Canon POWERSHOT S100 User Manual page 102

You can use manual focus when auto focus is not possible. If you press the
shutter button halfway after roughly focusing manually, you can fine tune the
focus.
MF Indicator
Choose _.
After pressing the _ button, press the _
buttons or turn the • dial to choose _,
then press the @ button.
_]_ and the MF indicator appear.
..... Focusing roughly.
The side bar shows your focal point and a
distance display for the M F indicator. While
looking at the magnified area, turn the
dial to find an approximate focus.
Fine tuning the focus.
If you press the shutter button halfway, you
can fine tune the focus (Safety MF).
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