Canon EOS REBEL T8i Advanced User's Manual page 110

FAQ
Focusing is not possible (indicated by a blinking < > in the viewfinder, in
viewfinder shooting, or by an orange AF point in Live View shooting).
Aim the AF point over an area with good contrast, then press the shutter button halfway
( ). If you are too close to the subject, move away and shoot again.
Multiple AF points are displayed simultaneously.
Focus has been achieved at all those points.
Pressing the shutter button halfway does not focus on the subject.
If the focus mode switch on the lens is set to < >, set it to < >.
The shutter speed display is blinking.
Since it is too dark, taking the picture may result in a blurred subject due to camera
shake. Using a tripod, the built-in flash, or an external flash ( ) is recommended.
Pictures are too dark.
Raise the built-in flash in advance to enable automatic flash firing, in case subjects in
daytime shots are backlit, or when shooting under low light.
The built-in flash fired repeatedly when raised while shooting under low light.
To make autofocusing easier, the built-in flash may fire repeatedly when you press the
shutter button halfway ( ).
Pictures taken with flash are too bright.
Pictures may be bright (overexposed) if you shoot subjects at close range in flash
photography. Move away from the subject and shoot again.
The bottom part of pictures taken with flash 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. If you are using a lens hood, try
removing it before shooting.
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