Canon EOS Rebel XS Instruction Manual page 33

Automatic Sensor CJeaning _yysJ/_zy_d
Whenever you set the power switch to <ON> or <OFF>, the Self
Cleaning Sensor Unit operates to _utomatically share off the dust on
the front of the sensor Normally, you need not be aware of this
operation. However, you can execute the sensor cleaning at anytime as
well as disable it.
Cleaning the Sensor Now
Select [Sensor cleaning].
Under the [_P] tab, select [Sensor
cleaning], then press <8>
% Select [Clean now _- ].
_, Select [Clean now_!_], then press
_ Select [OK], then press <_>.
_,>The screen will indicate that the
sensor is being cleaned. Although
there will be a shutter sound, a
picture is not taken.
[_ For best results, do the sensor cleaning while the c_mera bottom S
pieced on a table or other surface at a perpendicular angle.
Even _fyou repeat the sensor cleaning, the result will not imfirove that
much. Right after the sensor cleaning iS finished, the [Clean i_ow*[:3,]
option will rems!r_d!ssbled terr_f!otar!ly.
Disabling Automatic Seasor Cleaning
® In step 2, select [Auto cleaning _![u ] and set it to [Disable]
#> The sensor cleaning will no longer be executed when you set the
power switch to <ON> or <0FF>
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