Canon Leather Soft Case 70 Advanced User's Manual page 49

The following occurs when [Face Detect] is selected.
- The camera displays up to three frames where it has
detected a face. At this point, the frame the camera
judges to be the main subject appears in white while the
others appear in gray. Pressing the shutter button
halfway displays up to 9 green AF frames.
- If no white frame displays and all the frames appear in
gray, images will be shot using the [On] option rather
than [Face Detect].
- The camera may mistakenly identify non-human subjects
as a face. If this occurs, switch to the [On] or [Off] option.
- In certain cases, faces may not be detected.
Examples:
• Faces near the screen edges or faces that appear
extremely small, large, dark or bright in relation to the
overall image.
• Faces turned to the side or at a diagonal, or faces with
a portion hidden.
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