Canon EOS REBEL T8i Advanced User's Manual page 664

Cleaning Automatically
1.
Select [Auto cleaning
2.
Select a setting item.
Use the <
Note
For best results, clean with the camera in a stable position on a desk or other flat
surface.
Even if you repeat the sensor cleaning, the result will not improve much. Note that
[Clean now ] may not be available immediately after cleaning.
Dots of light may appear in captured images or on the shooting screen if the sensor
is affected by cosmic rays or similar factors. By selecting [Clean now
appearance may be suppressed (
].
> < > keys to select an item, then press <
).
664
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