57

You can use the digital zoom to zoom up to approximately 40x and capture
subjects that are too far away for the optical zoom to enlarge. The images
may appear coarse, however, depending on the recording pixel setting (p. 74)
and the zoom factor used.
Zoom Factor
Move the zoom lever toward E_3.
Hold the lever until zooming stops.
The zoom wil! stop when the largest
possible zoom factor without image
deterioration has been reached, and the
zoom factor will appear when you release
the zoom lever.
Move it toward [_q again.
The digital zoom will zoom in even further
on the subject.
Images shot at zoom factors that appear in blue wilI be coarse.
To turn off the digital zoom, press the MENU button to choose [Digital Zoom] in
the _ tab, then choose [Off].
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