Patent ID: 8736745

Claim:
A camera in which a lens unit is detachable, the lens unit including an image pickup lens configured to form an object image, the lens unit compatible with a first focus detection unit configured to provide a focus detection by detecting a phase difference between a pair of object images formed by utilizing a first pupil splitting unit, the camera comprising: a second focus detection unit configured to provide a focus detection by detecting a phase difference between a pair of object images formed by utilizing a second pupil splitting unit different from the first pupil splitting unit; a third focus detection unit configured to provide a focus detection by detecting a peak position of a contrast of the object image by performing scanning that changes a distance between an image pickup device and a focus position formed by the image pickup lens; and an acquisition unit configured to acquire correction information used to correct a shift amount between a focus detecting light flux and an image-pickup light flux from the image pickup lens, wherein the third focus detection unit performs the scanning in a single direction from a focus position detected by the second focus detection unit, the single direction being set based on the correction information.