A non-transitory computer-readable storage medium storing a program for causing a computer to execute a method for an image pickup apparatus that comprises a pickup device including pixels that photoelectrically converts incident light from a subject that has passed through different regions of an exit pupil of an image pickup optical system to generate a plurality of pickup signals,
- the method comprising:
- setting a focus adjustment region used in focus adjustment of the image pickup optical system in a live view image displayed on a display device;
- making a determination whether or not the focus adjustment in the focus adjustment region set in the live view image is possible;
- and
- differentiating a display of the focus adjustment region on the display device, according to a result of the determination.