Canon EOS 5D MARK II Instruction Manual page 81

:E_ Automatic Sensor Cleaning
Whenever you set the power switch to <ON/,.J> or <OFF>, the Self
Cleaning Sensor Unit operates to automatically shake 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
1 Select [Sensor cleaning].
_ Under the [_:] tab, select [Sensor
cleaning], then press <__>.
[]
Select [Clean now ,*E_ ].
_ Turn the <O> dial to select [Clean
now :E3+ ], then press < __ >.
® Select [OK], then press <__>.
_t_, T he 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 camera bottom is
placed on a table or other flat surface.
Even if you repeat the sensor cleaning, the result will not improve that
much Right after the sensor cleaning is finished, the [Clean now_l::3,]
option will remain disabled temporarily.
Disabling Automatic Sensor Cleaning
® in step 2, select [Auto cleaning :E3_] and set it to [Disable].
_, The sensor cleaning will no longer be executed when you set the
power switch to <ON/M> or <OFF>.
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