Image capturing apparatus, control method of controlling the same, and storage medium

A method of controlling an image capturing apparatus including a focus detection unit configured to perform focus detection based on a phase difference between a plurality of image signals obtained by photo-electrically converting light beams that have respectively pass through different partial pupil regions of an imaging optical system, and an image blur correction unit configured to correct image blur of an object image by driving an optical member for image blur correction, the method comprising:

• determining reliability of a focus detection result detected by the focus detection unit based on information regarding drive history of the image blur correction unit, information regarding a focus detection area on which the focus detection unit performs focus detection, and information regarding vignetting that occurs in light beams that pass through the imaging optical system, in a period during which the focus detection unit performs focus detection.