Avoid using the virtual shutter button on the touch screen. It is nearly impossible to keep the camera from moving while depressing a button with no feel that is on the same plane as the lens and not in a natural position.
The mechanical button is perpendicular to the lens and can be "squeezed" between a finger and thumb bracing the bottom of the camera.
Also, a half push of the mechanical button will activate and lock the auto focus. A technique we will talk about later for stretching the focus range.
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