Casio EX-Z1 User Manual (en)

Quick Start Basics
If the image does not focus...
If the focus frame stays red and the back lamp is flashing green, it means that the 
image is not in focus (because the subject is too close, etc.) Re-point the camera at 
the subject and try to focus again.
If the subject is not in the center of the frame...
“Focus lock” (page 59) is the name of a technique you can use when you want to 
shoot an image in which the subject to be focused on is not within the focus frame in 
the center of the screen.