Imaging apparatus and image blur correction method

An imaging apparatus comprising:

• an acceleration detection unit that detects accelerations of the imaging apparatus in directions of three orthogonal axes;
• a reference vector generation unit that, in a case in which a difference between a magnitude of a resultant vector of the accelerations in the directions of the three orthogonal axes detected by the acceleration detection unit and a magnitude of acceleration of gravity is equal to or less than a predetermined threshold value, generates a reference vector using the resultant vector;
• a shake correction unit that corrects an image blur caused by translational shakes in directions of two orthogonal axes perpendicular to at least an optical axis of an imaging optical system, using the reference vector, based on the accelerations in the directions of the three orthogonal axes detected by the acceleration detection unit;
• a gravitational acceleration estimation unit that estimates acceleration of gravity in a coordinate system including the three orthogonal axes which is rotated in operative association with a change in posture of the imaging apparatus;
• and
• a gravitational acceleration correction unit that corrects the acceleration of gravity estimated by the gravitational acceleration estimation unit based on the reference vector,
• wherein the shake correction unit corrects the image blur caused by the translational shakes in the directions of the two orthogonal axes perpendicular to at least the optical axis of the imaging optical system, based on accelerations obtained by subtracting corresponding axial-direction components of the acceleration of gravity corrected by the gravitational acceleration correction unit from the accelerations in the directions of the three orthogonal axes detected by the acceleration detection unit.