Canon EOS 90D Instruction Manual page 291

 Pictures are too dark.
Raise the built-in fl ash to enable automatic fl ash fi ring, in case subjects in
daytime shots are backlit, or when shooting under low light.
The built-in fl ash fi red repeatedly when raised while

shooting under low light.
To make autofocusing easier, the built-in fl ash may fi re repeatedly when
you press the shutter button halfway ( = 126).
Pictures taken with fl ash are too bright.

Pictures may be bright (overexposed) if you shoot subjects at close range
in fl ash photography. Move away from the subject and shoot again.
The bottom part of pictures taken with fl ash is unnaturally

dark.
Shooting subjects that are too close may make the shadow of the lens
visible in your shots. Move away from the subject and shoot again. Also
remove the lens hood before shooting.
Note the following if you are not using the built-in fl ash.
Under low light where camera shake tends to occur, the viewfi nder's shutter
o
speed display will blink. Hold the camera steady or use a tripod. When using
a zoom lens, you can reduce the blur caused by camera shake by setting the
lens to the wide-angle end.
When shooting portraits under low light, tell subjects to stay still until you have
o
fi nished shooting. Any movement as you shoot will make the person look
blurry in the picture.
Fully Automatic Shooting (Scene Intelligent Auto)
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