1. An image capturing apparatus comprising: an image capturing section; a pre-image acquiring section for acquiring a pre-image captured by the image capturing section when a focal point provided at a predetermined position within the image capturing region of the image capturing section is superimposed on a main subject; a focal distance adjusting section for adjusting a focal distance of the image capturing section to the main subject based on an analysis result of the pre-image acquired by the pre-image acquiring section; a captured image acquiring section for acquiring the image captured by the image capturing section when the image capturing section focuses on the main subject; a focal position storage section for storing a focal position on an image capturing range of the image capturing section; and an image storage section for storing a region image including the focal position stored in the focal position storage section in the pre-image acquired by the pre-image acquiring section in a nonvolatile memory in association with the captured image acquired by the captured image acquiring section.